Memoire Online - Prevalence and associated factors of hypertension in primary school children in mbankomo subdivision in the mefou and akono division, centre region

The measure of blood pressure is not carried out systematically during pediatric consultations. This leads to discovery of hypertension only whensigns of severity occur. Studies in many parts of the world, have demonstrated a higher blood pressure prevalence in urban zones[27].

In Cameroon, most studies on HTN in children were carried out in urban and semi-urban settings -''''''''''''''''''''''''''''''''''''''''''''''''''''''`'''''''''''''[24-26]. The prevalence varied between 2.2% in Yaounde'''''''''''''''''''''''`'''''''''''''[25], 2.9% in Bertoua'''''''''''''''''''''''''''''''[24] and 3.2% in Buea[26].Lifestyle in urban and rural settings are different, and knowing its influence on HTN, we decided to carry out this study in a rural setting. The Mbankomo subdivision found in the Centre region was thereby chosen, because of its easy access and the abundance of schoolsit has.

From our results, we will draw conclusions and recommendations to help raise awareness of pediatric HTN; promote screening as well as ensure early management and foster educational programs on healthy lifestyle from childhood. This will go a long way to achieve the sustainable development goal(SDG) 3.4--[28], which aims by the year 2030,at reducing by one third premature mortality from non-communicable diseases through prevention and treatment and promote mental health and well-being by the year 2030.

CHAPTER III: RESEARCH QUESTION

What is the prevalence and associated factors of hypertension in primary school children in Mbankomo subdivision found in theMefou and Akono division, Centre Region?

CHAPTER IV: RESEARCH HYPOTHESIS

Hypertension exists in primary school children of Mbankomo subdivision, with associated factors.

CHAPTER V: OBJECTIVES

· Determine the prevalence and associated factors of hypertension in children attending primary schools in Mbankomo subdivision found in theMefou and Akono division, Centre Region.

· Assess the socio-demographic characteristics of primary school children in the Mbankomo subdivision.

· Determine the prevalence of elevated BP and hypertension among primary school children in Mbankomo subdivision.

· Childhood: This is the period of life between infancy and onset of puberty and is usually between 2 and 10 years inclusive[29].

· Adolescence: This is the transition period of life between childhood and adulthood and is between 11 and 19years of age[30].

· Childhood hypertension: It refers to BP equal to or over the age- and gender-specific 95^th percentile value[19].

· Prehypertension: It is considered as BP equal or greater than 90^th percentile and less than 95^th percentile for age, height, and gender or BP equal or more than 120/80mmHg[19].

· Body mass index (BMI): It is a simple index of weight and height that is commonly used to classify overweight and obesity in adults. It is the weight in kilograms divided by the square of the height in meters[31].

· Childhood obesity: Children with BMI equal or greater than the age-gender-specific 95^th percentile of growth chart[31].

· Childhood overweight: BMI equal or greater than 85^th percentile but less than the age-gender specific 95^th percentile of growth chart[31].

· Normal weight: BMI equal or greater than 5^th percentile but less than the age-gender specific 85^thpercentile of growth chart[31].

· Underweight: BMI less than the age-gender specific 5^thpercentile of the growth chart[31].

In terms of non-communicable diseases in children, HTN comes second following Asthma and Obesity[32]. The true incidence of hypertension in paediatric population is unknown[33]. The prevalence is increasing in accordance with widespread life-style changes and epidemic of childhood obesity[23]. Alarming data exist on the prevalence of childhood HTN not only in industrialized countries, but also in developing countries'-[6,34]. Because of differences in genetic and environmental factors, incidences vary from country to country and even from region to region in the same country[33,35]. The prevalence of HTN among children reported by various studies ranges from 5.4% to 19.4%[5,36]. The prevalence appears to be increasing and is estimated to be 1% to 4% in Europe and 4% to 14% in the USA[35,37]. In Sub-Saharan Africa: 4.9% in Sudan [5]; 11.4% in South Africa[38]; 10% in Congo'-[6]; 4.7% in Port Harcourt, Nigeria[23]. In Cameroon: 2.2% in Yaoundé '''''''''''''''''''''''`'''''''''''''[25], 2.9% in Bertoua'''''''''''''''''''''''''''''''[24]and 3.2% in Buea[26].

BP in children varies with age, gender, and height. However, these relations do not become evident until children reach school age (3 years) [33,39]. Numerous investigators have noted a correlation between BP of parents and their offspring[40]. Familial aggregation of BP is detectable early in life. Some data relate this association to concomitant obesity in both parents and child[8].

Moreover, studies have shown that there are no significant differences in BP between girls and boys younger than 6 years. From that age until puberty, BP is slightly higher in girls than in boys. At puberty and beyond, BP is slightly higher in male adolescents than in comparable aged femaleadolescents[35,39,41,42].

There are no differences in BP between African American and white children[8,41].

According to the French consensus, normal BP in children is defined as SBP and DBP less than 97.5^th percentile for age, sex and height[43]; Paediatric HTN defined as SBP and/or DBP equal or more than 97.5^th percentile for age, sex and height taken on at least 3 separate occasions[19,43]. This school of thought further classified Pediatric HTN into 3 stages as follows:

Source:Andre J. Hypertension artérielle chez l'enfant et l'adolescent. EMC - Cardiol-Angéiologie. 2005 Nov;2(4):478-90.

According to the AAP(American Academy of Pediatrics) in 2017[44] which revised the Fourth Report on Blood Pressure Control in Children of NHBPEP[19], the normal BP in children is defined as BP less than 90^thpercentile for age, sex and height. Paediatric HTN is defined as BP of 95^th percentile or more, measured on at least three separate occasions using the auscultatory method[44]. This school classifies paediatric HTN into 4 classes as follows:

Source:-Flynn JT, Kaelber DC, Baker-Smith CM, et al. Clinical Practice Guideline for Screening and Management of High Blood Pressure in Children and Adolescents. Pediatrics. 2017;140(3):e20171904..

Presented below are charts showing the approximation of blood pressure centiles from the task force report on BP control in children''[45] :

Source: Ashish B, Cynthia B, Monesha GM, Joshua S. Blood pressure percentile charts to identify high or low blood pressure in children. BMC Pediatrics. (2016);16:98.

VI.1.3.1HISTORY OF THE PRESENT DEFINITION AND CLASSIFICATION OF PEDIATRIC HYPERTENSION

In 1977, the first Report of the Task Force on Blood Pressure Control in Children was published in the United States [46], with the aim of standardizing measuring and monitoring methods; standardizing distribution curves of arterial BP in healthy children; and of organizing BP into percentile graphs according age and sex[46]. In this study, the 95^thpercentile was established as normotensive levels and the recommendation that «All children 3 years of age or older should have their BP measured during any health maintenance visits or emergency visits». Since then, series of nationwide and international studies have been undertaken and new concepts elaborated.

In 1987, the 2^nd Report of the Task Force on BP Control in Children was released which established that «Normal BP is less 90^thpercentile for age, sex and height: and HTN greater than 95^thpercentile» and this report also recommended «5^th phase korotkoff sound as reference for DBP[19].

The Third Report of the Task Force, published in 1996, provided further details regarding the diagnosis and treatment of HTN in infants and children.

In 2004, the Fourth Report later introduced, prehypertension, Stage 1 HTN and Stage 2 HTN. This classification was created to align the categories for children with the categories for adults from the recommendations of the Seventh Report of the Joint National Committee on Prevention, Detection, Evaluation, and Treatment of Hypertension[19].

In 2017, the AAP updated the 2004 «Fourth Report on the Diagnosis, Evaluation, and Treatment of High Blood Pressure in Children and Adolescents» by making the following major changes; the replacement of the term `prehypertension' with the term `elevated blood pressure', new normative pediatric blood pressure (BP) tables based on normal-weight children, a simplified screening table for identifying BPs needing further evaluation, a simplified BP classification in adolescents =13 years of age that aligns with the forthcoming American Heart Association and American College of Cardiology adult BP guidelines, a more limited recommendation to perform screening BP measurements only at preventive care visits, streamlined recommendations on the initial evaluation and management of abnormal BPs, an expanded role for ambulatory BP monitoring in the diagnosis and management of pediatric hypertension, and revised recommendations on when to performechocardiography in the evaluation of newly diagnosed hypertensivepediatric patients (generally only before medication initiation), along with a revised definition of left ventricular hypertrophy[44].

Secondary HTN is defined as HTN which occurs as a result of an underlying disorder. When no identifiable cause is found, it is referred to as Primary or Essential HTN.

Essential hypertension is mostly found in adults as compared to that found in children and adolescents''[2,19,47]. Significant determinants for essential hypertension include family history of hypertension, cardiovascular disease, and obesity as well as low birth weight, insulin resistance, sedentarity, salt consumption and tobacco intake'[13,19]. Some sleep disorders like: Obstructive sleep apnea, insomnia, and restless legs syndrome have been reported to be associated with essential hypertension [15,48].

Secondary hypertension which the most common form, is more common in children than in adults''[2,19,35]. It can be present in adolescents, especially if they have physical findings not typically seen with essential hypertension.67% to 80% of secondary HTN are of renal origin with 34.89% being nephrotic syndrome'''''''''''''''''''''''''''''''[24]. Other causes include endocrine disease (e.g pheochromocytoma, hyperthyroidism) and pharmaceuticals (e.g., oral contraceptives, sympathomimetics, some over-the counter medications, dietary supplements). Transient rise in blood pressure, which can be mistaken for hypertension, is seen with caffeine use and certain psychological disorders (anxiety and stress)[49,50].The causes of secondary HTN can be seen on the following table:

Sources:- National High Blood Pressure Education Program Working Group on High Blood Pressure in Children and Adolescents. The fourth report on the diagnosis, evaluation, and treatment of high blood pressure in children and adolescents. Pediatrics. 2004 Aug; 114(2 Suppl 4th Report):555-76.

Hypertension is a multifactorial disease, influenced by genetic, racial, geographic, cultural and dietary pattern[8]. Identifying and modifying the risk factors, reduces the incidence and complications in adults[16].Studies have noted a strong association between overweight, obesity and high BP. In particular, obesity epidemic appears to be the major contributor of the increasing trends in childhood HTN[16,35,41,49].

However, apart from obesity, other factors such as: dietaryhabits, lack of physical activity, sedentary behaviour, as well as increase dietary salt intake have been associated with increased BP in children independent of body composition. These include[8]:

Blood Pressure(BP) is determined by a balance between cardiac output and vascular resistance.

A rise in either of these variables, in the absence of a compensatory decrease in the other, increases mean BP, which is the driving pressure[52]. The total peripheral resistance reflects the vasomotor tone generated by the arteries (mostly those of small calibre) and volemia to a lower extent[52,53].Contraction of smooth muscle cells is thought to be related to a rise in intracellular calcium concentration, which may explain the vasodilatory effect of drugs that block the calcium channels. Prolonged smooth muscle constriction is thought to induce structural changes with thickening of the arteriolar vessel walls possibly mediated by angiotensin, leading to an irreversible rise in peripheral resistance[53].The cardiac output is the product of heart rate(HR) and stroke volume(SV):

The stroke volume depends on the quantity of blood present in the left ventricle at the end of diastole and the heart rate depends on the equilibrium between the sympathetic and the parasympathetic systems[52].

It has been postulated that in very early hypertension the peripheral resistance is not raised and the elevation of the blood pressure is caused by a raised cardiac output, which is related to sympathetic over-activity. The subsequent rise in peripheral arteriolar resistance might therefore develop in a compensatory manner to prevent the raised pressure being transmitted to the capillary bed where it would substantially affect cell homeostasis[53].

Source: Beevers G, Lip GYH, O'Brien E. The pathophysiology of hypertension. BMJ. 2001 Apr 14;322(7291):912-6.

The reninangiotensin system may be the most important of the endocrine systems that affect the control of blood pressure. Renin is secreted from the juxtaglomerular apparatus of the kidney in response to glomerular under perfusion or a reduced salt intake. It is also released in response to stimulation from the sympathetic nervous system[53].

Renin is responsible for converting renin substrate (angiotensinogen) to angiotensin I, a physiologically inactive substance which is rapidly converted to angiotensin II in the lungs by angiotensin converting enzyme (ACE). Angiotensin II is a potent vasoconstrictor and thus causes a rise in blood pressure. In addition it stimulates the release of aldosterone from the zona glomerulosa of the adrenal gland, which results in a further rise in blood pressure related to sodium and water retention[53].

The circulating reninangiotensin system is not thought to be directly responsible for the rise in blood pressure in essential hypertension. In particular, many hypertensive patients have low levels of renin and angiotensin II (especially elderly and black people), and drugs that block the reninangiotensin system are not particularly effective[53].

There is, however, increasing evidence that there are important noncirculating «local» reninangiotensin epicrine or paracrine systems, which also control blood pressure.

Local renin systems have been reported in the kidney, the heart, and the arterial tree. They may have important roles in regulating regional blood flow[53].

Figure 4: Reninangiotensin system and effects on blood pressure and aldosterone release[53]

Source: Beevers G, Lip GYH, O'Brien E. The pathophysiology of hypertension. BMJ. 2001 Apr 14;322(7291):912-6.

Sympathetic nervous system stimulation can cause both arteriolar constriction and arteriolar dilatation. Thus the autonomic nervous system has an important role in maintaining a normal blood pressure. It is also important in the mediation of short term changes in blood pressure in response to stress and physical exercise.

There is, however, little evidence to suggest that epinephrine(adrenaline) and norepinephrine (noradrenaline) have any clearrole in the aetiology of hypertension.Nevertheless, their effects are important, not least because drugs that block the sympathetic nervous system do lower blood pressure and have a well-establishedtherapeutic role[53].

It is probable that hypertension is related to an interaction between the autonomic nervous system and the reninangiotensin system, together with other factors, including sodium, circulating volume, and some of the more recently described hormones[53].

Figure 5: The autonomic nervous system and its control of blood pressure[53]

Source: Beevers G, Lip GYH, O'Brien E. The pathophysiology of hypertension. BMJ. 2001 Apr 14;322(7291):912-6.

Vascular endothelial cells play a key role in cardiovascular regulation by producing a number of potent local vasoactive agents, including the vasodilator molecule nitric oxide and the vasoconstrictor peptide endothelin. Dysfunction of the endothelium has been implicated in human essential hypertension[53].

Modulation of endothelial function is an attractive therapeutic option in attempting to minimise some of the important complications of hypertension. Clinically effective antihypertensive therapy appears to restore impaired production of nitric oxide, but does not seem to restore the impaired endothelium dependent vascular relaxation or vascular response to endothelial agonists. This indicates that such endothelial dysfunction is primary and becomes irreversible once the hypertensive process has become established[53].

Many other vasoactive systems and mechanisms affecting sodium transport and vascular tone are involved in the maintenance of a normal blood pressure. It is not clear, however, what part these play in the development of essential hypertension. Bradykinin is a potent vasodilator that is inactivated by angiotensin converting enzyme. Consequently, the ACE inhibitors may exert some of their effect by blocking bradykinin inactivation[53].

Endothelin is a recently discovered, powerful, vascular, endothelial vasoconstrictor, which may produce a salt sensitiverise in blood pressure. It also activates local reninangiotensin systems. Endothelial derived relaxant factor, now known to be nitric oxide, is produced by arterial and venous endothelium and diffuses through the vessel wall into the smooth muscle causing vasodilatation.

Atrial natriuretic peptide is a hormone secreted from the atria of the heart in response to increased blood volume. Its effect is to increase sodium and water excretion from the kidney as a sort of natural diuretic. A defect in this system may cause fluid retention and hypertension[53].

Sodium transport across vascular smooth muscle cell walls is also thought to influence blood pressure via its interrelation with calcium transport. Ouabain may be a naturally occurring steroidlike substance which is thought to interfere with cell sodium and calcium transport, giving rise to vasoconstriction.

Source: Beevers G, Lip GYH, O'Brien E. The pathophysiology of hypertension. BMJ. 2001 Apr 14;322(7291):912-6.

Patients with hypertension demonstrate abnormalities of vessel wall (endothelial dysfunction or damage), the blood constituents (abnormal levels of haemostatic factors, platelet activation, and fibrinolysis), and blood flow (rheology, viscosity, and flow reserve), suggesting that hypertension confers a prothrombotic or hypercoagulable state. These components appear to be related to target organ damage and long term prognosis, and some may be altered by antihypertensive treatment[53].

Source: Beevers G, Lip GYH, O'Brien E. The pathophysiology of hypertension. BMJ. 2001 Apr 14;322(7291):912-6.

Epidemiologically there is a clustering of several risk factors, including obesity, hypertension, glucose intolerance, diabetes mellitus, and hyperlipidaemia. In obese children, hyperinsulinemia may elevate BP by increasing sodium reabsorption and sympathetic tone. The complexity of the system explains the difficulties often encountered in identifying the mechanism that accounts for HTN. These difficulties are the main reasons why treatment is often designed to affect regulatory factors rather than the cause of the disease[48,50].

Indeed some hypertensive patients who are not obese display resistance to insulin. There are many objections to this hypothesis, but it may explain why the hazards of cardiovascular risk are synergistic or multiplicative rather than just additive.Although separate genes and genetic factors have been linked to the development of essential hypertension, multiple genes are most likely contribute to the development of the disorder in a particular individual. It is therefore extremely difficult to determine accurately the relative contributions of each of these genes.

Nevertheless, hypertension is about twice as common in subjects who have one or two hypertensive parents, and many epidemiological studies suggest that genetic factors account for approximately 30% of the variation in blood pressure in various populations. This figure can be derived from comparisons of parents with their monozygotic and dizygotic twin children, as well as their other children, and with adopted children. Some familial concordance is, however, due to shared lifestyle (chiefly dietary) factors[53].

Some specific genetic mutations can rarely cause hypertension. Experimental models of genetic hypertension have shown that the inherited tendency to hypertension resides primarily in the kidney. For example, animal and human studies show that a transplanted kidney from a hypertensive donor raises the blood pressure and increases the need for antihypertensive drugs in recipients coming from «normotensive» families. Conversely a kidney from a normotensive donor does not raise the blood pressure in the recipient.

Increased plasma levels of angiotensinogen, the protein substrate acted on by renin to generate angiotensin I, have also been reported in hypertensive subjects and in children of hypertensive parents.

Hypertension is rarely found in rural or «tribal» areas of Africa, but it is very common in African cities and in black populations in Britain and the United States. Whereas the rural/urban differences in Africa are clearly due to lifestyle and dietary factors, the finding that hypertension is commoner in black people compared with white people may have some genetic basis. There is some evidence from salt loading studies in medical students that black Americans are more susceptible to a given salt load than white Americans, and may be more sensitive to the beneficial effects of salt restriction[53].

There is increasing evidence that fetal influences, particularly birth weight, may be a determinant of blood pressure in adult life. For example, babies who are small at birth are more likely to have higher blood pressure during adolescence and to be hypertensive as adults. Babies who are small for their age are also more likely to have metabolic abnormalities that have been associated with the later development of hypertension and cardiovascular disease, such as insulin resistance, diabetes mellitus, hyperlipidaemia, and abdominal obesity (the «Barker hypothesis»). Insulin resistance almost certainly contributes to the increased prevalence of coronary disease seen in adults of low birth weight[53].

It is possible, however, that genetic factors influence the Barker hypothesis. Mothers with above average blood pressure in pregnancy give birth to smaller babies who subsequently develop above average blood pressure themselves and eventually hypertension.

It is entirely likely that the similarity of blood pressures in mother and child are genetic and, in a modern «healthy» society, unrelated to intrauterine undernutrition[53].

Figure 8: Possible mechanisms to explain why low birth weight babies are more likely to develop hypertension in later life[53]

Source: Beevers G, Lip GYH, O'Brien E. The pathophysiology of hypertension. BMJ. 2001 Apr 14;322(7291):912-6.

In hypertensive left ventricular hypertrophy, the ventricle cannot relax normally in diastole. Thus, to produce the necessary increase in ventricular input, especially during exercise, there is an increase in left atrial pressure rather than the normal reduction in ventricular pressure, which produces a suction effect as described above. This can lead to an increase in pulmonary capillary pressure that is sufficient to induce pulmonary congestion. The rise in atrial pressure can also lead to atrial fibrillation, and in hypertrophied ventricles dependent on atrial systole the loss of atrial transport can result in a significant reduction in stroke volume and pulmonary oedema. Exercise induced subendocardial ischaemia can also produce an exaggerated» impairment of diastolic relaxation of the hypertrophied myocardium[53].

HTN is usually asymptomatic in children. This asymptomatic characteristic justifies why 75% to 90% of prehypertension are not diagnosed[54]. Children with mild to moderate elevation of blood pressure are asymptomatic. Only severe hypertension is symptomatic, causing headache, visual changes, epistaxis, or nausea. Retinal changes observed in adults affected by hypertension are seen in less than 50 percent of paediatric patients[55]. On following table we have the possible physical findingsindicative of secondary cause of paediatric HTN:

Table IV: Physical findings indicative of secondary cause of paediatric HTN[15]

Source: Gregory L, Spiotta R. Hypertension in children and adolescents. Am Fam Physician. 2006;73(9):1158-68.

The preferred method for BP measurement is the auscultatory method using a mercury sphygmomanometer[19]. Other methods include:

Children over the age of 3years who are seen in medical care settings should have their BP measured at least once during every health care episode. Those below 3years should have their BP measured in special circumstances (Appendix IV)[19].

To confirm hypertension, the BP in children should be measured with a standard mercury sphygmomanometer, using a paediatric stethoscope(it should not be compressed by the cuff) placed over the brachial artery pulse, proximal and medial to the cubital fossa, and below the bottom edge of the cuff (i.e., about 2 cm above the cubital fossa).The use of the bell of the stethoscope may allow softer Korotkoff sounds to be heard better.

Preparation of the child for standard measurement can affect the BP level just as much as technique. Ideally, the child whose BP is to be measured should have avoided stimulant drugs or foods, have been sitting quietly for 5 minutes, and seated with his or her back supported, feet on the floor and right arm supported, cubital fossa at heart level[16,49]. The right arm is preferred in repeated measures of BP for consistency and comparison to standard tables and because of the possibility of coarctation of the aorta, which might lead to false (low) readings in the left arm[15,19]. Correct measurement of BP in children requires use of a cuff that is appropriate to the size of the child's upper right arm. The equipment necessary to measure BP in children of ages 3 through adolescence, includes child cuffs of different sizes and must also include a standard adult cuff, a large adult cuff, and a thigh cuff. The latter two cuffs may be needed for use in adolescents[19].

By convention, an appropriate cuff size is a cuff with an inflatable bladder width that is at least 40 percent of the arm circumference at a point midway between the olecranon and the acromion. For such a cuff to be optimal for an arm, the cuff bladder length should cover 80-100 percent of the circumference of the arm. Such a requirement demands that the bladder width-to-length ratio be at least 1:2[47].

Not all commercially available cuffs are manufactured with this ratio. Additionally, cuffs labelled for certain age populations (eg, infant or child cuffs) are constructed with widely disparate dimensions. Accordingly, the working group recommends that standard cuff dimensions for children be adopted (see Table V). BP measurements are overestimated to a greater degree with a cuff that is too small than they are underestimated by a cuff that is too large. If a cuff is too small, the next largest cuff should be used, even if it appears large. If the appropriate cuffs are used, the cuff-size effect is obviated[19].

SBP is determined by the onset of the «tapping» Korotkoff sounds (K1). Population data in children and risk-associated epidemiologic data in adults have established the fifth Korotkoff sound (K5), or the disappearance of Korotkoff sounds, as the definition of DBP. In some children, Korotkoff sounds can be heard to 0 mm Hg. Under these circumstances, the BP measurement should be repeated with less pressure on the head of the stethoscope. Only if the very low K5 persists should K4 (muffling of the sounds) be recorded as the DBP[19,46].

The standard device for BP measurements has been the mercury manometer. Because of its environmental toxicity, mercury has been increasingly removed from health care settings. Aneroid manometers are quite accurate when calibrated on a semi-annual basis and are recommended when mercury column devices cannot be obtained[19].

Source:- National High Blood Pressure Education Program Working Group on High Blood Pressure in Children and Adolescents. The fourth report on the diagnosis, evaluation, and treatment of high blood pressure in children and adolescents. Pediatrics. 2004 Aug; 114(2 Suppl 4th Report):555-76.

Its principle is based on BP calculation from pressure oscillations detected in the arm cuff. This method determines mean BP directly from the point of maximum oscillation. Neither SBP nor DBP is measured directly, but is calculated using an algorithm based on a putative relationship between the oscillations. Then, in cases in which the oscillation is shorter than usual, as is common in children, the potential for erroneous measurement increases. If an oscillometric method is applied, the monitor should have passed the validation procedure recommended by the British Hypertension Society, the AmericanAssociation for the Advancement of Medical Instrumentationor the European Society of Hypertension International Protocol which is very difficult.Therefore, if hypertension is detected by the oscillometric methods, it must be con?rmed by the auscultatory method[19,46].

Ultrasound transmitter and receiver is placed over brachial artery under blood pressure cuff. Doppler shift due to movement of blood beginning with systole up to diastole is recorded.In infants this technique is used to record systolic blood pressure. Ankle brachial index uses this technique, where in systolic pressure of brachial and posterior tibial artery is compared.

Developed by Penaz, work by principle of «unloaded arterial wall». Arterial pressure is detected by photo-plethysmograph under pressure cuff. Output of plethysmograph creates a servo loop, which rapidly changes cuff pressure such that artery is maintained in open state. Oscillatory pressure in cuff are measured.Cuff can be kept for 2 hours.

Once HTN has been confirmed, an extensive history and physical examination should be conducted to identify underlying causes and to detect any end organ damage[15].

History : A careful history of family history of HTN or CVD; sleep disordered breathing (snoring, obstructive sleep apnea); illicit drugs (tobacco, cocaine) and other over the counter medications should be obtained[12].

Physical examination: It should include BMI calculation; lower and upper limb BP measurement to rule out coarctation of the aorta; examination of the retina[12,15].

Laboratory and imaging tests should be conducted to screen for identifiable causes, detect comorbid conditions and evaluate end organ damage. This should proceed from simple tests that can be performed on an ambulatory setting to complex non-invasive and finally to invasive tests.

Usually findings from physical examination dictate the appropriate choice of tests(Appendix IV)[47]:

Source:- Lurbe E, Cifkova R, Cruickshank K, Dillon M. Management of high blood pressure in children and adolescent...?: Journal of Hypertension. J Hypertens. 2009;27:1719-42.

Managing childhood hypertension is directed at the cause of the elevated blood pressure and the alleviation of any symptoms. End-organ damage, comorbid conditions, and associated risk factors also influence decisions about therapy. Non pharmacologic and pharmacologic treatments are recommended based on the age of the child, the stage of hypertension, and response to treatment[16,44,47].

For children and adolescents with elevated BPlevel or stage 1 hypertension, therapeutic lifestyle changes are recommended[47]. These include weight control, regular exercise, a low-fat and low-sodium diet, smoking cessation, and abstinence from alcohol use[15]. Obesity increases the occurrence of hypertension threefold while favouring the development of insulin resistance, hyperlipidaemia, and salt sensitivity[57]. Significant obesity also increases the likelihood of LVH independent of blood pressure level[5,58]. Exercise has been shown to lower blood pressure in children but does not affect left ventricular function. Competitive sports are permitted for children with prehypertension, stage 1 hypertension, or controlled stage 2 hypertension in the absence of symptoms and end-organ damage[47]. Nevertheless, the NHBPEP has taken an aggressive stance on sodium restriction, recommending a sodium intake of 1,200 mg per day; a no-salt-added diet with more fresh fruits and vegetables combined with low-fat dairy and protein[19]. According to the DASH (Dietary Approaches to Stop Hypertension) food plan may be successful in lowering blood pressure in children. Increased intake of potassium and calcium also has been suggested as nutritional strategies to lower blood pressure [15]. Whatever lifestyle changes are recommended, a family-centered rather than patient oriented approach usually is more effective.

Reasons to initiate antihypertensive medication in children and adolescents include symptomatic hypertension, end-organ damage (e.g., LVH, retinopathy, proteinuria), secondary hypertension, stage 1 hypertension that does not respond to lifestyle changes, and stage 2 hypertensionwithout a clearly modifiable factor (e.g, obesity)[44,47]. In the absence of end-organ damage or comorbid conditions, the goal is to reduce blood pressure to less than the 95th percentile for age, height, and sex. When end-organ damage or coexisting illness is present, a blood pressure goal of less than the 90th percentile is recommended[19].

Drug therapy is always an adjunct to non-pharmacologic measures. According to the NHBPEP, pharmacotherapy should follow a step-up plan, introducing one medication at a time at the lowest dose, then increasing the dose until therapeutic effects are seen, side effects are seen, or the maximal dose is reached[19,55]. Only then should a second agent, preferably one with a complementary mechanism of action, be initiated. Long-acting medication is useful in improving compliance[35]. Diuretics and beta blockers have documented safety and effectiveness in children. Preferential use of specific classes of medications for certain underlying or coexisting pathology has led to the prescribing of ACE inhibitors or ARB in children with diabetes or CKD and beta-adrenergic or calcium channel blockers for children with migraines[15]. As with any chronic health issue, medical follow-up and appropriate monitoring are keys to long-term success (Appendix IV).

A hypertensive crisis (emergency or urgency) is a life threatening condition associated with severe hypertension. Hypertensive emergency is de?ned as severe hypertension complicated with acute target organ dysfunction (mainly neurological, renal or cardiac)[45]. Hypertensive urgency is de?ned as severe hypertension without acute target organ dysfunction. Children with hypertensive emergencies should be treated in an intensive care unit to ensure monitoring and support of the vital organs.The treatment strategy must be directed toward the immediate reduction of BP to reduce the hypertensive damage to the target organs, but not at a rate likely to cause hypo perfusion of vital organs by an excessively rapid reduction of BP (mainly cerebral hypo perfusion with neurological sequelae) [47]. In such situations, the BP should be reduced by more than 25% of the planned reduction over the first 8 hours, with the remainder of the planned reduction over the next 12 to 24 hours. The ultimate short-term BP goal in such patients should generally be around the 95th percentile. Appendix IVlists suggested doses for oral and intravenous antihypertensive medications that may treat patients with acute severe HTN[44].

Rx indicates prescription; Q, every; †, diet modification and physical activity; ‡,especially if younger, very high BP, little or no family history, diabetic, or other risk factors.

A pulmonary oedema with asystolia can brutally decompensate a moderate left ventricular overload in a newborn. It appears sometimes that the blood could be within normal limits or low controlled, rising after a reduction of the heart failure[43]. Signs and symptoms of target organ damage are present only in the late stages of the disease. Left ventricular hypertrophy (LVH) is the most common target organ abnormality found in childhood[58]. LVH is present in 34 to 38% of children with mild, untreated hypertension[58,59]. Paediatric patients with established LVH is an indicator to initiate or intensify antihypertensive therapy[41,58]

The vascular repercussion is potentially severe due to the risk of vascular rupture: intracerebral rupture in case of cerebral arteriovenous malformations, retinal haemorrhage (dramatic functionally) oraortic dissecting aneurysm. There are otherwise certain vasomotor phenomena which can aggravate a cerebral or renal ischemia[60].

Seizures can be rebel to anticonvulsants if HTN isn'tcontrolled. A cerebral haemorrhage sometimes massive, could be associated to hemiplegia or a cortical blindness, an intra-ventricular haemorrhage in the premature newborn, and a cerebral oedema responsible for an intracranial hypertension complicated in severe cases by a hypertensive encephalopathy[43].

Every severe HTN leads to lesions of nephro-angiosclerosis: necrosis of the afferent arteriole, glomerular hyalinisation. These lesions could lead to a kidney failure, prone to regression, at least a little, after control of HTN. Exceptionally in children, certain malignant HTN with nephro-angiosclerosis lead to a haemolytic and uremic syndrome with a rapidly irreversible kidney failure[60].

They are quite rare but severe: finite blindness following retinal haemorrhage,retinal detachment or optic atrophy secondary to a papillary oedema. The severity of lesions seen on fundoscopy is not linked to the oldness of the HTN nor the existence of any other visceral anomaly[61].

Several studies have been carried out worldwide to determine blood pressure profile and their risk factors in children.

· In 2004, Sorof et al screened 5102 children in the U.S.A aged 13-17years in 4ethnic distributions(white 44%,Hispanic 25%, African American 22%, and Asian 7%). The prevalence of HTN after the first, second and third screenings was 19.4%, 9.5%, and 4.5%.Overall, overweight prevalence was significantly associated, with significant variations between the ethnic distributions.They however, noted that the ethnic differences in the prevalence of hypertension were not significant after controlling for overweight[62].

· In 2004, Moura et al used the cross sectional methodology on 1253 children aged 7-17years in Brazil and observed a prevalence of HTN of 9.4%. They noticed blood pressure was significantly associated with overweight and obesity. However, no statistical differences were observed between males and females with regards to the prevalence of elevated blood pressure [63].

· In the U.S.A, Urrutia-Rojas et al in 2006 carried out a school based cross sectional study to determine the prevalence and associated factors of HTN on 1066 children aged 8-13years. They noted a 20.6% prevalence of HTN and HTN was significantlyassociated with overweight and obesity as well as African Americans which were more likely to have HTN than Caucasians[8].

· In 2010, Sharma et al in India, carried out a cross sectional study and screened 1085 school children aged 11-17years for HTN and found a prevalence of 5.9% HTN and 12.3% Prehypertension after 2 evaluations. In their study, prevalence of HTN in obese children was 46.5% and 17% in non-obese; urban and rural children had comparable rate of elevated BP-[64].

· In China, Xi Lu et al in 2013, carried out a school-based cross sectional study on 78,114 children and adolescents. In their study, both SBP and DBP were significantly increased in overweight and obese groups; and the prevalence of high SBP, DBP and hypertension(ranges from 8 to 26%) were markedly higher among overweight and obese children than normal weight groups[46].

· Flavio et al in 2016 in Brazil, conducted an observational cross sectional study on a sample of 157 students from the city of Petropolis aged from 10 to 19 selected randomly. In their study, the prevalence of HTN was 10.8% and there was a significant association with overweight and obesity as well as with the pressure of family history of hypertension[65].

· Nihaz et al in 2016 in India, carried out a cross sectional study on 1610 school children aged 5-10years from 6 schools of rural urban regions; and found a prevalence of HTN of 4.5% and pre-HTN of 5.8%. In their study, urban school children with hypertension were 7.52% against rural were 1-2%, pre hypertension in urban school children were 9.4% ,rural 1.84% Hypertension in males were 4.31% and in females were 4.65%. They also noted, a strong association between childhood obesity, family history of diabetes mellitus, ischemic heart disease and cerebrovascular accident; and childhoodhypertension[66].

· In 2017, Yide Yang et al in China, carriedout a national cross sectional survey on 62, 168 participants aged 6- 17years with complete data of body weight, height, and blood pressure; and found a prevalence of HTN of 10.2% and 8.9% for boys and girls, respectively. In their study, isolated systolic high blood pressure is the dominant high blood pressure subtype among Chinese boys aged 6-17 years and girls aged 12-17 years, while isolated diastolic high blood pressure was the most common high blood pressure subtype in girls aged 6-11 years; and boys with adiposity showed a higher risk of high blood pressure than their female counterpart[67].

· Espinosa et al in 2017 in Spain conducted a cross sectional study including a sample of 1,604 schoolchildren aged 4- 6 years belonging to 21schools from the provinces of Ciudad Real and Cuenca, Spain. The results show estimates of prevalence of HTN and prehypertension being 18.2% and 12.3% respectively, and was significantly associated to high levels of adiposity-[68].

· In South Africa in 2005, Monyeki et al carried out a longitudinal study to assess association of fat patterning with blood pressure in children aged 6-13years. They noted that the prevalence of HTN ranged from 1 to 5.8% and 3.1 to 11.4% for girls. A significant association between high diastolic BP and high BMI was noted, while children with low BMIs were less likely to be hypertensive[38].

· Harrabi et al in 2006, carried out a cross sectional study on 1559 children aged 5-15years in Tunisia. They noted 9.6% prevalence of HTN with no significant difference in prevalence between boys (9.2%) and girls (9.9%). Boys had higher mean SBP compared to girls. In both boys and girls, systolic pressure had a highly significant positive correlation with the height, weight, and triglyceride concentration-'''''''''''''''-[11].

· In Nigeria, Okoh et al in 2012, conducted a cross sectional study to evaluate the prevalence and severity of HTN in 1302 school children aged 6-12years. The prevalence of HTN was 4.7% and prehypertension was 4.6%. Prevalence of HTN was higher on females and a high BMI was significantly associated with HTN[23].

· In Congo, Ellenga et al in 2014 conducted a cross sectional study to determine the prevalence and associated risk factors of pre-HTN and HTN in school children at Brazzaville in Congo, where they screened 603 children and noted a prevalence of 10.1% during the first screening and 3.3% in the second screening for HTN;and 20.7% for prehypertension.Obesity and overweight as well the high economic level are greatly associated with HTN in this population'-[6].

· In 2015, Juliana et al in South Africa, conducted a study which utilized data from the Birth to Twenty cohort, which comprised a sample of 3273 children born in Soweto, Johannesburg in 1990.In this study, the overall point prevalence ranged from 9.2 to 16.4% for prehypertension and 8.4 to 24.4% for hypertension which showed a high prevalence of HTN which tracks from early childhood into adolescence - - [69].

· In 2017, Umar et al in Nigeria, carried out a multistage sampling technique which was used to select 2000 pupils from 66 primary schools in Kano aged 6-14years. This study showed a prevalence of HTN of 3%, higher in females as compared to males with a positive significant correlation with the body mass index-[70].

· Fotso in 2012, conducted a cross sectional study on 628 school children aged 7-19years in Yaounde. She noted that BP was high in 1 out of every 6 children with a prevalence of HTN of 2.2%. The mean SBP and DBP were 112#177;14mmHg and 69.7#177;10mmHg respectively'''''''''''''''''''''''`'''''''''''''[25].

· In 2014, Bissohong carried out a prospective-descriptive study from Sept 2014 to May 2015 on 769 school children aged 4-18years in Bertoua. The prevalence of HTN was 2.9% and was more prevalent in males than in females. Mean SBP and DBP were 106.8mmHg and 68.4mmHg respectively'''''''''''''''''''''''''''''''[24].

· Samain in 2015,carried out a community-based cross sectional study on 1313 primary school children aged 5-15years in Buea. The prevalence of hypertension was 3.2% and that of prehypertension was 7.6%. 3.5% of males and 2.9% of females were hypertensive. Hypertension was significantly associated with obesity. There was no significant association between hypertension and family history of hypertension and hypertension was of systolic predominance[26].

The study was carried out in public and private primary schools in the Mbankomo subdivision, in the Centre Region of Cameroon. Cameroon is divided into 10regions: Far North, North, Adamawa, Centre, Littoral, East, West, South, South West and North West Regions. The Centre which is our region of interest has Yaounde as capital. Mefou and Akono whichis one of its divisions covers an area of 1,329km² and had a population of 57,051inhabitants in 2001(according to the 2004 Cameroon statistical annual). It is made of 4subdivions: Akono, Bikok, Ngoumou and Mbankomo, with the latter being our area of interest. Mbankomo has a population of 20,305inhabitants and a surface area of 1,300 km².

The Mbankomo subdivision has a total of 71 primary schools(31 public schools and 40 private schools) with a total of 10,308 pupils in all her primary schools: 6,006 in public schools and 4,302 in private schools. A sample was thereby derived from these schools using a cluster sampling method.

The study was carried out over a period of six months (21^thNovember 2017 - 22^thMay 2018).

Primary school children inMbankomo subdivision found in theMefou and Akono division, Centre Region.

The sample size was calculated using the Cochran's formula for sample size for one proportion of a finite population. For that we used[71];

p= Prevalence of hypertension in primary school children of 3.2% in the study of Samain Nkendo (in primary school children in Buea) [26].

Using this approach, the minimum sample size was 298 pupils. Considering 10% missing data, 328 pupils were initially targeted.

The first stage consisted of conveniently selecting 13 primary schools or clusters (18% of 71 primary schools in the study area) by probability proportionate to size.

We used this method because the subdivision does not have the same number of primary schools in the rural and semi-urban settings. It was therefore, appropriate to consider the use of a random selection process where the probability of inclusion of each cluster in the sample, tend to be proportional to the size of the cluster.

This was done by listing all the schools (both public and private) in the 2 settings(rural and semi urban) irrespective of the method used for ordering them and, we sampled systematically as follows: The first school was selected randomly by balloting and thereafter every 7^thschool (K^th= 71/13) was selected until 13primary schools were obtained, as seen below:

In the second stage, our clusters were the 13 selected primary schools. Since the number of pupils enrolled in each of the 13 schools selected above were different, we used probability proportional to size to select participants by randomly selecting (13%) pupils in each class enrolled in each of the schools. This was done so that the final sample will proportionally represent each of the classes, each primary school, as well as each school setting.

This was done as follows: The study was explained to the pupils in each class (class 1-6) and verbal assent obtained. Thereafter a minimum of 13%of the pupils in that class were selected by balloting.

· Children with signed consent form by parents or tutors and who acceptedto participate in the study.

· Any child who because of a disability not permitting weight, height, or blood pressure takings as recommended by the WHO.

· Children taking medication known to lower blood pressure in whom a diagnosis of HTN has not been made.

The self-administered section of the questionnaire was filled by parents/guardians while the interviewer-administered section was filled by the investigator.

- The socio-demographic characteristics of the child (age, sex,type of school, class,school setting, milieu, profession and telephone number of legal tutor)

- Socio economic status[which is an adapted classification from therevisedKuppuswamy's socio-economic status scale- January 2015-[72](see APPENDIX IV)]where the projected family income was estimated from the Gross National Income (GNI) per capital.

- Medical record of Parents and other family members(family history of hypertension, obesity or overweight,diabetes)

A prior ethical clearance from the Ethical Committee of the Faculty of Medicine and Biomedical Sciences of the University of Yaounde I was obtained, as well as authorizations from the Divisional Delegation of Basic Education at Ngoumou and the Sub Divisional Inspectorate of Basic Education at Mbankomo. An informed note was addressed to the respective school authorities to the chosen schools in order to obtain their authorizations.

A meeting was organized to prepare the investigators made up of; a student nurse and a 7^th year student to plan data collection, as well as training sessions for anthropometric measurements.

The study involvedprimary school children and as such legally could not give consent. After explanation of the study in each class, a verbal and a written signed assent were obtainedfrom parents/guardians before inclusion in the study. Among the pupils who accepted to be part of the study, participants were selected by simple random sampling. Each of them was given a consent form and a questionnaire (English or French) to take home for their parents/guardian to fill and sign if they accepted that their children should participate in the study. Information was collected only from those who returned with signed consent form, correctly filled questionnaire and who also gave verbal assent.

Blood pressure was measured and classified according to the AAP (American Academy of Pediatrics) recommendations [44]. Before blood pressure measurements, pupils were familiarized to the instrument and the nature of the procedure was explained.

Blood pressure was measured in the sitting position on the right arm using the auscultatory method with a pediatric stethoscope, and a standard aneroid sphygmomanometer with appropriate cuff size covering at least 2/3^rd (80%) of the upper arm and encircling it completely (at least 40%). The child's right arm was supported at the level of the heart during measurements. This was the preferred arm because of consistency and comparison to standard tables and also because of the probability of decreased BP on the left arm caused by coarctation of the aorta.

The stethoscope was placed lightly over the brachial artery(if pressed too firmly against the artery, it might cause turbulence and the disappearance of sound, thus artificially reducing the diastolic pressure). The cuff was inflated to a pressure of 30mmHg above the level at which the radial pulse was no longer palpable. While slowly deflating the cuff (approximately 2-3mmHg per heartbeat), the Korotkoff phase I was listened while watching the blood pressure gauge. Korotkoff phase I was identified by the first pulse auscultated. The measurement was then recorded from the sphygmomanometer at which the sound first appeared; representing the participant's systolic blood pressure. While watching the sphygmomanometer, the cuff was continuously slowly deflated till an abrupt soft, indistinct, muffling sound was heard (Korotkoff phase IV). This sound was then continuously listened until it disappeared completely (Korotkoff phase V) and recorded; this represented the participant's diastolic blood pressure. The cuff was completely deflated and the child was allowed to rest.

For each participant, BP was measured twice in the same visit with a minimum of 30 seconds rest interval and the mean BP calculated. We waited for another 1-2minutes and repeated the blood pressure measurement procedure on the participant's opposite arm and if a measurement discrepancy existed between the 2arms, then arm the highest measurement was noted. BP readings were taken to the nearest 2mmhg. BP readings were classified according to the recommendations of AAP as follows:

· Elevated BP if SBP and/or DBP were between 90^th and 95^th percentile for age, height and sex or if SBP>120mmhg or DBP>80mmhg.

· Hypertensive if SBP and/or DBP were equal to or greater than the 95^th percentile for height, age and sex.

Participants who were hypertensive on the first visit were rechecked (had a repeated BP measurement) 2 times at intervals of 1 week to ensure persistent hypertension.The pupils diagnosed of hypertension underwent a urine dipstick test for proteinuria.

Eachhypertensive pupil was referred to the Mbankomo district hospital and a Pediatric Cardiologist for management and follow-up. At the end of the study, a list of all the hypertensive pupils diagnosed and their respective schools were sent to the Delegate of Basic Educationof the Mefou and Akono division in Ngoumou as well as the findings from our study.

Participants were weighed barefoot, standing still, without support and wearing light clothes(removed shoes and heavy clothing, such as sweaters) using a manual weighing scale and recorded in the nearest 0.1kg.

Height was measured using a wooden stadiometer calibrated in centimeters (cm) and recorded in the nearest 0.1cm. Each participant stood erect with no shoes on and with the occiput, shoulder, buttocks and calf touching the vertical position of the stadiometer.

The readings were recorded on a corresponding data collection sheet of each participant before going to the next. Weight and height were used to determine BMI. Pupils were categorized by age and sex using WHO BMI growth tables and charts(Appendix III).Pupils' heights were categorized to height percentile using WHO height for age and sex standard tables and charts (Appendix III).

Source :The Mother and Child Health and Education Trust. Taking the Weight-for-Height/Length - Anthropometric Measurements Techniques - Diagnosis of Acute Malnutrition - Mother, Infant and Young Child Nutrition & Malnutrition - Feeding practices including micronutrient deficiencies prevention, control of wasting, stunting and underweight [Internet]. 2017 [Cited 29 October 2017]. Available from: http://motherchildnutrition.org/malnutrition-management/integrated-management/taking-the-weight-for-height-length.html

· A data entry form with two sections (section one for the parents' and child's medical records and section two for blood pressure and anthropometric parameters).

· A paediatric stethoscope and paediatric aneroid sphygmomanometer (GIMA*) with various cuff sizes appropriate for mid upper arm circumference (< 8cm, 8-14cm, 14-21cm, >21cm).

· Microsoft® Office Excel 2013, SPSS standard version(20.0) for windows, WHO Anthro Plus version 1.0.4and Epi-info^TM version 3.5.4 software for data analysis and Microsoft® Office Word 2013 as the input software

· Co-directors:Associate Professor CHELO David,Associate Professor MAH Evelyn Mungyeh

The investigator was to note the collected data of each patient on the pre-established work sheet(Appendix I) and typed it down in Epi info 3.5.4, by making a view. Then, it was analysed using the Epi info 3.5.4and anthropometric data was analysed using WHO Anthro version 3.2.2. The graphs were produced with the use of Microsoft Excel 2013.

The quantitative variables were described using mean and standard deviation while the qualitative variables were described using frequencies and proportions.

Analysis were carried out to assess associations between each variable.Correlation between quantitative variables was described using Pearson's correlation coefficient (r).

Associations between qualitative variables weredescribed by comparing proportions using Chi-Square test(when an expected value is >5) and Fisher's exact test (when an expected value is <5). The force of association wasevaluated using the Odd's ratio and statistical significance was considered at P-value < 0.05.

Ø Quantitative variables: Age, Number of meals per day, fruit and vegetable consumption per week, sport practice duration per week, weight, height, level of education of legal tutor, birth weight.

· Blood pressure: The American form of blood pressure presentation was adopted as follows:

· BMI (according to WHO classification for assessment of nutritional status)'-[6]

- Monthly family income(FCFA) : =15,072 ; 15,073 - 45,217 ; 45,218 - 75,363 ; 75,364-113,045 ; 113,046 - 150,727 ; 150,728 - 301,454 ; =301,455

· Profession of legal guardian: Student, civil servant, private worker, informal, unemployed.

- Level of education of legal tutor:Higher education, Secondary (2^nd cycle), Secondary (1^stcycle), Primary, Illiterate

For this study, 1,754 consent forms and questionnaires were distributed to all the pupils enrolled in the 13 selected primary schools (private and public) in Mbankomo subdivision.422 (34%) pupils were excluded because of absence, poorly filled questionnaires and loss of follow up. Only 822 (66%) pupils were finally included in the study. The figure below represents the flow diagram of the sample population.

Of the 822 pupils recruited, 469 (57.1%) were femalesand353 (42.9%) were males, giving a sex ratio of 1.3.

The mean age was 9 #177; 2.5 years (with extremes from 5 to 17years). The most represented age range was 8-10 years (41.1%), and was followed by those aged 5-7 years (32.6%).

In this study, 681 (82.8%) pupils were from public schools and 141 (17.2%) pupils were from private schools.

A total of 466 (56.7%) pupils were from a semi urban setting and 356 (43.3%) pupils were from a rural setting.

The most represented classes were class 6 and class 5 in respectively 22.6% and 18.2%.

Out of the 822 legal tutors who took part in the study, only 96 correctly filled the section of the socio-economic status and 84 (87.5%) homes had the middle socio- economic status.

Out of the 822 pupils enrolled, 757 (92.1%) pupils had a normal BMI; 55 (6.7%) pupils were overweight; and 5 (0.6%) pupils were obese.

Out of the 60 pupils who were overweight/obese, 45 were highly represented in the age range of 5-10 years.

Out of the 60 pupils who had overweight/obesity, 37 were female out of which 5 were obese.

On the first screening, 55 (6.6%) pupils had an elevated BP level and 67 (8.0%) pupils were found to be hypertensive. On the second screening, one week after the first screening, 60 (7.3%) pupils had an elevated BP level and 29 (3.5%) were hypertensive. On the third screening, one week after the second screening, 67 (8.1%)pupils had an elevated BP level and 13 (1.6%) hypertensive.

Out of the 13(1.6%) hypertensive pupils, 12 (1.5%) had stage one hypertension and 1 (0.1%) had stage two hypertension.

VIII.4.3 Prevalence of Elevated BP and hypertension with respect to systolic blood pressure (SBP) and diastolic blood pressure(DBP)

The prevalence of elevated BP and HTN was predominantlysystolic in 68 (1.6%) pupils and in 13 (1.6%) pupils respectively.

VIII.4.4Distribution of Elevated BP and hypertension with respect to socio-demographic characteristics and anthropometric parameters

Table XIX: Prevalence of Elevated BP and hypertension with respect socio-demographic characteristics and anthropometric parameters

Hypertension was predominant in the age range 14-17 years in 13.0%, in females in 2.1%, in public schools in 1.7%, in semi urban in 1.7%, and in obese in 20%.

VIII.4.5Correlation of systolic and diastolic blood pressure withanthropometric parameters

SBP(r=0.17; p=0.000) and DBP (r=0.07; p=0.000) statistically increased with age (figures13 and 14 respectively).

Also, the SBP (r=0.18; p=0.000) and DBP (r=0.11; p=0.000) statistically increased withBMI (figures 14 and 15 respectively).

Scattered plot diagram showing a positive correlation of SBP and age (r=0.17; p=0.000).

Scattered plot diagram showing a positive correlation of DBP with age (r=0.07; p=0.000).

Scattered plot diagram showing a positive correlation of SBP with BMI (r=0.18; p=0.000)

Scattered plot diagram showing a positive correlation of SBP with BMI (r=0.11; p=0.000).

Out of the 13 hypertensive pupils who underwent the dipstick urine test for proteinuria, 12 (92.3%) pupils had protein traces in urine and 1 (7.7%) pupil had a high protein count in urine.

Out of the 13 hypertensive pupils who underwent the dipstick urine test for blood, none had blood found in the urine.

Among the socio demographic characteristics of the pupils analysed, only the age (above10 years old) was a significantly associated factor of hypertension (OR=8.36; CI₉₅=2.06-55.73; p=0.000). Gender had some association although not significant (p=0.120).

Out of 96 legal tutors who filled this section, the economic status was not an associated factor of hypertension (OR=0; CI₉₅=0-30.62; p=0.880).

Adding salt carried twice the risk but the association was not significant (p=0.210) same as not drinking enough water carried 3times more risk (p=0.070).

Of all the elements of physical exercise and sedentarity analysed, sports wasn't protective against HTN although not significant (p=0.360), while moving in a car and sleeping for =8hours carry relative risks although not significant (p=0.080 and p=0.220, respectively).

Of all the variables of the pupil's past history analysed, the birth weight <2500(OR=11.84; CI₉₅=2.43-44.13; p=0.000), the preterm delivery (OR=11.84; CI₉₅=2.43-44.13; p=0.000), the recurrent UTI (OR=7.99; CI₉₅=1.12-35; p=0.040), HTN in family (OR=4.51; CI₉₅=1.44-15.26; p=0.010) and overweight in family (OR=10.64; CI₉₅=3.04-48.29; p=0.000)were risk factors of hypertension. Meanwhile, born at term(OR=0.08; CI₉₅=0.02-0.41; p=0.000)was a protecting factor.

Excess weight (overweight and obesity) was an associated factor of hypertension (OR=11.98; CI₉₅=3.64-37.96; p=0.000).

Out of the factors that were significant in bivariate analysis, the pupil's age>10 years old(OR=6.4614; CI₉₅=1.2581 - 33.1841; p=0.0254), overweight in family (OR=7.4624; CI₉₅=1.6906 - 32.9401; p=0.008) and excess weight (OR=10.1069; CI₉₅=2.5094 - 40.7063; p=0.0011)persisted as risk factors of hypertension after multivariate analysis with logistic regression; and born at term(OR=0.0845; CI₉₅=0.0216 - 0.3307; p=0.0004) persisted asa protecting factor.

The study was a school-based cross-sectional analytic study carried out in 13 primary schools in Mbankomo subdivision found in theMefou and Akono division, Centre Region. A total of 822 children were enrolled using a two stage cluster sampling method. The study was carried out to determine the prevalence hypertension and its associated factors in primary school children in Mbankomo subdivision.

Even though the analysis carried out permitted us to determine the prevalence of hypertension, as well as the associated factors, we were confronted with some difficulties in the field. They include: refusal to participate in the study, poorly filled questionnaires, and absence from school on the days the BP and anthropometric measurements were to be taken.

The fact that we did not carry out urine dipstick test on all the pupils limited analysis on renal involvement in HTN.

The majority of legal tutors (88%) refused to give elements of their socioeconomic status, limiting its association with HTN in study.

There was a female predominance (57.1%) with a sex ratio of 1.3. This female predominance was equally described by Bissohong (54%) in Bertoua'''''''''''''''''''''''''''''''[24], Fotso(52%) in Yaounde '''''''''''''''''''''''`'''''''''''''[25]and Sadoh et al in Nigeria in 2014 (51.1%) -[74]. This predominance reflects that of the general population [75]. On the other hand, Samain in Buea (50.9%)[26], and Maj et al in India (56%) [76] found a male predominance.

The mean age of the pupils was 9 years with extremes of 5 and 17 years, and the most represented age group was 8-10 years. This age group is similar to that found by Samain[26], which corresponds to primary school age.

We found that, 82.8% of the pupils were from public schools, and 17.2% from private schools. This could be attributed to the fact that there are fewer private schools compared to public schools in the study area. This finding was equally noted by Bissohong in Bertoua'''''''''''''''''''''''''''''''[24](61% public vs 39% private), and Sadoh et al 2014 (54.9% public vs 45.1% private) -[74]. This was not the case in the study carried out by Samain in Buea (46.1% public vs 53.9% private) [26].

In this study, the pupils were predominantly from the semi urban setting (56.7%). This could be explained by the high number of parents from the rural setting who refused to participate in the study due to their low level of comprehension on its necessity, and the absence of many pupils from school during data collection. This predominance was likewise in Nihaz et al's study 2016 in India [66].

Considering the socioeconomic status, only 12% of the study populationresponded with 87.5% being from a middle class household. It could be that the few who responded were those who understood the importance of the study.Our findings are in sharp contrast toBadawi et al in 2012 in Egypt-[77] with 48% of pupils from a middle class homeswhile Sadoh et al -[74] in Nigeria, noted more children from lower class homes.

The BMI as recommended by the WHO was used to classify the nutritional status in our study population, with excess weight known to be an associated risk factor to cardiovascular diseases '-[6].Excess weight was noted in 7.3% of the pupils (6.7% overweight and 0.6% obese). This occurred predominantly within the 5- 7 years age group. This figure is lower compared to findings made by other authors in Cameroon: 32.9%, 20.4% and 31% by Mekone, Bissohong and Samain respectively[24, 26, 78]. This figure is still lower compared to findings made by other African and chinese authors -[49,70,79]. The gap of the prevalence of excess weight between this study and other studies could be explained principally by the fact that, our study was carried out mainly in rural and semi urban setting where as the others carried out in urban settings: probably because of reduced physical activity and overconsumption of processed and energy-dense foods.

The classification of BP levels in this study was done according to the Guidelines of the American Academy of Pediatrics in 2017: Following these guidelines, 90.3% of the pupils had a normal BP level, 8.1% ofpupils had an elevated BP level and 1.6% hypertensive.This prevalence of HTN was lower than the levels reported by Fotso in 2013'''''''''''''''''''''''`'''''''''''''[25], Bissohong in 2015'''''''''''''''''''''''''''''''[24], and Samain in 2016 [26]. Higher prevalences have equally been reported in other African studies ranging from 3.5% to 10.8% (reported byFarah et al in 2014 in Uganda, Frances et al in 2017 in Nigeria andMuhihi et al in 2018 in Tanzania respectively) -[81-83]. Again, higher prevalences have also been described by some authors around the world [8,84,85]. Kishorkumar et al carried out a study aimed at determining the prevalence of HTN among 310 school children in a rural area of Tamil Nadu in India, and showed a prevalence of HTN of 10% and preHTN of 14.2%[86]. The difference between these prevalences and ours, could be attributed to the fact that the sample sizes were lower than ours, the studies were carried out in urban settings and the authors used the United States-based 2004 Task Force Report Update and French Reference Criteria which all tend to overestimate the BP.In the same light, genetic predisposition and sedentarity marked by more obese children in other studies mightequally contribute to this prevalence gap.However, a lower prevalence of 1% and 0.6% was determined by Adrogue et al in 2001 and Goon et al in 2013 respectively -[87,88], which could be due to the use of either an automated BP device which underestimates DBP by about 2.1mmHg or the use of a different reference critera: Second Task Force recommendation which underestimates BP.

In our study, HTN was predominantly systolic in a proportion of 1.6% compared to 0.4% that was diastolic. Similar results were noted in other studies[26,85,89]. This difference could be due to the increase in the activation of the sympathetic nervous system due to stress which elevated SBP of pupils in our study[80].This finding was contrary to that observed by Bissohongwho reported diastolic predominance in a proportion of 2.6% for elevated DBP and 0.9% for elevatedSBP'''''''''''''''''''''''''''''''[24].

In our study population, the prevalence of HTN was higher within the age range 14 - 17 years. Bhuvaneswar et al[90]and many other studies noted high BP levels at preadolescence and adolescence [8,85,89,91].This could be attributed to an increase in body mass and gonadal hormones (testosterone, oestrogene and progesterone) in pubertal period.

The prevalence of hypertension was slightly higher in females 10 (2.1%) than in males 3 (0.8%) in our study. A similar finding was noted by Okoh et al in Nigeria in 2012 [23],Samain in 2016 [26].

The difference prevalences between the male and the female gender could be due to the fact that, there is an increase in large artery stiffness with age, and an onset of body fat mass deposition which starts earlier in girls than in boys during prepuberty and puberty. However, the changes over time in artery stiffness and fat deposition are such that no gender differences are observed in postpuberty [92]. Whereas Goon et al in 2013 [88],and Bissohong in 2015 '''''''''''''''''''''''''''''''[24],noted higher prevalences in males.

The prevalence of HTN was higher among pupils attending public schools with a proportion of 1.7% compared to 0.7% in those attending private schools in our study. Samain in 2016[26]in Buea, equally reported a high prevalence in public schools. This could be explained by public schools authorities who less encouraged physical activities in our study. However, some other studies found a higher prevalence in private schools'''''''''''''''''''''''''''''''[24,84,86]. According to Sarala et al [84], the high prevalence of hypertension in private school children could be attributed to decreased physical activity,change in nutritional habits and life style change.

In our study, HTN was reported to be more present in pupils attending schools in a semi urban setting(1.7%) compared to those attending in a rural setting(1.4%).Nihaz et al in 2016 in a study whose objective wasto determine the prevalence of hypertension and risk factors amongschool children in Kerala, India, demonstrated that the prevalence of combined hypertension and pre-hypertension (BP>90th percentile) was high in the urban areas (16.2%)compared to the rural areas (2.89%) [66]. This was explained by the fact that, a middle to high economic status mostly found in urban homes has got major effect on the nutritional status of pupils. The decreased physical activity in children and adolescents have been related mainly to, computer games, video games, internet gazing, television and movie viewing, overemphasis on academic excellence, and increasing automated transport [66,93].

Out of 13 pupils who were hypertensive, 20% were obese, and 9.0% were overweight. Muhihi et al in Tanzania[83] found that, 52.2% of the children were obese and 27.3% were overweight. It has been shown that excess weight during childhood is a risk factor for systolic hypertension, dyslipidemia, and insulin resistance, suggesting that reduction of the excessive rate of weight gain may exert beneficial effects on blood pressure[66,94,95].

We noted in this study that, SBP and DBP significantly increased with age. Previous reports confirmed this relationship -[26,74]. Age-related increase in blood pressure is partly attributable to increasing weight with age[83]. This positive correlation could also be due to a progressively increased risk of occurring secondary risk factors of elevated BP with age.

The SBP and DBP also,significantly increased with BMI in our study. Other studies observed a similar finding with a significant correlationof BMI with SBP and DBP-'''''''''''''''''''''''`''''''''''''''''''''''''''''''''''''''''''''-[24-26,74,96]. The correlation between BP and BMI in children may highlight the development of metabolic syndrome[83].

On bivariate analysis, the characteristics which had a statistically significant influence on HTN were; the age, the birth weight, the term, the past medical history of recurrent UTI, family history of HTN and overweight, and excess weight.

In multivariate analysis, the independent factors associated with HTN were; the pupil's age>10 years old,family history of overweight, andexcess weight. On the other hand,being born at termwas protective.

In our study, pupils older than 10 years were strongly associated to hypertension (p=0.0254). This result is similar to that reported by certain authors notably Bissohong in 2015 in Bertoua'''''''''''''''''''''''''''''''[24]. Juliana et al in 2015 reported that the majority of hypertensive cases were preadolescents and adolescents (p<0.001) - - [69]. In Muhihi et al's study in 2018 in Tanzania, the prevalence of elevated BP was higher among children aged more than 10 years compared to those aged 10 years or less (p = 0.0029)[83]. This can be explained by the observed trend of increasing blood pressure with increase in body size,probable secondary risk factors, weight and sexual maturity which tends to occur with increasing age'''''''''''''''''''''''''''''''[82].

The family history of overweight was strongly associated to HTN in our study(p=0.008). This was not the case in Bissohong's study, which showed no statistically significant association '''''''''''''''''''''''''''''''[24]. According to Kanciruk et al, family history of obesity can be considered to be both environmental and biological in nature[97]. In terms of environmental risk, parents, in particular mothers, tend to ingrain their personal eating habits as well as their perceptions of weight to their children and, in terms of its biological nature, the genetic influence of overweight/obesity may predispose children to developing this condition. This condition is known to be a precursor of cardiovascular diseases and particularly in HTN.

The present study observed that, the pupils who had excess weight (overweight and obesity) had a higher prevalence of HTN compared to those who didn't have (10% vs 0.9% respectively). We also noted a statistically significant association between excess weight and HTN (p=0.0011). This finding was consistent with that of Samain(p=0.000)[26], Bissohong (p=0.02) '''''''''''''''''''''''''''''''[24], and Arun et al (p=0.001) [91]. This association could be attributable to over activation of the renin-angiotensin and sympathetic nervous systems; insulin resistance; and abnormality in vascular structure and function observed in obese children [94].

Pupils born at term were less likely to be hypertensive. In fact, delivery at term was protective of HTN (p=0.0004). Most studies indicated prematurity as a risk factor of HTN [98,99].The mechanisms by which BP levels appear to be elevated in children and young adults who were preterm are not fully understood. The possible contributing factors include impaired morphological development of glomeruli and fewer nephrons on the basis of interrupted kidney development resulting in small kidneys, microvascular growth arrest and rarefaction building up peripheral vascular resistance [99]. We want to note the subjective nature of reporting of term and preterm delivery because we did not have access to the hospital delivery notes of the pupils from their legal tutors. We could not find any study associating birth at term with HTN.

At the end of our study, we can say that our different objectives have been attained. We can then draw the following conclusions:

· The mean age of the pupils enrolled in the study was 9years (extremes from 5-17years) and the most represented age range was 8-10 years (41.1%). Females were mostly represented in 57.1% giving a sex ratio of 1.3. Pupils mostly attended public schools in 82.8% and were mostly from a semi urban setting in 56.7%. The most represented class was class 6 in 22.6%. Most legal tutors carried out liberal professions (49.8%) and the most represented socio economic status was that of the middle class in 87.5%.

· The prevalence of hypertension was 1.6% (with 1.5% in stage I and 0.1% in stage II) and that of elevated BP was 8.1%. Hypertension was predominantly systolic in 1.6% anddiastolic in 0.4%. There was a positive correlation between age, BMI, and blood pressure.

· After multivariate analysis with logistic regression, only the age> 10years, family history of overweight,excess weight persisted as risk factors of HTN and born at term a protecting factor.

· Integrate blood pressure monitoring in children as part of routine examination during routine health/sick medical visits.

· Encourage healthy eating habits, manual labour and ensure physical activity at home.

1. World Health Organization. Global brief on hypertension [Internet]. 2013 [Cited 2017 July 24]. Available from: www.who.int

2. Giacomo DS, Bucher BS, Tschumi S. Hypertension chez l'enfant et l'adolescent. Rev Méd Suisse.2011; 7: 1041-2.

3. Tej KM, Stapleton FB, Kim SM. Definition and diagnosis of hypertension in children and adolescents [Internet]. Uptodate. 2011 [Cited 2017 March 24]. Available from: http://cursoenarm.net/UPTODATE/contents/mobipreview.html

4. Rahimi K, Emdin CA, MacMahonS. The Epidemiology of Blood Pressure and Its Worldwide Management. Circ Res. 2015 Mar 13; 116(6):925-36

5. Verma M, Chhatwal J, George SM.Obesity and hypertension in children. Indian Pediatrics. 1994 Sep; 31(9):1065-9.

6. Ellenga MBF, Okoko AR, Mabiala Babela JR, Ekouya Bowassa G, Gombet TR, Kimbally-Kaky SG. Prehypertension and Hypertension among Schoolchildren in Brazzaville, Congo. Int J Hypertens. 2014; 2014: 803690.

7. Feber J, Ahmed M. Hypertension in children: new trends and challenges. Clin Sci. 2010;119(4):151-61.

8. Urrutia-Rojas X, Egbuchunam CU, Bae S, Menchaca J, Bayona M, Rivers PA, et al. High blood pressure in school children: prevalence and risk factors. BMC Pediatrics. 2006; 6(1):32.

9. World Health Organization. Causes of death 2008: data sources and methods [Internet]. 2011 [Cited 2017 March 13]. Available from: www.who.int/healthinfo/global_burden_disease/cod_2008_sources_methods.pdf

10. Lim SS, Theo V, Flaxman AD, Goodarz D, Shibuya K, Adair-Rohani H, et al . A comparative risk assessment of burden of disease and injury attributable to 67 risk factors and risk factor clusters in 21 regions, 1990-2010: a systematic analysis for the Global Burden of Disease Study 2010. Lancet. 2012 Dec 15; 380(9859): 2224-60.

11. Harrabi I, Belarbia A, Gaha R, Essoussi AS, Ghannem H. Epidemiology of hypertension among a population of school children in Sousse, Tunisia. Can J Cardiol. 2006Mar;22(3):212-6.

12. Pinto A, Roldan R, Sollecito TP. Hypertension in Children: An Overview. J Dent Educ. 2006 Jan;70(4):434-40.

13. Lo JC, Sinaiko A, Chandra M, Daley MF, Greenspan LC, Parker ED, et al. Prehypertension and Hypertension in Community-Based Pediatric Practice. Pediatrics. 2013 Feb;131(2):415.

14. Gupta-Malhotra M, Banker A, Shete S, Hashmi SS, Tyson JE, Barratt MS, et al. Essential Hypertension vs. Secondary Hypertension Among Children. Am J Hypertens.2015Jan;28(1):73.

15. Luma GB, Roseann TS. Hypertension in Children and Adolescents - Am Fam Physician. Am Fam Physician. 2006 May;73(9):1558-68.

16. Riley M, Bluhm B. High Blood Pressure in Children and Adolescents. Am Fam Physician. 2012Apr;85(7):693-700.

17. Patel N, Walker N. Clinical assessment of hypertension in children. Clinical Hypertension. 2016; 22:15

18. Singh D, Akingbola O, Yosypiv I, El-Dahr S. Emergency Management of Hypertension in Children. Int J Nephrol. 2012; 2012:1-15.

19. National High Blood Pressure Education Program Working Group on High Blood Pressure in Children and Adolescents. The fourth report on the diagnosis, evaluation, and treatment of high blood pressure in children and adolescents. Pediatrics. 2004 Aug; 114(2 Suppl 4th Report):555-76.

20. Amritanshu K, Kumar A, Pathak A, Neha G, Banerjee DP. Prevalence and risk factors associated with hypertension in children and adolescents. Pediatric Oncall Journal. Apr-Jun 2015; 12: 2.

21. Salman Z, Kirk GD, DeBoer MD. High Rate of Obesity-Associated Hypertension among Primary Schoolchildren in Sudan. Int J Hypertens. 2010 Dec; 2011:629492.

22. Ugwuja EI, Ezenkwa US, Nwibo AN, Ogbanshi M, Idoko O, Nnabu R. Prevalence and determinants of hypertension in an agrarian rural community in Southeast Nigeria. Ann Med Health Sci Res. 2015Jan;5(1):45.

23. Okoh BA, Alikor EA, Akani N. Prevalence of hypertension in primary school-children in Port Harcourt, Nigeria. Paediatr Int Child Health. 2012 Nov;32(4):208-12.

24. Bissohong K. Profil Tensionnel des Enfants et Adolescents en milieu Scolaire dans la Ville de Bertoua[Memoire]. Universite de Yaounde I; 2014.

25. Fotso T. Etude de la Relation entre le Profil Ponderal et le Profil tensionnel dans une population scolaire de la vile de Yaounde [Thesis]. Universite Des Montagnes; 2012.

26. Samain NC. Prevalence and Risk Factors of Hypertension in Primary School Children in Buea Health District[Thesis]. University Of Buea; 2015.

27. WHO/ISH. 1993 guidelines for the management of mild hypertension: memorandum from a WHO/ISH meeting. Bull World Health Organ. 1993;71(5):503-17.

28. Inter-Agency and, Expert Group on SDG Indicators (IAEG-SDGs). SDG Indicators -- SDG Indicators [Internet]. 2017 [Cited 2017 June 01]. Available from: https://unstats.un.org/sdgs/iaeg-sdgs/

29. WHO. WHO | WORLD HEALTH REPORT 2002 [Internet]. 2002 [Cited 2017 June 01]. Available from: http://www.who.int/whr/2002/en/whr02_en.pdf

30. WHO. HEALTH FOR THE WORLD'S ADOLSCENTS-A second chance in the second decade [Internet]. 2014 [Cited 2017 November 08]. Available from: http://www.who.int/maternal_child_adolescent/documents/second-decade/en/

31. UNICEF. UNICEF - The State of the World's Children: Special Edition Celebrating 20 Years of the Convention on the Rights of the Child [Internet].2009 [Cited 2017 June 01]. Available from: https://www.unicef.org/rightsite/sowc/fullreport.php

32. McNiece KL, Poffenbarger TS, Turner JL, Franco KD, Sorof JM, Portman RJ. Prevalence of Hypertension and Pre-Hypertension among Adolescents. J Pediatr. 2007Jun;150(6):640-644.e1.

33. Hansen ML, Gunn PW, Kaelber DC. Underdiagnosis of Hypertension in Children and Adolescents. JAMA. 2007Aug;298(8):874.

34. Fallah Z, Djalalinia S, Qorbani M, Farzadfar F, Kelishadi R. A Systematic Review of Studies on Blood Pressure in Iranian Pediatric Population: First Report From the Middle East and North Africa. Iran J Pediatr. 2016 Apr; 26(2): e4496.

35. Din-Dzietham R, Liu Y, Bielo M-V, Shamsa F. High blood pressure trends in children and adolescents in national surveys, 1963 to 2002. Circulation. 2007Sep;116(13):1488-96.

36. Basiratnia M, Derakhshan D, Ajdari S, Saki F. Prevalence of childhood obesity and hypertension in south of Iran. Iran J Kidney Dis. 2013Jul;7(4):282-9.

37. Buch N, Goyal JP, Kumar N, Parmar I, Shah VB, Charan J. Prevalence of hypertension in school going children of Surat city, Western India. J Cardiovasc Dis Res. 2011;2(4):228-32.

38. Monyeki KD, Kemper HCG, Makgae PJ. The association of fat patterning with blood pressure in rural South African children: the Ellisras Longitudinal Growth and Health Study. Int J Epidemiol. 2006Feb;35(1):114-20.

39. Muntner P, He J, Cutler JA, Wildman RP, Whelton PK. Trends in Blood Pressure Among Children and Adolescents. JAMA. 2004May;291(17):2107-13.

40. Flynn J. The changing face of pediatric hypertension in the era of the childhood obesity epidemic. Pediatr Nephrol. 2013Jul;28(7):1059-66.

41. Rosner B, Prineas R, Daniels SR, Loggie J. Blood pressure differences between blacks and whites in relation to body size among US children and adolescents. Am J Epidemiol. 2000May;151(10):1007-19.

42. Chirag B, Chavda J, Kakkad MK, Damor P. A Study of Prevalence of Hypertension in School Children. Gujarat Medical Journal. 2013Dec; 68: 2.

43. André J-L. Hypertension artérielle chez l'enfant et l'adolescent. EMC - Cardiol-Angéiologie. 2005Nov;2(4):478-90.

44. Flynn JT, Kaelber DC, Baker-Smith CM, Blowey D, Carroll AE, Daniels SR, et al. Clinical Practice Guideline for Screening and Management of High Blood Pressure in Children and Adolescents. Pediatrics. 2017;140(3):e20171904.

45. Ashish B, Cynthia B, Monesha GM, Joshua S. Blood pressure percentile charts to identify high or low blood pressure in children. BMC Pediatrics. (2016);16:98.

46. Chiolero A, Bovet P, Paradis G, Paccaud F. Has blood pressure increased in children in response to the obesity epidemic. Pediatrics. 2007Mar;119(3):544-53.

47. Lurbe E, Cifkova R, Cruickshank K, Dillon M, Ferreira I, Kuznetsova T, et al . Management of high blood pressure in children and adolescents: Recommendations of the European Society of Hypertension. J Hypertens. 2010Jul; 27:1719-42.

48. Calhoun DA, Harding SM. Sleep and hypertension. Chest. 2010 Aug;138(2):434-43.

49. Lu X, Shi P, Luo C-Y, Zhou Y-F, Guo CY, Wu F. Prevalence of hypertension in overweight and obese children from a large school-based population in Shanghai, China. BMC Public Health. 2013 Jan; 13:24.

50. Falkner B, Gidding SS, Portman R, Rosner B. Blood pressure variability and classification of prehypertension and hypertension in adolescence. Pediatrics. 2008 Aug;122(2):238-42.

51. Silbernagl S, Lang F. Atlas de Poche - Physiopathologie.13th edition. Lavoisier; 2015.

52. Guyton AC, Hall JE. Textbook of Medical Physiology. 9th ed. Philadelphia?: W.B. Saunders; 1996.

53. Beevers G, Lip GYH, O'Brien E. The pathophysiology of hypertension. BMJ. 2001Apr;322(7291):912-6.

54. Rahman AJ, Qamar FN, Ashraf S, Khowaja ZA, Tariq SB, Naeem H. Prevalence of hypertension in healthy school children in Pakistan and its relationship with body mass index, proteinuria and hematuria. Saudi J Kidney Dis Transpl. 2013 Mar;24(2):408-12.

55. Kollias A. Hypertension in children and adolescents. World J Hypertens. 2011;1(1):15.

56. Bilagi DU. Techniques of blood pressure measurement. (Auscultatory, Oscillometric, Ultrasound, finger cuff method of Penaz) and Auscultatory gap [Internet]. Heart And Teeth. 2012 [Cited 23 October 2017]. Disponible sur: http://bilagi.org/blog/2012/07/03/techniques-of-blood-pressure-measurement-auscultatory-oscillometric-ultrasound-finger-cuff-method-of-penaz-and-auscultatory-gap/

57. Genovesi S, Brambilla P, Giussani M, Galbiati S, Mastriani S, Pieruzzi F, et al. Insulin resistance, prehypertension, hypertension and blood pressure values in paediatric age. J Hypertens. 2012Feb;30(2):327-35.

58. Kavey RE. Left ventricular hypertrophy in hypertensive children and adolescents: predictors and prevalence. Curr Hypertens Rep. 2013Oct;15(5):453-7.

59. Franks PW, Hanson RL, Knowler WC, Sievers ML, Bennett PH, Looker HC. Childhood Obesity, Other Cardiovascular Risk Factors, and Premature Death. N Engl J Med. 2010Feb;362(6):485-93.

60. Van Itallie TB. Health implications of overweight and obesity in the United States. Ann Intern Med. 1985Déc;103(6 ( Pt 2)):983-8.

61. Sebire G, Husson B, Lasser C, Tardieu M, Dommergues JP, Landrieu P. Encéphalopathie induite par l'hypertension artérielle: aspects cliniques, radiologiques et thérapeutiques. Arch Pédiatr. 1995;2(6):513-8.

62. Sorof JM, Lai D, Turner J, Poffenbarger T, Portman RJ. Overweight, ethnicity, and the prevalence of hypertension in school-aged children. Pediatrics. 2004 Mar;113(3 Pt 1):475-82.

63. Moura AA, Silva MAM, Ferraz MRMT, Rivera IR. Prevalência de pressão arterial elevada em escolares e adolescentes de Maceió. J Pediatr (Rio J). 2004Feb;80(1):35-40.

64. Sharma A, Grover N, Kaushik S, Bhardwaj R, Sankhyan N. Prevalence of hypertension among schoolchildren in Shimla. Indian Pediatr. 2010Oct;47(10):873-6.

65. Figueirinha F, Gesmar VHH. High Blood Pressure in Pre-Adolescents and Adolescents in Petrópolis: Prevalence and Correlation with Overweight and Obesity . Int. J. Cardiovasc. Sci. 2017; 30(3): 243-50.

66. Naha NK, John M, Cherian V. Prevalence of hypertension and risk factors among school children in Kerala, India. Int J Contemp Pediatr. 2016;3(3)931-8.

67. Yang Y, Dong B, Wang S, Dong Y, Zou Z, Fu L, et al. Prevalence of high blood pressure subtypes and its associations with BMI in Chinese children: a national cross-sectional survey. BMC Public Health. 2017Jun; 17:598.

68. Martín-Espinosa N, Díez-Fernández A, Sánchez-López M, Rivero-Merino I, Lucas-De La Cruz L, Solera-Martínez M, et al. Prevalence of high blood pressure and association with obesity in Spanish schoolchildren aged 4-6 years old. PLoS ONE.2017Jan;12(1): e0170926.

69. Kagura J, Adair LS, Musa MG, Pettifor JM, Norris SA. Blood pressure tracking in urban black South African children: birth to twenty cohort. BMC Pediatr. 2015 Jul;15:78.

70. Umar Also, Asani M, Muuta I. Prevalence of elevated blood pressure among primary school children in Kano Metropolis, Nigeria. Nig J Cardiol. 2016; 13(1): 57-61.

71. Charan J, Biswas T. How to Calculate Sample Size for Different Study Designs in Medical Research. Indian J Psychol Med. 2013;35(2):121-6.

72. Guru Raj MS, Shilpa S, Maheshwaran R. Revised socio-economic status scale for urban and rural india - revision for 2015. Socioeconomica. 2015; 4(7): 167-74.

73. The Mother and Child Health and Education Trust. Taking the Weight-for-Height/Length - Anthropometric Measurements Techniques - Diagnosis of Acute Malnutrition - Mother, Infant and Young Child Nutrition & Malnutrition - Feeding practices including micronutrient deficiencies prevention, control of wasting, stunting and underweight [Internet]. 2017 [Cited 29 October 2017]. Available from: http://motherchildnutrition.org/malnutrition-management/integrated-management/taking-the-weight-for-height-length.html

74. Sadoh WE, Omuemu VO, Sadoh AE, Iduoriyekemwen NJ, Adigweme IN, Owobo AC, et al. Blood pressure percentiles in a group of Nigerian school age children. Niger J Paed.2014; 41 (3):223 -8.

75. Live Cameroon population [Internet]. 2018 [Cited 15 May 2018]. Available from: htttp://countrymeters.info/en/Cameroon

76. Maj DR, Kushwaha AS, Kotwal A, Basannar DR, Mahen ACA. Study of blood pressure pro?le of school children 6-15 years in a rural setting of Maharashtra. Med JArmed Forces India. 2012; 68:222-5.

77. Badawi NES, Barakat AA, Sherbini SAE, Fawzy HM. Prevalence of overweight and obesity in primary school children in Port Said city. Gaz Egypt Paediatr Assoc . 2013; 61:31-36.

78. Mekone N. Facteurs de risque de la surcharge pondérale chez les adolescents âgés de 10 à 15 ans scolarisés dans les établissements secondaires de Yaoundé [Memoire]. Universite de Yaounde I; 2014.

79. Pangani IN, Kiplamai FK, Kamau JW, Onywera VO. Prevalence of Overweight and Obesity among Primary School Children Aged 8-13 Years in Dar es Salaam City, Tanzania. AdvPrev Med. 2016;2016: 1345017.

80. Souza CB, Dourado CS, Mill JG, Salaroli LB, Molina MDCB. Prevalence of Hypertension in Children from Public Schools. Int J Cardiovasc Sci. 2017; 30(1):42-51.

81. Kidy F, Rutebarika D, Lule SA, Kizza M, Odiit A, Webb EL, et al. Blood pressure in primary school children in Uganda: a cross-sectional survey. BMC Public Health. 2014; 14:1223.

82. Okpokowuruk FS, Akpan MU, Ikpeme EE. Prevalence of hypertension and prehypertension among children and adolescents in a semi-urban area of Uyo Metropolis, Nigeria. Pan Afr Med J. 2017; 28:303.

83. Muhihi AJ, Njelekela MA, Mpembeni RNM, Muhihi BG, Anaeli A, Chillo O. Elevated blood pressure among primary school children in Dar es salaam, Tanzania: prevalence and risk factors. BMC Pediatrics. 2018; 18:54.

84. Sabapathy S, Nagaraju BA, Bhanuprakash CN. Prevalence of childhood hypertension and pre-hypertension in school going children of Bangalore rural district: a cross sectional study. Int J Contemp Pediatr. 2017 Sep; 4(5):1701-4.

85. Manoja KD, Bhatia V, Anupam S. Prevalence of hypertension in urban school children aged 5 to 10 years in North India. Int J Contemp Pediatr. 2017 Nov; 4(6):2055-9.

86. Kishorkumar D, Stalin P, Prasad RV, Singh Z. Prevalence of Hypertension Among School Children in a Rural Area of Tamil Nadu. Indian Pediatr. 2016 Feb; 53(2):165-6.

87. Adrogue HE, Sinaiko AR. Prevalence of Hypertension in Junior High School-Aged Children: Effect of New Recommendations in the 1996 Updated Task Force Report. Am JHypertens. 2001 May; 14(5 Pt 1):412-4.

88. Goon D, Amusa L, Mhlongo D, Khoza L, Anyanwu F. Elevated Blood Pressure among Rural South African Children in Thohoyandou, South Africa. Iranian J Publ Health.2013May; 42(5):489?96.

89. Veena KG, Prasanna MP, Pattanshetty S, Asha K, Balakrishnan A, Mishra T, et al. Prevalence of hypertension in the paediatric population in Coastal South India. Australas Med J. 2010; 3(11): 695?8.

90. Bhuvaneswari M, Ramaprasad GS. Biophysical profile of blood pressure in urban healthy school children- a cross sectional study. J Evid Based Med Healthc. 2018; 5(9): 749-52.

91. Arun DJ, Kavinilavu R. A study of risk factors associated with hypertension among the school going children in Puducherry. Int J Community Med Public Health. 2018 Feb; 5(2):764-8.

92. Gianvincenzo B, Carmela C, Russo MD, Russo P, Nappo A, Fabio L, et al. Gender-Related Differences in the Relationships Between Blood Pressure, Age, and Body Size in Prepubertal Children. Am J Hypertens. 2008 Sep; 21(9):1007-10.

93. Agyemang C, Redekop WK, Owusu-Dabo E, Bruijnzeels MA. Blood pressure patterns in rural, semi-urban and urban children in the Ashanti region of Ghana, West Africa. BMC Public Health. 2005; 5:114.

94. Sorof J, Daniels S. Obesity Hypertension in Children A Problem of Epidemic Proportions. Hypertension [Internet]. 2002 [cited 20 February 2018]. Available from: http://www.hypertensionaha.org

95. Brady TM. Obesity-Related Hypertension in Children. Front Pediatr. 2017Sep; 5:197.

96. Goel M, Pankaj P, Agrawal A, Ashok C. Relationship of body mass index and other life style factors with hypertension in adolescents. Ann Pediatr Card. 2016; 9:29-34.

97. Kanciruk M, Andrews JW, Donnon T. Family history of obesity and risk of childhood overweight and obesity: A meta-analysis. International Journal of Psychological and Behavioural Sciences. 2014; 8(5).waset.org/abstracts/4316.

98. Poplawska K, Dudek K, Koziarz M, Cieniawski D, Drozdz T, Smiaek S, et al. Prematurity-Related Hypertension in Children and Adolescents. Int J Pediatr.2012; 2012:537936.

99. Bonamy AKE, Mohlkert LA, Hallberg J, Liuba P, Fellman V, Domellof M, et al. Blood Pressure in 6-Year-Old Children Born Extremely Preterm. J Am Heart Assoc. 2017; 6:e005858.

TITRE: PREVALENCE ET LES FACTEURS ASSOCIES DE L'HYPERTENSION ARTERIELLE CHEZ LES ELEVES DE L'ECOLE PRIMAIRE DANS L'ARRONDISSEMENT DE MBANKOMO

Numéro de Téléphone du tuteur légal:...................................................

6. Classe : [1] Sil/Class1[2] CP/ Class2[3]CE1/ Class3[4]CE2/ Class 4 [5]CM1/Class 5 [6]CM2/Class 6

9. Profession du tuteur légal : [1] Etudiant(e)/ élève [2]Secteur publique[3]Secteur privé [4] Secteur informel [5] Sans emploi [6] Autres...............................

10. Niveau d'éducation du tuteur légal :..........................................................

11. Profession du tuteur legal :.....................................................

1. Quel était son poids de naissance (en grammes) : ....................................

4. A-t-il(elle) déjà été diagnostiqué(e) d'une hypertension ? [1] Oui [2] Non

5. Si oui, où est-ce que le diagnostic a été fait? [1] A l'hôpital [2] Hors de l'hôpital.

7. Si oui, quel(s) est(sont) le(les) nom(s) de cette(s) médication(s)? [1] Benazepril [2] Fosinopril [3] Enalapril [4]Lisinopril [5] Irbesartan [6]Losartan [7] Propanolol [8] Amlodipine[9] Hydrochlorothiazide [10] Médicament traditionnel [11] Autre(s), précisez........................................

9. Si oui, chez lequel des membres? [1] Père [2] Mère [3] Grandparent[4] Oncle /tante [5] Frère /soeur

11. Si oui, chez lequel des membres? [1] Père [2] Mère [3] Grandparent[4] Oncle /tante [5] Frère /soeur

13. Si oui, chez lequel des membres? [1] Père [2] Mère [3] Grandparent[4] Oncle /tante [5] Frère /soeur

14. Quel était son poids de naissance (en grammes) : ....................................

17. A-t-il(elle) déjà été diagnostiqué(e) d'une hypertension ? [1] Oui [2] Non

18. Si oui, où est-ce que le diagnostic a été fait? [1] A l'hôpital [2] Hors de l'hôpital.

20. Si oui, quel(s) est(sont) le(les) nom(s) de cette(s) médication(s)? [1] Benazepril [2] Fosinopril [3] Enalapril [4]Lisinopril [5] Irbesartan [6]Losartan [7] Propanolol [8] Amlodipine[9] Hydrochlorothiazide [10] Médicament traditionnel [11] Autre(s), précisez........................................

22. Si oui, chez lequel des membres? [1] Père [2] Mère [3] Grandparent[4] Oncle /tante [5] Frère /soeur

24. Si oui, chez lequel des membres? [1] Père [2] Mère [3] Grandparent[4] Oncle /tante [5] Frère /soeur

26. Si oui, chez lequel des membres? [1] Père [2] Mère [3] Grandparent[4] Oncle /tante [5] Frère /soeur

27. Quel était son poids de naissance (en grammes) : ....................................

30. A-t-il(elle) déjà été diagnostiqué(e) d'une hypertension ? [1] Oui [2] Non

31. Si oui, où est-ce que le diagnostic a été fait? [1] A l'hôpital [2] Hors de l'hôpital.

33. Si oui, quel(s) est(sont) le(les) nom(s) de cette(s) médication(s)? [1] Benazepril [2] Fosinopril [3] Enalapril [4]Lisinopril [5] Irbesartan [6]Losartan [7] Propanolol [8] Amlodipine[9] Hydrochlorothiazide [10] Médicament traditionnel [11] Autre(s), précisez........................................

35. Si oui, chez lequel des membres? [1] Père [2] Mère [3] Grandparent[4] Oncle /tante [5] Frère /soeur

37. Si oui, chez lequel des membres? [1] Père [2] Mère [3] Grandparent[4] Oncle /tante [5] Frère /soeur

39. Si oui, chez lequel des membres? [1] Père [2] Mère [3] Grandparent[4] Oncle /tante [5] Frère /soeur

Revenue mensuel de la famille par mois (FCFA) : [1] =15.072[2] 15073 -45217 [3] 45.218 - 75.363 [4] 75.364-113.045 [5] 113.046-150.727 [6]150.728-301.454 [7] =301.455

13. Quel était son poids de naissance (en grammes) : ....................................

16. A-t-il(elle) déjà été diagnostiqué(e) d'une hypertension ? [1] Oui [2] Non

17. Si oui, où est-ce que le diagnostic a été fait? [1] A l'hôpital [2] Hors de l'hôpital.

19. Si oui, quel(s) est(sont) le(les) nom(s) de cette(s) médication(s)? [1] Benazepril [2] Fosinopril [3] Enalapril [4]Lisinopril [5] Irbesartan [6]Losartan [7] Propanolol [8] Amlodipine [9] Hydrochlorothiazide [10] Médicament traditionnel [11] Autre(s), précisez.....................................

21. Si oui, chez lequel des membres? [1] Père [2] Mère [3] Grandparent [4] Oncle /tante [5] Frère /soeur

23. Si oui, chez lequel des membres? [1] Père [2] Mère [3] Grandparent [4] Oncle /tante [5] Frère /soeur

25. Si oui, chez lequel des membres? [1] Père [2] Mère [3] Grandparent [4] Oncle /tante [5] Frère /soeur

28. Combien de fois consomme t-il/elleen moyenne des fruits par semaine: .....................

29. Combien de fois consomme t-il/elleen moyenne des légumes par semaine: ..................

30. Vous consommez des boissons gazeuses sucrées (jus brassés) ? [1] Occasionnellement [2] Régulièrement

31. Quelle quantité d'eaubuvez-vous en moyenne par jour? [1] Moins d'un demi-litre d'eau[2] Entre 0.5 litre et 1litre d'eau [3] Plus d'un litre d'eau

32. Principal moyen de locomotion pour aller à l'école: [1] A pieds [2] En vehicule

33. Si par vehicule, combien de temps de marche tu mets pour le prendre? ...............minutes

34. Si à pieds, combien de temps tu mets pour arriver à l'école? ...........................minutes

36. Si oui, combien d'heures en moyenne par semaine? ...................................heures.

38. Si oui, combien de fois par semaine? ..............................................

39. Combien d'heures par jour passes-tu devant la télévision ou les jeux ou l'ordinateur?

40. Temps de sommeil en heure par jour? [1] moins de 6 heures [2] 6-8 heures [3] Plus de 8 heures

43. Taille percentile ( à partir des courbes de référence)................................

45. IMC Percentile ( à partir des courbes de référence):[1] <5^eme[2] entre =5^eme et <85^eme [3] entre =85^eme et <95^eme[4] =95^eme

47. TAS percentile pour l'âge, le sexe et la taille : [1] < 90^eme[2] = 90^eme- <95^eme[3] = 95^eme - <99^eme[4] =99^eme +5mmHg

48. TAD percentile: [1] < 90^eme[2] = 90^eme- <95^eme[3] = 95^eme - <99^eme[4] =99^eme +5mmHg

50. TAS percentile pour l'âge, le sexe et la taille : [1] < 90^eme[2] = 90^eme- <95^eme[3] = 95^eme - <99^eme[4] =99^eme +5mmHg

51. TAD percentile: [1] < 90^eme[2] = 90^eme- <95^eme[3] = 95^eme - <99^eme[4] =99^eme +5mmHg

53. TAS percentile pour l'âge, le sexe et la taille : [1] < 90^eme[2] = 90^eme- <95^eme[3] = 95^eme - <99^eme[4] =99^eme +5mmHg

54. TAD percentile: [1] < 90^eme[2] = 90^eme- <95^eme[3] = 95^eme - <99^eme[4] =99^eme +5mmHg

55. Bandelette urinaire-Proteinurie :[1] Trace(<30mg/dl) [2] +1(=30-<100mg/dl) [3] +2(=100-<300mg/dl) [4] +3(=300 - <1000mg/dl) [5]+4(=1000mg/dl)

TITLE: PREVALENCE AND ASSOCIATED FACTORS OF HYPERTENSION IN PRIMARY SCHOOL CHILDREN IN THE MBANKOMO SUBDIVISION

Telephone number of legal tutor: ...................................................

6. Class: [1] Sil/Class1[2] CP/ Class2[3]CE1/ Class3[4]CE2/ Class 4 [5]CM1/Class 5 [6]CM2/Class 6

9. Legal tutor's Occupation: [1] Student [2] Public Sector [3] Private Sector [4] Informal sector [5] Unemployed [6] Other,precise........................................

10. Level of education of the legal tutor :....................................................

11. Profession of legal tutor :.............................................................

12. Monthly family income (FCFA) : [1] =15,072 [2] 15,073 - 45,217 [3] 45,218 - 75,363 [4] 75,364-113,045 [5] 113,046 - 150,727 [6]150,728 - 301,454 [7] =301,455

13. What was his birth weight (in grams): ....................................

17. If yes, where was the diagnosis made? [1] In the hospital [2] Out of the hospital.

19. If yes, which one (s) is (are) the name (s) of this medication (s)? [1] Benazepril [2] Fosinopril [3] Enalapril [4] Lisinopril [5] Irbesartan [6] Losartan [7] Propanolol [8] Amlodipine [9] Hydrochlorothiazide [10] Traditional medicine [11] Other (s), please specify ........................................

21. If yes, which members? [1] Father [2] Mother [3] Grandparent [4] Uncle / aunt [5] Brother / sister

23. If yes, which members? [1] Father [2] Mother [3] Grandparent [4] Uncle / aunt [5] Brother / sister

25. ??If yes, which members? [1] Father [2] Mother [3] Grandparent [4] Uncle / aunt [5] Brother / sister

28. How many times does he / she eat fruit on average per week: ..............................................

29. How many times does he / she consume vegetables on average per week: ............................

30. Do you eat sweetened soft drinks (brewed juice)? [1] Occasionally [2] Regularly

31. What quantity of water do you drink on average per day? [1] Less than half a liter of water [2] Between 0.5 liter and 1 liter of water [3] More than one liter of water.

33. If by vehicle, how long do you take to take it? .....................minutes

34. If on foot, how long do you take to get to school? ..............................minutes

36. If yes, how many hours on average per week? ................................... hours.

38. If yes, how many times a week? ..............................................

39. How many hours a day do you spend watching television and/or games and/or computer?[1] Less than an hour [2] 1-2 hours [3] More than 2 hours

40. Sleep time in hours per day? [1] less than 6 hours [2] 6-8 hours [3] More than 8 hours

43. Height Percentile (from the reference curves) ................................

44. BMI (Calculated): ................................................ .kg / m²

45. BMI Percentile (from the reference curves): [1] <5^th [2] between =5^th and <85^th[3] between =85^thand <95^th[4] =95^th

46. Blood pressure: SBP ............................... DBP................................... ....

47. SBP percentile for age, sex and height: [1] <90^th [2] = 90^th - <95^th[3] = 95^th - <99^th[4] =99^th + 5mmHg

48. DBP Percentile : [1] <90^th[2] = 90^th - <95^th[3] = 95^th - <99^th[4] =99^th + 5mmHg

49. Blood pressure: SBP ............................... DBP................................... ....

50. SBP percentile for age, sex and height: [1] <90^th [2] = 90^th - <95^th[3] = 95^th - <99^th[4] =99^th + 5mmHg

51. DBP Percentile : [1] <90^th[2] = 90^th - <95^th[3] = 95^th - <99^th[4] =99^th + 5mmHg

52. Blood pressure: SBP ............................... DBP................................... ....

53. SBP percentile for age, sex and height: [1] <90^th [2] = 90^th - <95^th[3] = 95^th - <99^th[4] =99^th + 5mmHg

54. DBP Percentile : [1] <90^th[2] = 90^th - <95^th[3] = 95^th - <99^th[4] =99^th + 5mmHg

55. Urine dipstick-Proteinuria: [1] Trace (<30mg / dl) [2] +1 (=30 - <100mg / dl) [3] +2 (=100- <300mg / dl) [4] +3 (=300 - <1000mg / dl) [5] +4 (=1000mg / dl)

I am CHIABI EDMOND NGONG,a 7^th year medical student of the Faculty of Medicine and Biomedical Sciences of the University of Yaounde I. I am carrying out a study titled «Prevalence and associated Factorsof Hypertension in Primary School Children in theMbankomo subdivision, Centre Region of Cameroon.»

The main aim of this study is to generate data and increase awareness on High blood pressure in children in the rural environment.

You are kindly invited to enroll your child in this study. We would like you to know that the participation of your child in this study is strictly voluntary. If you decide not enroll your child in this study, your decision will be respected without further questioning. If along the course of the study you decide not to participate any further, you are free to withdraw your child from the studywithout pre- notification, such a decision will be respected without any further questioning.

During the process, you will be sent a questionnaire to be filled. The investigator will also examine your child by taking his/her blood pressure, the weight,the height and the collected urine. NO BLOOD will be collected throughout the study and NO INVASIVE TESTwill be done.

The study is almost free from risk apart from the fact that a few minutes will be taken off your child's study period to conduct the study.

Your child will NOT BE PAID for participating in this study. However he / she might benefit from early diagnosis of childhood and adolescent hypertension and referral to the doctor for follow up.

This will be ensured by not collecting your child's name and other sensitive information. By keeping filled questionnaires in a save where only the investigators have access. The information will be entered into a computer software using codes.

Please if you have any doubts concerning this study; feel free to ask the investigator. Questions can also be directed to the supervisors using the addresses below:

I.................................................................................... having understood the study, after having the study/consent form thoroughly explained to me, having been given the opportunity to ask questions and time to consider my participation in the study, I do hereby agree to enroll my child to participate in this study.

Je me nomme CHIABI Edmond NGONG, étudiant en 7^e année de Médecine Générale à la Faculté de Médecine et des Sciences Biomédicales de l'Université de Yaoundé I (ex CUSS). Je sollicite votre participation ainsi que celle de votre enfant à l'étude intitulée : ·Prévalence et les facteurs associés de l'hypertension artérielle chez les enfants de l'école primaire dans l'arrondissement de Mbankomo·.

Le but de cette étude est de connaître le niveau de tension artérielle de base de l'enfant « sain » afin de déterminer la prévalence et les facteurs de risque de l'hypertension artérielle en milieu scolaire dans un milieu rural.

Si vous acceptez de participer à cette étude (vous et votre enfant), vous répondrez au questionnaire qui vous est adressé ; et l'investigateuràl'école, examinera l'enfant par la prise de sa tension artérielle, son poids, sa taille et l'urine collectée. Aucune prise de sang sera faite ni autre examen invasif.

Nous ne prévoyons pas de risques, des effets secondaires ou inconvénients quant à la participation à cette étude. Aucun revenu financier n'est engagé en participant à l'étude.

La confidentialité et l'Éthique
Toutes les informations recueillies dans le cadre de cette étude seront anonymes et confidentielles. L'étude sera effectuée selon les principes et directives nationales et internationales applicables en matière d'Éthique.

Pour plus ample information vous pourrez directement nous contacter personnellement au :

(Renvoyez nous ce consentement après signature et le questionnaire dûment remplis)

Je soussigné Mme /Mr ................................................................. ..................................................................................................

Parent de l'enfant ....................................................... Atteste avoir reçu toutes les informations relatives à l'étude : « Prévalence et les facteurs associés de l'hypertension artérielle chez les enfants de l'école primaire dans l'arrondissement de Mbankomo »

J'accepte librement de participer à l'étude ainsi que mon enfant, en répondant à toutes les questions qui me seront posées et en soumettant mon enfant à la réalisation de la procédure de l'étude qui m'a été clairement expliquée.

J'ai lu cette fiche de consentement éclairée et en ai reçu une copie ; je ne demande aucune rémunération aux investigateurs de ce travail.

J'ai compris le but de l'étude, ses avantages sur la prise en charge et la prévention de l'hypertension artérielle en milieu scolaire ; j'accepte que les données recueillies puissent être exploitées pour la recherche scientifique.

Age (y)	BP Percentile	SBP (mm?Hg)							DBP (mm?Hg)
		Height Percentile or Measured Height							Height Percentile or Measured Height
		5%	10%	25%	50%	75%	90%	95%	5%	10%	25%	50%	75%	90%	95%
1	Height (in)	30.4	30.8	31.6	32.4	33.3	34.1	34.6	30.4	30.8	31.6	32.4	33.3	34.1	34.6
	Height (cm)	77.2	78.3	80.2	82.4	84.6	86.7	87.9	77.2	78.3	80.2	82.4	84.6	86.7	87.9
	50^th	85	85	86	86	87	88	88	40	40	40	41	41	42	42
	90^th	98	99	99	100	100	101	101	52	52	53	53	54	54	54
	95^th	102	102	103	103	104	105	105	54	54	55	55	56	57	57
	95th + 12 mm?Hg	114	114	115	115	116	117	117	66	66	67	67	68	69	69
2	Height (in)	33.9	34.4	35.3	36.3	37.3	38.2	38.8	33.9	34.4	35.3	36.3	37.3	38.2	38.8
	Height (cm)	86.1	87.4	89.6	92.1	94.7	97.1	98.5	86.1	87.4	89.6	92.1	94.7	97.1	98.5
	50^th	87	87	88	89	89	90	91	43	43	44	44	45	46	46
	90^th	100	100	101	102	103	103	104	55	55	56	56	57	58	58
	95^th	104	105	105	106	107	107	108	57	58	58	59	60	61	61
	95th + 12 mm?Hg	116	117	117	118	119	119	120	69	70	70	71	72	73	73
3	Height (in)	36.4	37	37.9	39	40.1	41.1	41.7	36.4	37	37.9	39	40.1	41.1	41.7
	Height (cm)	92.5	93.9	96.3	99	101.8	104.3	105.8	92.5	93.9	96.3	99	101.8	104.3	105.8
	50th	88	89	89	90	91	92	92	45	46	46	47	48	49	49
	90th	101	102	102	103	104	105	105	58	58	59	59	60	61	61
	95th	106	106	107	107	108	109	109	60	61	61	62	63	64	64
	95th + 12 mm?Hg	118	118	119	119	120	121	121	72	73	73	74	75	76	76
4	Height (in)	38.8	39.4	40.5	41.7	42.9	43.9	44.5	38.8	39.4	40.5	41.7	42.9	43.9	44.5
	Height (cm)	98.5	100.2	102.9	105.9	108.9	111.5	113.2	98.5	100.2	102.9	105.9	108.9	111.5	113.2
	50th	90	90	91	92	93	94	94	48	49	49	50	51	52	52
	90th	102	103	104	105	105	106	107	60	61	62	62	63	64	64
	95th	107	107	108	108	109	110	110	63	64	65	66	67	67	68
	95th + 12 mm?Hg	119	119	120	120	121	122	122	75	76	77	78	79	79	80
5	Height (in)	41.1	41.8	43.0	44.3	45.5	46.7	47.4	41.1	41.8	43.0	44.3	45.5	46.7	47.4
	Height (cm)	104.4	106.2	109.1	112.4	115.7	118.6	120.3	104.4	106.2	109.1	112.4	115.7	118.6	120.3
	50th	91	92	93	94	95	96	96	51	51	52	53	54	55	55
	90th	103	104	105	106	107	108	108	63	64	65	65	66	67	67
	95th	107	108	109	109	110	111	112	66	67	68	69	70	70	71
	95th + 12 mm?Hg	119	120	121	121	122	123	124	78	79	80	81	82	82	83
6	Height (in)	43.4	44.2	45.4	46.8	48.2	49.4	50.2	43.4	44.2	45.4	46.8	48.2	49.4	50.2
	Height (cm)	110.3	112.2	115.3	118.9	122.4	125.6	127.5	110.3	112.2	115.3	118.9	122.4	125.6	127.5
	50th	93	93	94	95	96	97	98	54	54	55	56	57	57	58
	90th	105	105	106	107	109	110	110	66	66	67	68	68	69	69
	95th	108	109	110	111	112	113	114	69	70	70	71	72	72	73
	95th + 12 mm?Hg	120	121	122	123	124	125	126	81	82	82	83	84	84	85
7	Height (in)	45.7	46.5	47.8	49.3	50.8	52.1	52.9	45.7	46.5	47.8	49.3	50.8	52.1	52.9
	Height (cm)	116.1	118	121.4	125.1	128.9	132.4	134.5	116.1	118	121.4	125.1	128.9	132.4	134.5
	50th	94	94	95	97	98	98	99	56	56	57	58	58	59	59
	90th	106	107	108	109	110	111	111	68	68	69	70	70	71	71
	95th	110	110	111	112	114	115	116	71	71	72	73	73	74	74
	95th + 12 mm?Hg	122	122	123	124	126	127	128	83	83	84	85	85	86	86
8	Height (in)	47.8	48.6	50	51.6	53.2	54.6	55.5	47.8	48.6	50	51.6	53.2	54.6	55.5
	Height (cm)	121.4	123.5	127	131	135.1	138.8	141	121.4	123.5	127	131	135.1	138.8	141
	50th	95	96	97	98	99	99	100	57	57	58	59	59	60	60
	90th	107	108	109	110	111	112	112	69	70	70	71	72	72	73
	95th	111	112	112	114	115	116	117	72	73	73	74	75	75	75
	95th + 12 mm?Hg	123	124	124	126	127	128	129	84	85	85	86	87	87	87
9	Height (in)	49.6	50.5	52	53.7	55.4	56.9	57.9	49.6	50.5	52	53.7	55.4	56.9	57.9
	Height (cm)	126	128.3	132.1	136.3	140.7	144.7	147.1	126	128.3	132.1	136.3	140.7	144.7	147.1
	50th	96	97	98	99	100	101	101	57	58	59	60	61	62	62
	90th	107	108	109	110	112	113	114	70	71	72	73	74	74	74
	95th	112	112	113	115	116	118	119	74	74	75	76	76	77	77
	95th + 12 mm?Hg	124	124	125	127	128	130	131	86	86	87	88	88	89	89
10	Height (in)	51.3	52.2	53.8	55.6	57.4	59.1	60.1	51.3	52.2	53.8	55.6	57.4	59.1	60.1
	Height (cm)	130.2	132.7	136.7	141.3	145.9	150.1	152.7	130.2	132.7	136.7	141.3	145.9	150.1	152.7
	50th	97	98	99	100	101	102	103	59	60	61	62	63	63	64
	90th	108	109	111	112	113	115	116	72	73	74	74	75	75	76
	95th	112	113	114	116	118	120	121	76	76	77	77	78	78	78
	95th + 12 mm?Hg	124	125	126	128	130	132	133	88	88	89	89	90	90	90
11	Height (in)	53	54	55.7	57.6	59.6	61.3	62.4	53	54	55.7	57.6	59.6	61.3	62.4
	Height (cm)	134.7	137.3	141.5	146.4	151.3	155.8	158.6	134.7	137.3	141.5	146.4	151.3	155.8	158.6
	50th	99	99	101	102	103	104	106	61	61	62	63	63	63	63
	90th	110	111	112	114	116	117	118	74	74	75	75	75	76	76
	95th	114	114	116	118	120	123	124	77	78	78	78	78	78	78
	95th + 12 mm?Hg	126	126	128	130	132	135	136	89	90	90	90	90	90	90
12	Height (in)	55.2	56.3	58.1	60.1	62.2	64	65.2	55.2	56.3	58.1	60.1	62.2	64	65.2
	Height (cm)	140.3	143	147.5	152.7	157.9	162.6	165.5	140.3	143	147.5	152.7	157.9	162.6	165.5
	50th	101	101	102	104	106	108	109	61	62	62	62	62	63	63
	90th	113	114	115	117	119	121	122	75	75	75	75	75	76	76
	95th	116	117	118	121	124	126	128	78	78	78	78	78	79	79
	95th + 12 mm?Hg	128	129	130	133	136	138	140	90	90	90	90	90	91	91
13	Height (in)	57.9	59.1	61	63.1	65.2	67.1	68.3	57.9	59.1	61	63.1	65.2	67.1	68.3
	Height (cm)	147	150	154.9	160.3	165.7	170.5	173.4	147	150	154.9	160.3	165.7	170.5	173.4
	50th	103	104	105	108	110	111	112	61	60	61	62	63	64	65
	90th	115	116	118	121	124	126	126	74	74	74	75	76	77	77
	95th	119	120	122	125	128	130	131	78	78	78	78	80	81	81
	95th and 12 mm?Hg	131	132	134	137	140	142	143	90	90	90	90	92	93	93
14	Height (in)	60.6	61.8	63.8	65.9	68.0	69.8	70.9	60.6	61.8	63.8	65.9	68.0	69.8	70.9
	Height (cm)	153.8	156.9	162	167.5	172.7	177.4	180.1	153.8	156.9	162	167.5	172.7	177.4	180.1
	50th	105	106	109	111	112	113	113	60	60	62	64	65	66	67
	90th	119	120	123	126	127	128	129	74	74	75	77	78	79	80
	95th	123	125	127	130	132	133	134	77	78	79	81	82	83	84
	95th and 12 mm?Hg	135	137	139	142	144	145	146	89	90	91	93	94	95	96
15	Height (in)	62.6	63.8	65.7	67.8	69.8	71.5	72.5	62.6	63.8	65.7	67.8	69.8	71.5	72.5
	Height (cm)	159	162	166.9	172.2	177.2	181.6	184.2	159	162	166.9	172.2	177.2	181.6	184.2
	50th	108	110	112	113	114	114	114	61	62	64	65	66	67	68
	90th	123	124	126	128	129	130	130	75	76	78	79	80	81	81
	95th	127	129	131	132	134	135	135	78	79	81	83	84	85	85
	95th and 12 mm?Hg	139	141	143	144	146	147	147	90	91	93	95	96	97	97
16	Height (in)	63.8	64.9	66.8	68.8	70.7	72.4	73.4	63.8	64.9	66.8	68.8	70.7	72.4	73.4
	Height (cm)	162.1	165	169.6	174.6	179.5	183.8	186.4	162.1	165	169.6	174.6	179.5	183.8	186.4
	50th	111	112	114	115	115	116	116	63	64	66	67	68	69	69
	90th	126	127	128	129	131	131	132	77	78	79	80	81	82	82
	95th	130	131	133	134	135	136	137	80	81	83	84	85	86	86
	95th and 12 mm?Hg	142	143	145	146	147	148	149	92	93	95	96	97	98	98
17	Height (in)	64.5	65.5	67.3	69.2	71.1	72.8	73.8	64.5	65.5	67.3	69.2	71.1	72.8	73.8
	Height (cm)	163.8	166.5	170.9	175.8	180.7	184.9	187.5	163.8	166.5	170.9	175.8	180.7	184.9	187.5
	50th	114	115	116	117	117	118	118	65	66	67	68	69	70	70
	90th	128	129	130	131	132	133	134	78	79	80	81	82	82	83
	95th	132	133	134	135	137	138	138	81	82	84	85	86	86	87
	95th and 12 mm?Hg	144	145	146	147	149	150	150	93	94	96	97	98	98	99

Age (y)	BP Percentile	SBP (mm?Hg)							DBP (mm?Hg)
		Height Percentile or Measured Height							Height Percentile or Measured Height
		5%	10%	25%	50%	75%	90%	95%	5%	10%	25%	50%	75%	90%	95%
1	Height (in)	29.7	30.2	30.9	31.8	32.7	33.4	33.9	29.7	30.2	30.9	31.8	32.7	33.4	33.9
	Height (cm)	75.4	76.6	78.6	80.8	83	84.9	86.1	75.4	76.6	78.6	80.8	83	84.9	86.1
	50th	84	85	86	86	87	88	88	41	42	42	43	44	45	46
	90th	98	99	99	100	101	102	102	54	55	56	56	57	58	58
	95th	101	102	102	103	104	105	105	59	59	60	60	61	62	62
	95th + 12 mm?Hg	113	114	114	115	116	117	117	71	71	72	72	73	74	74
2	Height (in)	33.4	34	34.9	35.9	36.9	37.8	38.4	33.4	34	34.9	35.9	36.9	37.8	38.4
	Height (cm)	84.9	86.3	88.6	91.1	93.7	96	97.4	84.9	86.3	88.6	91.1	93.7	96	97.4
	50th	87	87	88	89	90	91	91	45	46	47	48	49	50	51
	90th	101	101	102	103	104	105	106	58	58	59	60	61	62	62
	95th	104	105	106	106	107	108	109	62	63	63	64	65	66	66
	95th + 12 mm?Hg	116	117	118	118	119	120	121	74	75	75	76	77	78	78
3	Height (in)	35.8	36.4	37.3	38.4	39.6	40.6	41.2	35.8	36.4	37.3	38.4	39.6	40.6	41.2
	Height (cm)	91	92.4	94.9	97.6	100.5	103.1	104.6	91	92.4	94.9	97.6	100.5	103.1	104.6
	50th	88	89	89	90	91	92	93	48	48	49	50	51	53	53
	90th	102	103	104	104	105	106	107	60	61	61	62	63	64	65
	95th	106	106	107	108	109	110	110	64	65	65	66	67	68	69
	95th + 12 mm?Hg	118	118	119	120	121	122	122	76	77	77	78	79	80	81
4	Height (in)	38.3	38.9	39.9	41.1	42.4	43.5	44.2	38.3	38.9	39.9	41.1	42.4	43.5	44.2
	Height (cm)	97.2	98.8	101.4	104.5	107.6	110.5	112.2	97.2	98.8	101.4	104.5	107.6	110.5	112.2
	50th	89	90	91	92	93	94	94	50	51	51	53	54	55	55
	90th	103	104	105	106	107	108	108	62	63	64	65	66	67	67
	95th	107	108	109	109	110	111	112	66	67	68	69	70	70	71
	95th + 12 mm?Hg	119	120	121	121	122	123	124	78	79	80	81	82	82	83
5	Height (in)	40.8	41.5	42.6	43.9	45.2	46.5	47.3	40.8	41.5	42.6	43.9	45.2	46.5	47.3
	Height (cm)	103.6	105.3	108.2	111.5	114.9	118.1	120	103.6	105.3	108.2	111.5	114.9	118.1	120
	50th	90	91	92	93	94	95	96	52	52	53	55	56	57	57
	90th	104	105	106	107	108	109	110	64	65	66	67	68	69	70
	95th	108	109	109	110	111	112	113	68	69	70	71	72	73	73
	95th + 12 mm?Hg	120	121	121	122	123	124	125	80	81	82	83	84	85	85
6	Height (in)	43.3	44	45.2	46.6	48.1	49.4	50.3	43.3	44	45.2	46.6	48.1	49.4	50.3
	Height (cm)	110	111.8	114.9	118.4	122.1	125.6	127.7	110	111.8	114.9	118.4	122.1	125.6	127.7
	50th	92	92	93	94	96	97	97	54	54	55	56	57	58	59
	90th	105	106	107	108	109	110	111	67	67	68	69	70	71	71
	95th	109	109	110	111	112	113	114	70	71	72	72	73	74	74
	95th + 12 mm?Hg	121	121	122	123	124	125	126	82	83	84	84	85	86	86
7	Height (in)	45.6	46.4	47.7	49.2	50.7	52.1	53	45.6	46.4	47.7	49.2	50.7	52.1	53
	Height (cm)	115.9	117.8	121.1	124.9	128.8	132.5	134.7	115.9	117.8	121.1	124.9	128.8	132.5	134.7
	50th	92	93	94	95	97	98	99	55	55	56	57	58	59	60
	90th	106	106	107	109	110	111	112	68	68	69	70	71	72	72
	95th	109	110	111	112	113	114	115	72	72	73	73	74	74	75
	95th + 12 mm?Hg	121	122	123	124	125	126	127	84	84	85	85	86	86	87
8	Height (in)	47.6	48.4	49.8	51.4	53	54.5	55.5	47.6	48.4	49.8	51.4	53	54.5	55.5
	Height (cm)	121	123	126.5	130.6	134.7	138.5	140.9	121	123	126.5	130.6	134.7	138.5	140.9
	50th	93	94	95	97	98	99	100	56	56	57	59	60	61	61
	90th	107	107	108	110	111	112	113	69	70	71	72	72	73	73
	95th	110	111	112	113	115	116	117	72	73	74	74	75	75	75
	95th + 12 mm?Hg	122	123	124	125	127	128	129	84	85	86	86	87	87	87
9	Height (in)	49.3	50.2	51.7	53.4	55.1	56.7	57.7	49.3	50.2	51.7	53.4	55.1	56.7	57.7
	Height (cm)	125.3	127.6	131.3	135.6	140.1	144.1	146.6	125.3	127.6	131.3	135.6	140.1	144.1	146.6
	50th	95	95	97	98	99	100	101	57	58	59	60	60	61	61
	90th	108	108	109	111	112	113	114	71	71	72	73	73	73	73
	95th	112	112	113	114	116	117	118	74	74	75	75	75	75	75
	95th + 12 mm?Hg	124	124	125	126	128	129	130	86	86	87	87	87	87	87
10	Height (in)	51.1	52	53.7	55.5	57.4	59.1	60.2	51.1	52	53.7	55.5	57.4	59.1	60.2
	Height (cm)	129.7	132.2	136.3	141	145.8	150.2	152.8	129.7	132.2	136.3	141	145.8	150.2	152.8
	50th	96	97	98	99	101	102	103	58	59	59	60	61	61	62
	90th	109	110	111	112	113	115	116	72	73	73	73	73	73	73
	95th	113	114	114	116	117	119	120	75	75	76	76	76	76	76
	95th + 12 mm?Hg	125	126	126	128	129	131	132	87	87	88	88	88	88	88
11	Height (in)	53.4	54.5	56.2	58.2	60.2	61.9	63	53.4	54.5	56.2	58.2	60.2	61.9	63
	Height (cm)	135.6	138.3	142.8	147.8	152.8	157.3	160	135.6	138.3	142.8	147.8	152.8	157.3	160
	50th	98	99	101	102	104	105	106	60	60	60	61	62	63	64
	90th	111	112	113	114	116	118	120	74	74	74	74	74	75	75
	95th	115	116	117	118	120	123	124	76	77	77	77	77	77	77
	95th + 12 mm?Hg	127	128	129	130	132	135	136	88	89	89	89	89	89	89
12	Height (in)	56.2	57.3	59	60.9	62.8	64.5	65.5	56.2	57.3	59	60.9	62.8	64.5	65.5
	Height (cm)	142.8	145.5	149.9	154.8	159.6	163.8	166.4	142.8	145.5	149.9	154.8	159.6	163.8	166.4
	50th	102	102	104	105	107	108	108	61	61	61	62	64	65	65
	90th	114	115	116	118	120	122	122	75	75	75	75	76	76	76
	95th	118	119	120	122	124	125	126	78	78	78	78	79	79	79
	95th and 12 mm?Hg	130	131	132	134	136	137	138	90	90	90	90	91	91	91
13	Height (in)	58.3	59.3	60.9	62.7	64.5	66.1	67	58.3	59.3	60.9	62.7	64.5	66.1	67
	Height (cm)	148.1	150.6	154.7	159.2	163.7	167.8	170.2	148.1	150.6	154.7	159.2	163.7	167.8	170.2
	50th	104	105	106	107	108	108	109	62	62	63	64	65	65	66
	90th	116	117	119	121	122	123	123	75	75	75	76	76	76	76
	95th	121	122	123	124	126	126	127	79	79	79	79	80	80	81
	95th + 12 mm?Hg	133	134	135	136	138	138	139	91	91	91	91	92	92	93
14	Height (in)	59.3	60.2	61.8	63.5	65.2	66.8	67.7	59.3	60.2	61.8	63.5	65.2	66.8	67.7
	Height (cm)	150.6	153	156.9	161.3	165.7	169.7	172.1	150.6	153	156.9	161.3	165.7	169.7	172.1
	50th	105	106	107	108	109	109	109	63	63	64	65	66	66	66
	90th	118	118	120	122	123	123	123	76	76	76	76	77	77	77
	95th	123	123	124	125	126	127	127	80	80	80	80	81	81	82
	95th + 12 mm?Hg	135	135	136	137	138	139	139	92	92	92	92	93	93	94
15	Height (in)	59.7	60.6	62.2	63.9	65.6	67.2	68.1	59.7	60.6	62.2	63.9	65.6	67.2	68.1
	Height (cm)	151.7	154	157.9	162.3	166.7	170.6	173	151.7	154	157.9	162.3	166.7	170.6	173
	50th	105	106	107	108	109	109	109	64	64	64	65	66	67	67
	90th	118	119	121	122	123	123	124	76	76	76	77	77	78	78
	95th	124	124	125	126	127	127	128	80	80	80	81	82	82	82
	95th + 12 mm?Hg	136	136	137	138	139	139	140	92	92	92	93	94	94	94
16	Height (in)	59.9	60.8	62.4	64.1	65.8	67.3	68.3	59.9	60.8	62.4	64.1	65.8	67.3	68.3
	Height (cm)	152.1	154.5	158.4	162.8	167.1	171.1	173.4	152.1	154.5	158.4	162.8	167.1	171.1	173.4
	50th	106	107	108	109	109	110	110	64	64	65	66	66	67	67
	90th	119	120	122	123	124	124	124	76	76	76	77	78	78	78
	95th	124	125	125	127	127	128	128	80	80	80	81	82	82	82
	95th + 12 mm?Hg	136	137	137	139	139	140	140	92	92	92	93	94	94	94
17	Height (in)	60.0	60.9	62.5	64.2	65.9	67.4	68.4	60.0	60.9	62.5	64.2	65.9	67.4	68.4
	Height (cm)	152.4	154.7	158.7	163.0	167.4	171.3	173.7	152.4	154.7	158.7	163.0	167.4	171.3	173.7
	50th	107	108	109	110	110	110	111	64	64	65	66	66	66	67
	90th	120	121	123	124	124	125	125	76	76	77	77	78	78	78
	95th	125	125	126	127	128	128	128	80	80	80	81	82	82	82
	95th + 12 mm?Hg	137	137	138	139	140	140	140	92	92	92	93	94	94	94

· History of prematurity, very low birth weight, or other neonatal complication requiring intensive care

· Other systemic illnesses associated with hypertension (neurofibromatosis, tuberous sclerosis, etc.)

Table II: Antihypertensive medications with FDA approval for use in children

Table III: Oral and Intravenous Antihypertensive Medications for Acute Severe HTN

Prevalence and associated factors of hypertension in primary school children in mbankomo subdivision in the mefou and akono division, centre region

CHAPTER II: JUSTIFICATION OF STUDY

CHAPTER III: RESEARCH QUESTION

CHAPTER IV: RESEARCH HYPOTHESIS

CHAPTER V: OBJECTIVES