Elevated Blood Pressure Among Zimbabwean Urban Primary School Children Aged 5–11 Years

Abstract

Following few publications available with data on blood pressure profiles of Zimbabwean population, especially children and adolescents, few data exist on urban and rural school going children. The aims of this study were to examine the incidence of hypertension (HT) among Zimbabwean urban children residing in Kwekwe; and to determine the relationship between body mass index (BMI) and blood pressure (BP) among them. The study involved 480 primary school children (230 boys and 250 girls) aged 5–11 years. Stature and body weight were measured using standard procedures. BMI for gender and age defined overweight. BP was monitored for thrice consecutively using validated electronic devices (Omron 7051T). HT was determined as the average of three separate BP readings where the systolic or diastolic blood pressure was ≥ 95th percentile for age and sex. The incidence of overweight among the girls (3.6%) was higher compared with the boys (2.7%). Both systolic and diastolic pressures (SBP and DBP) increase with age in both sexes. Potential development of hypertension among the children is noticeable at Early Childhood Development (ECD) level for both boys and girls; 1.8% and 1.5% respectively and ranged from 0.8% to 1.8% for boys and 2.0% to 5.3% for girls. The overall incidence of hypertension was 1.5% and 2.6% in boys and girls, respectively. The highest noticeable value for boys was at ECD and decreased with increase in grade level. The incidence of hypertension (SBP > 95th percentile) was 0.4% and 0.2% in boys and girls, respectively. For the girls there was a progressive increase in the tendency towards development of hypertension from ECD to 6 th grade except a small decrease in 3 rd and 4 th grade levels. Girls in the 6 th grade level showed the highest value of incidence of hypertension (5.3%). The blood pressures (SBP and DBP) significantly correlated with age, stature, body mass and BMI (P<0.05). The findings demonstrate that elevated blood pressure is prevalent among urban Zimbabwean children and that there is need for routine measurement of BP to children residing in this region as part of physical examination for physical activity in schools. The use of BMI cutoffs tailored to metabolic risks may be vital for assessment of overweight. BP increased with age in both sexes, and this significantly correlated with age, stature, body weight and BMI.