Background: Hypertension is defined as average systolic and/or diastolic blood pressure (BP) ≥95th per centile for gender, age and height, and pre-hypertension as ≥90th and <95th per centile, measured on three occasions. Although the prevalence of hypertension during childhood is lower than that in adulthood, it is not rare in children.
Aims and objectives: To evaluate the prevalence of hypertension and its severity in primary school-children in Port Harcourt.
Methods: A stratified, multi-staged sampling technique was used to recruit pupils between 6 and 12 years of age in 13 primary schools. Data were collected using a pre-tested questionnaire completed by parents/guardians. The average of three blood pressure measurements was taken for each pupil using standardized techniques.
Results: A total of 1302 pupils of whom 585 (44·9%) males and 717 (55·1%) females were studied, giving a male to female ratio of 1:1·2. The prevalence of hypertension was 61 (4·7%), 55 (4·2%) with stage 1 and six (0·5%) with stage 2 hypertension. Sixty (4·6%) of the pupils had pre-hypertension. Twenty-three (3·9%) of the 585 males and 38 (5·3%) of the 717 females were hypertensive (P = 0·25). The mean (SD) age of 8·83 (1·90) years for the normotensive children was higher than the mean (SD) age of 8·56 (2·05) years for the hypertensive children (P = 0·27). Of the study subjects, 152 (11·7%) were underweight, 998 (76·7%) were of normal weight, 75 (5·7%) were overweight and 77 (5·9%) were obese. The prevalence of hypertension among the different weight groups fell steadily from 13 (16·9%) in the obese children to 4 (5·3%) in the overweight children, to 43 (4·3%) in the normal weight children and one (0·7%) in the underweight children (P<0·001).
Conclusion: The prevalence of hypertension in school-children in Port Harcourt is 4·7% which is similar to that in other studies in Nigeria and elsewhere. A higher BMI was significantly associated with a higher prevalence of hypertension.