The relationship between basal blood pressure and body mass index in apparently healthy Nigerian adolescent students

Background: In contrast to the situation in developed countries, very few studies have been done on blood pressure (BP) determinants among Nigerian adolescents. Aim: To evaluate the relationship between basal BP and body mass index (BMI) in a group of healthy Nigerian secondary school students. Methods: This was a cross-sectional study of 1080 adolescent students selected by a two-stage multi-phase cluster sampling technique. The height, weight and BP of each student were taken using standard methods. Pearson correlation was used to describe the strength of association between variables. Multiple stepwise regressions were conducted to determine the individual or combined contribution(s) of some variables to the variation in BP levels. Results: Mean BMI for males and females were 17.63 ± 2.54 kg/m2 and 18.87 ± 1.81 kg/m2 respectively. Forty six students (4.3%) were overweight. Mean systolic and diastolic BPs were 113.13 + 11.44 mm Hg and 68.29 + 8.07 mm Hg respectively. Thirty-five subjects (3.2%) had systolic or diastolic BP above the 95th percentile for age and sex. Twenty-four (68.6%) of these subjects were also found to be overweight. A moderate positive correlation was observed between both systolic and diastolic BP and BMI. Regression analysis showed that weight, height and BMI were predictors of systolic BP. Height and BMI were the only predictors of diastolic BP. Conclusion: These findings suggest that there is a moderate association between basal BP and BMI. Recommendation: Control/prevention of the accumulation of excess body fat in adolescence is recommended.