Association of systolic blood pressure with body weight and the metabolic syundrome in children

Abstract

INTRODUCTION: Our previous study in British schoolboys suggested a strong relationship between systolic blood pressure (SBP) and obesity. To characterize this relationship further, we analyzed the latest United States National Health and Nutrition Examination Survey (NHANES) data. METHODS: 1981 participants (1007 boys, 974 girls) of NHANES 2011-2 age <20 (mean age 13.0±3.5 yrs) were included in the analysis. The National Center for Health Statistics Research Ethics Review Board approved the protocol. Certified personnel measured blood pressure. Central laboratories analyzed the blood samples. Lifestyle information was obtained using questionnaires. RESULTS: SBP and diastolic blood pressure (DBP) correlated with body weight (BW) (r=0.51 and 0.28 respectively, p<0.001) more strongly than with BMI or waist circumference. SBP correlated more strongly with BW in boys than girls (r=0.57 and 0.38 respectively, p<0.001; age-adjusted r=0.34 and 0.26 respectively, p<0.001). In boys, SBP also correlated with serum insulin, HDL and triglycerides (r=0.22, 0.22 and 0.32 respectively, p<0.001), but these correlations became insignificant when adjusted for BW. There was no significant association between SBP or DBP with smoking, alcohol intake, quantity or quality of sleep, hours of television viewing, hours at computer, or amount or rigor of physical exercise. In a general linear model, BW, age and gender explained 30% (35% in boys and 16% in girls) of the variance in SBP. CONCLUSIONS: Increased SBP in children is strongly related to BW; in boys, it is also associated with components of the metabolic syndrome. Our results emphasize the importance of children's eating habits.