Body mass index, waist circumference, body fat mass, and risk of developing hypertension in normal-weight children and adolescents

Background and aims: We prospectively examined the association between three adiposity indices, including body mass index (BMI), waist circumference (WC), and percentage of body fat (PBF), and risk of hypertension in normal-weight Chinese children. Methods and results: The current study included 1526 (713 boys and 813 girls) normal-weight Chinese children (age 6-14 years old), who were free of hypertension at baseline (2014). Heights, body weight, WC, and PBF (estimated by bioelectrical impedance analysis) were measured at the baseline. Blood pressure was repeatedly measured in 2014, 2015 and 2016. Hypertension was defined as either high systolic blood pressure and/or high diastolic blood pressure, according to age-and sex-specific 95th percentile for Chinese children. We used Cox proportional hazards model to calculate the association between exposures and hypertension. We identified 88 incident hypertension cases during two years of follow up. High BMI was associated with high risk of developing hypertension after adjusting for potential confounders. The adjusted hazard ratio for hypertension was 2.88 (95% CI: 1.24, 6.69) comparing two extreme BMI quartiles. Each SD increase of BMI (approximate to 1.85 kg/m(2)) was associated with a 32% higher likelihood to developing hypertension (Hazard ratio = 1.32; 95% CI: 1.003, 1.73). In contrast, we did not find significant associations between WC or PBF and higher hypertension risk (p-trend > 0.2 for both). Conclusion: High BMI, but not WC and PBF, was associated with high risk of hypertension in normal-weight Chinese children. (C) 2018 Published by Elsevier B.V. on behalf of The Italian Society of Diabetology, the Italian Society for the Study of Atherosclerosis, the Italian Society of Human Nutrition, and the Department of Clinical Medicine and Surgery, Federico II University.