Analysis on relationship between body mass index and blood pressure in children and adolescents in Zhejiang province.

Objective To identify the relationship of body mass index(BMI) and blood pressure in children and adolescents aged 10-18 years in Zhejiang province.Methods A total of 5 528 students aged 10-18 years were selected as research subjects by stratified cluster sampling method.The category criterion of overweight and obesity in children and adolescents of China was recommended by the Working Group on Obesity in China(WGOC).The category criterion of hypertension in children was recommended by China′s National Group on Students′ Constitution and Health Survey.Statistical methods including partial pearson correlation analysis,χ2 test and Logistic multiple regression were used to analyze the data from the subjects.Results ①The overweight rates were 10.18% and 9.97%,and the obesity rates were 4.82% and 3.75%,respectively for male and female students.②After adjustment for age and gender,body mass index(BMI)was found to be independently positively correlated with systolic blood pressure(SBP)and diastolic blood pressure(DBP)(r=0.336,0.221,respectively,P0.001).③The means of SBP and DBP were ranked as follows(in decreasing order):those in obesity group,in overwight group,and in normal weight group(P0.001).④The prevalence rates of hypertension in overweight and obesity groups were 12.07% and 22.69%,respectively.Compared with the normal weight group,the relative risks(RRs) for hypertension in overweight and obesity groups were 2-3 and 4-7,respectively.Logistic multiple regression analysis revealed that age and weight were both influencing factors of SBP and DBP(P0.001).After age adjustment,the RRs were both 2-3 between obesity and overweight groups as well as between overweight and normal weight groups.Conclusion BMI is positively correlated with SBP and DBP in children and adolescents aged 10-18 years in Zhejiang province.Overweight and obesity may increase risk of hypertension,indicating that weight control in children and adolescents is important for hypertension prevention and control.