Body mass index and waist circumferences positively associated with hypertension:a three-year follow-up study in Nanjing

Objective To explore whether the increase of body mass index (BMI)and waist circumferences (WC) can predict the higher risk of hypertension in residents of Nanjing.Methods Population-based cross-sectional study was conducted in local residents older then 35 years in three urban districts and one rural county in July 2004.The subjects without hypertension in the baseline survey were selected to participate the follow-up survey in Oct.2007.Logistic regression models were used to estimate the relative risk (RR) of developing hypertension associated with BMI and WC in baseline and the three-year change of BMI and WC.Results The cumulative hypertention incidence of men and women was 6.0% and 5.4%,respectively (χ2=0.32,P0.05) during the 3 years of follow-up.The risk of developing hypertension rose with the increase of either BMI or WC in baseline.Compared with the group with neither general obesity(defined by BMI) nor abdominal obesity (defined by WC),the group with both general obesity and abdominal obesity had the highest risk(for male,RR=2.395,95%CI:1.672～3.341,for female,RR=2.550,95%CI=1.809～3.395).Conclusion Overweight and abdominal obesity were important independent risk factors of hypertension.The increase of BMI and WC can predict the higher risk of the development of hypertension.