Association of obesity categories and high blood pressure in a rural adult Chinese population.

Limited information is available on the prevalence of obesity and high blood pressure (HBP) in rural China. We conducted a cross-sectional survey in a rural adult Chinese population during July to August of 2007 and 2008. The relationship between various obesity categories and HBP was analysed by gender for 20 194 participants. Obesity categories were classified as general and central obesity in terms of body mass index (BMI) and waist circumference (WC), respectively; cross-classification of BMI and WC created another four groups: both BMI and WC normal (BNWN), BMI obesity and WC normal (BOWN), BMI normal and WC obesity (BNWO), and both BMI and WC obesity (BOWO). The rates of HBP for BNWN, BOWN, BNWO and BOWO groups were 20.8, 63.3, 39.8 and 48.7%, respectively, for men and 20.1, 28.0, 34.7 and 54.2%, respectively, for women. As compared with BNWN group, the adjusted odds ratio (OR) and 95% confidence interval (CI) of BOWN and BOWO for having HBP in men were 6.227 (2.712-14.300) and 4.842 (4.036-5.808), respectively. As compared with BNWN women, BNWO and BOWO women showed increased risk of HBP (adjusted OR=1.342, 95%CI=1.139-1.581 and adjusted OR=4.530, 95%CI=4.004-5.124, respectively). The prevalence of general and central obesity was strongly related to HBP. Men with obese BMI but normal WC may be at increased risk of HBP. Women should pay more attention to changes in visceral adipose distribution and keep both BMI and WC values within normal ranges to reduce obesity-related health problems.