Expanded normal weight obesity and blood pressure in Chinese adults: a community-based cross-sectional study

The study aimed to explore the independent association between expanded normal weight obesity categories and blood pressure among adults aged 20-80 years in China. By cross-sectional design, a total of 4279 adults living in Shaanxi Province, China, were selected from communities via multi-stage stratified cluster sampling in 2014. Information on anthropometric, body composition and blood pressure was collected and analysed. Expanded normal weight obesity (ENWO) categories were used to identify the level of bodyweight based on the combination of body mass index (BMI) and body fat percentage (BFP) categories. The age- and sex-standardised prevalence of hypertension increased within ENWO groups, from 10.12% in the underweight-low body fat group to 45.92% in the obesity-high body fat group. In under or normal weight participants, body fat percentage was found independently associated with hypertension in men, with an adjusted odds ratio of 3.69 in the fourth quartile of BFP compared with the first one. However, this effect was not observed in women. BFP was independently associated with increased risk of hypertension, especially in men. People with normal BMI should be re-identified as a high-risk population based on BFP level when it comes to hypertension prevention in primary healthcare settings.