Geographic Variation in Prevalence of Adult Obesity in China: Results From the 2013–2014 National Chronic Disease and Risk Factor Surveillance

Geographic Variation in Prevalence of Adult Obesity in China: Results From the 2013–2014 National Chronic Disease and Risk Factor Surveillance Background: Obesity prevalence has grown rapidly worldwide. According to the World Health Organization, the global prevalence of obesity nearly doubled between 1980 and 2008. This increase in obesity prevalence has been observed in China as well, but most national efforts have focused on childhood obesity (1). Data from the first China Chronic Disease and Risk Factor Surveillance (CCDRFS) in 2004 indicate that the prevalence of general obesity (defined as a body mass index [BMI] ≥30 kg/m) among adults was 3.3% and that 25.9% of participants were considered to have abdominal obesity on the basis of criteria at that time (a waist circumference [WC] ≥90 cm for men and ≥80 cm for women). The more recent national estimates of adult obesity in China, which lack provincial prevalence estimates, were made in 2007 and 2010 and indicate that the prevalence of general obesity was 3.1% and 5.2%, respectively, and the prevalence of abdominal obesity 27.5% and 32.3%, respectively. An updated estimate is urgently needed to develop more efficient health interventions and policies. Objective: To estimate the national and provincial prevalence of general and abdominal obesity among Chinese adults and by sex. Methods and Findings: The CCDRFS is an official, nationally representative, successive, cross-sectional survey that has been done every 3 years since 2004. We used the wave of CCDRFS conducted from August 2013 to April 2014. The CCDRFS uses a complex, multistage, probability sampling design to provide a representative sample of Chinese adults aged 18 years or older (2). Anthropometric variables were measured on the day of the face-to-face interview. After participants removed heavy clothes and shoes, trained personnel used standardized techniques and protocols to measure height, weight, and WC to the nearest 0.1 cm, 0.1 kg, and 0.1 cm, respectively. The BMI was calculated by dividing weight (in kilograms) by squared height (in meters). Current Chinese criteria define general obesity as a BMI of 28 kg/m or higher and abdominal obesity as a WC of at least 90 cm for men and at least 85 cm for women. According to criteria from the World Health Organization, general obesity is defined as a BMI of 30 kg/m or higher; according to criteria from the National Heart, Lung, and Blood Institute, abdominal obesity is defined as a WC of at least 102 cm for men and at least 88 cm for women. After exclusion of 1694 persons with missing anthropometric measurements (weight, height, or WC), 174 840 participants were included in the analysis. The study protocol was approved by the ethical review committee of the National Center for Chronic and Noncommunicable Disease Control and Prevention of the Chinese Center for Disease Control and Prevention. All participants provided written informed consent. The weighted prevalence of general and abdominal obesity at the province level was calculated and mapped by sex, where survey weights accounted for the complex survey design and nonresponse, and prevalence estimates were nationally representative of the Chinese adult popuFigure 1. The weighted prevalence (95% CI) of general obesity in men (A), general obesity in women (B), abdominal obesity in men (C), and abdominal obesity in women (D) across provinces of China.