Trends in Obesity and Metabolic Status Among a Health Check-Up Population in Beijing and Hunan Between 2012 and 2020

Background: Previous cross-sectional studies have reported the prevalence of obesity and metabolic status in China. However, the trend of change in obesity and metabolic status, especially in different sex and age groups are lacking. In current study, we collected more than 900,000 individuals' health check-up information to examine the trends in obesity and metabolic status among the Chinese population. Methods: In a series cross-sectional study, we analyzed the trends in obesity and metabolic status in a health check-up population from a mixed urban and rural area, stratified by sex and age in Beijing and Hunan from 2012 to 2020. Data on 256,782 participants surveyed between 2014 and 2020 in Beijing and 697,170 participants surveyed between 2012 and 2020 in Hunan were analyzed for obesity status. Of them, a total of 908,311 participants were used for metabolic status analysis. Anthropometrics, blood pressure measurements, and fasting blood tests (glucose, lipids) were performed according to standard protocols. Obese was defined as body mass index (BMI) ≥28 kg/m2. Mean values and prevalence of obesity and metabolic status were standardized to the age distribution of China population in 2010. Trends in obesity and metabolic status were evaluated using the Joinpoint software to estimate annual percentage changes in slopes. Findings: Based on age- and sex-standardized values, the mean BMI values among Beijing and Hunan participants were 23.94 (95%CI:23.93, 23.95) and 23.68 (95%CI: 23.67, 23.69) kg/m2, respectively. Between 2014-2020, the overall obesity prevalence among Beijing participants increased from 12.70% (95%CI:12.17%,13.23%) to 14.33% (95% CI:13.97%, 14.70%) (P=0.009), mainly derived by the 20-39 and 40-59 age groups. Moreover, in terms of metabolic ;status, the prevalence of metabolically healthy obese (MHO) significantly increased from 2.07% (95%CI: 1.84%, 2.30%) to 4.33% (95% CI: 4.13%, 4.53%) in Beijing. Between 2012-2020, no significant trend in obesity was found among overall Hunan participants (P=0.240), but the prevalence of metabolically unhealthy obese (MUO) significantly increased from 5.36% (95% CI: 5.18%, 5.54%) to 7.35% (95% CI: 7.11%, 7.58%), mainly derived by the 20-39 and 40-59 age groups. Interpretation: The recent trends in obesity and metabolic status among Hunan participants differed from that among Beijing participants. The Beijing area was dominated by the growth of young and middle-aged obesity and MHO phenotype, while although the overall obesity rate was stable in Hunan, the proportion of MUO increased, especially in young and middle-aged population. National weight control plan is needed in China, with a particular focus on young and middle-aged population. Funding Information: This work was supported by funding from the National Science Foundation of China (81973324, 81872685, and 82003537), Hunan Young Talent grant (2020RC3063), Hunan Science Foundation (2020JJ5858, 2020JJ4439) and the Wisdom Accumulation and Talent Cultivation Project of the Third XiangYa hosipital of Central South University (YX202002). Declaration of Interests: The authors report no conflicts of interest. Ethics Approval Statement: All participants signed informed consent forms, and the study was approved by the Ethics Committee of the Third Xiangya Hospital.