Associations of Changes in Weight and Waist Circumference with Cardiovascular Disease and Mortality in Chinese Adults

Background: The associations of age-related changes in body weight and waist circumferences with cardiovascular disease (CVD) and mortality remain unclear. Methods: We assessed changes in weight and waist circumference from baseline survey and resurvey among 27 964 participants in the China Kadoorie Biobank (CKB, 2004-2008) and Dongfeng-Tongji Cohort (DF-TJ, 2008-2013). We used Cox proportional hazards models to evaluate the associations between adiposity changes and the subsequent risks of incident CVD, CVD mortality and all-cause mortality. Findings: On average, during a median of 3·4 years from baseline to resurvey, participants experienced a weight loss of 0·6 kg, accompanied by a 2·1 cm increase in waist circumference. We identified 3589 incident CVD cases, 485 CVD deaths, and 1283 all-cause deaths during the follow-up in the CKB (2008-2016) and DF-TJ (2013-2016). Weight loss and waist gain were associated with increased risks of those outcomes in the two cohorts. In particular, compared with participants who had stable waist (waist change -2·0 to 7·0 cm) and weight (weight change -2·5 to 2·5 kg), those who gained waist but lost weight (waist circumference change >7·0 cm, weight change ≤ -2·5 kg) had the highest risk of incident CVD, CVD mortality and all-cause mortality, with the pooled multivariate hazard ratios (HRs) of 1·41 (95% CI, 1·13 to 1·75), 2·48 (1·40 to 4·37), and 1·71 (1·16 to 2·51), respectively. Among the weight-stable participants, waist circumference was linearly associated with CVD risk, with 17% higher risk (HR 1·17, 1·04 to 1·32) for those gained waist while 13% lower risk (HR 0·87, 0·77 to 0·99) for those lost waist compared to waist-stable participants. Interpretation: Increased waist circumference with concurrent weight loss is significantly associated with increased risks of CVD morbidity, CVD mortality, and all-cause mortality among Chinese middle-aged and elderly adults. Funding Statement: This work was partly supported by grants from the Foundation of National Key Programs of Research and Development of China (2016YFC0900800, 2016YFC0900500, 2017YFC0907501 and 2017YFC0907504), the National Natural Science Foundation of China (91643202 and 81390540), the 111 Project and the Program for Changjiang Scholars and Innovative Research Team in University. The China Kadoorie Biobank baseline survey and the first resurvey were supported by the Kadoorie Charitable Foundation in Hong Kong. The long-term follow-up has been supported by the UK Wellcome Trust (grants 088158/Z/09/Z, 104085/Z/14/Z), and the Chinese Ministry of Science and Technology (2011BAI09B01). The British Heart Foundation, UK Medical Research Council, and Cancer Research provide core funding to the Clinical Trial Service Unit and Epidemiological Studies Unit at Oxford University for the project.Declaration of Interests: The authors declare no competing interests.Ethics Approval Statement: The CKB study was approved by the ethics committees or institutional review boards at the University of Oxford, the Chinese Center for Disease Control and Prevention (China CDC), the Chinese Academy of Medical Sciences. The DF-TJ cohort was approved by the ethics committees of Tongji Medical College and the Sinopharm Dongfeng General Hospital. All participants provided written informed consents.