Associations of short-term changes in obesity indices with all-cause mortality and cardiovascular disease

Objective: This study aimed to investigate how short-term changes (1-, 3-, and 5-year) in obesity measures affect mortality and cardiovascular disease (CVD) risk. Methods: We analyzed longitudinal data from the MJ Health Centre (n = 43,304 for the 1-year study; 24,295 for the 3-year study; 16,138 for the 5-year study) with median follow-up periods of 15.8, 13.9, and 12.3 years, respectively. Associations of short-term obesity indices changes with mortality and Framingham Risk Score changes were explored using time-dependent coefficient Cox regression models, restricted cubic splines, and multivariable linear regression models. Results: All-cause mortality was negatively associated with short-term weight and BMI changes, with greater reductions causing poorer outcomes. Compared with stable groups, short-term reduced weight and BMI were associated with greater risks of all-cause mortality and CVD-specific mortality (5-year study only). Also, either 1- and 3-year reduced or 3-year increased waist circumference and waist to height ratio were related to higher all-cause and CVD deaths than stable groups, respectively. Nonlinear relationships indicated lower cutoff values for short-term changes in obesity indices in predicting all-cause mortality. Decreased obesity indices significantly improved CVD profiles. Conclusions: Short-term changes in obesity indices show complex mortality risks, urging personalized approaches beyond a simple weight loss focus.