Change in Body Mass Index and Cardiovascular Outcomes in Patients With Cancer.

OBJECTIVE: To investigate the association between body mass index (BMI) changes and the risk of cardiovascular disease (CVD) in patients with cancer.

PATIENTS AND METHODS: This retrospective observational study used data from the JMDC Claims Database obtained between January 2005, and April 2021. We included 52,344 individuals (median [IQR] age, 53 years [46 to 60 years]; 23,584 [45.1%] men) with cancer and no prior CVD. Patients were classified into 3 groups based on the percentage change in BMI from the initial health checkup to the checkup 1 year later: -5.0% or less (BMI loss), -5.0% to 5.0% (stable BMI), and 5.0% or more (BMI gain). The primary end point was composite CVD events including heart failure, atrial fibrillation, ischemic heart disease, and stroke.

RESULTS: During a median follow-up period of 763 days (IQR, 369 to 1274 days), 3124 composite CVD events were observed. Compared with stable BMI, the hazard ratios (HRs) of BMI loss and gain for CVD events were 1.16 (95% CI, 1.00 to 1.34) and 1.10 (95% CI, 0.96 to 1.25), respectively. A U-shaped association was observed between the BMI changes and CVD events, particularly for nonatherosclerotic CVD outcomes including heart failure and atrial fibrillation. Compared with stable BMI, both BMI loss and gain increased the risk of heart failure (HR, 1.30; 95% CI, 1.08 to 1.57 and HR, 1.22; 95% CI, 1.02 to 1.47, respectively) and atrial fibrillation (HR, 1.70; 95% CI, 1.18 to 2.45 and HR, 1.55; 95% CI, 1.07 to 2.24, respectively).

CONCLUSION: Cancer survivors with BMI loss and gain were at greater risk of CVD. Body mass index loss is associated with a higher risk of CVD.