Association between body composition and subsequent cardiovascular diseases among 5-year breast cancer survivors

Purpose: Cardiovascular diseases (CVDs) remain one of the leading causes of mortality in breast cancer survivors. This study aimed to investigate the association between body composition and subsequent CVDs in breast cancer survivors. Methods: A retrospective cohort study of more than 70 thousand 5-year breast cancer survivors aged 40 years or older was conducted using data from the National Health Insurance Service of South Korea. Based on the percentage of predicted lean body mass (pLBMP), appendicular skeletal muscle mass (pASMP), and body fat mass (pBFMP), which were calculated using prediction equations with anthropometric data and health habits, groups were equally divided into quartiles. The risk of CVD was evaluated using multivariate Cox proportional hazards regression. Results: Compared to those with the lowest pLBMP and pASMP, those with the highest pLBMP and pASMP had a 37% and 42% lower risk of CVDs, respectively. In contrast, those with the highest pBFMP had a 57% higher risk of CVDs compared to those with the lowest pBFMP. Each 1 % increase in pLBMP and pASMP was associated with a decreased risk of CVDs [pLBMP, adjusted hazard ratio (aHR): 0.96, 95% CI 0.94–0.98, p<0.05; pASMP, aHR: 0.91, 95% CI 0.87–0.95, p <0.05] while each 1 % increase in pBFMP was associated with the increased risk of CVDs (aHR: 1.05, 95% CI 1.03–1.07, p <0.01). Conclusions: In this cohort study, high pLBMP, a high pASMP, and a low pBFMP were associated with reduced risk of CVDs.