Risk of heart failure among colon and rectal cancer survivors: a population‐based case–control study

AIMS: This population‐based case–control study aims to investigate the occurrence of heart failure (HF) among colon and rectal cancer survivors compared with a cancer‐free control population taking into account pre‐existing cardiovascular risk factors and the influence of treatment. METHODS AND RESULTS: Colon and rectal cancer survivors diagnosed between 2007 and 2014 were selected from a linked cohort of cancer and primary care data in the Netherlands and matched based on gender, birth year, general practitioner (GP) practice, and follow‐up period to cancer‐free controls. The occurrence of HF was identified based on GP recorded diagnoses after index date (diagnosis date for cases). A Cox proportional hazards model was used to estimate hazard ratios (HRs), adjusted for age, sex, hypertension, diabetes, and hypercholesterolaemia. A total of 5333 colon cancer cases and 2468 rectal cancer cases could be matched to a total of 31 204 cancer‐free controls. A statistically significant increased risk of HF was seen among all cases compared with cancer‐free controls (HR 1.33; 95% confidence interval: 1.12–1.59). This was also seen when analysing colon cancer and rectal cancer separately. Being diagnosed with stage IV cancer, having hypertension, or having hypercholesterolaemia statistically significantly increased the risk of HF among colon cancer. Hypertension was a statistically significant risk factor for developing HF among rectal cancer cases. CONCLUSIONS: Colon and rectal cancer survivors are at increased risk for developing HF. More awareness should be created by treating physicians and GPs for this potential increased risk in order to further improve survival.