Cardiovascular disease incidence and cancer risk in two large European prospective cohorts.

Abstract

Our study investigated the association between incident cardiovascular disease (CVD) and subsequent cancer risk in two large European prospective cohorts. We included 568,926 adults from the European Prospective Investigation into Cancer and Nutrition and United Kingdom Biobank, all of whom were free of CVD, cancer and type 2 diabetes at baseline. Multivariable Cox proportional hazards regression models were used to estimate cancer hazard ratios (HRs) and 95% confidence intervals (CIs) in relation to incident CVD events. CVD was treated as a time-varying exposure, and models accounted for time since CVD diagnosis and other lifestyle factors. Study-specific estimates were pooled using meta-analysis. Over a median follow-up of 10.9 years, 51,559 participants developed cancer, including 2344 with a prior CVD diagnosis. In men and women combined, CVD was associated with a higher risk of cancer within the first year after diagnosis of CVD (hazard ration [HR] = 1.65, 95% CI: 1.46-1.86), but not between 1 and 5 years (HR = 1.05, 95% CI: 0.94-1.19) or after 5 years of CVD diagnosis (HR = 1.01, 95% CI: 0.93-1.09). Results were consistent across both cohorts. In sex-specific analyses, CVD was associated with an increased cancer risk 1-5 years post-diagnosis in women (HR = 1.13, 95% CI: 1.06-1.21), while in men, no such association was observed (HR = 1.02, 95% CI: 0.90-1.16). Men with a newly diagnosed CVD had a higher cancer risk within the first year of CVD, likely due to overdiagnosis, but no association was observed beyond 1 year. In women, a diagnosis of CVD was associated with an increased risk of cancer for up to 5 years post-diagnosis, suggesting that cancer overdiagnosis is less likely. These findings should be interpreted given the lack of CVD medication data.