Does heart failure increase the risk of incident cancer? A meta-analysis and systematic review

Recently, several studies have demonstrated that heart failure (HF) may increase the risk of incident cancer. However, this association has not been statistically and systematically verified by any comprehensive pooled analyses. We performed a meta-analysis on cancer morbidity and co-mortality of adults with HF in a large sample size to explore the relationship between HF and the risk of developing cancer. From inception to April 2019, we searched PubMed and EMBASE for published relevant articles on patients with HF diagnosed with cancer afterwards, with reported outcomes of morbidity and mortality. Two investigators independently reviewed these included studies. Study data were independently extracted using predefined data extraction forms. Random and fixed-effects models were fit for the study duration. This analysis consisted of 4 cohort studies comprising 5,004,251 participants. The relative risk (RR) for incident cancer was 1.22 (95% confidence interval (CI), 1.13-1.33) indicating that patients with HF may have a higher risk of developing cancer. The pooled RR of co-mortality was 2.03 (95% CI, 1.13-3.65), indicating that HF associated with cancer increases the risk of mortality. In this meta-analysis and systematic review, our results demonstrated that heart failure may increase the risk of incident cancer and that HF associated with cancer increases the risk of mortality.