Bleeding and thrombotic events in atrial fibrillation patients with cancer: a systematic review and meta-analysis

Atrial fibrillation (AF) and cancer are frequently coexisting in elderly patients. Pooled metanalytic data on the impact of cancer on clinical outcomes in AF patients are lacking. We performed a systematic review and meta-regression analysis of clinical studies retrieved from Medline (PubMed) and Cochrane (CENTRAL) databases according to PRISMA guidelines. Bleeding endpoints included any, major, gastrointestinal (GI) bleeding and intracranial haemorrhage (ICH). Cardiovascular (CV) endpoints included myocardial infarction (MI), ischemic stroke/systemic embolism (IS/SE), CV and all-cause death. PROSPERO registration number: CRD42022315678. We included 15 studies with 2,868,010 AF patients, of whom 479,571 (16.7%) had cancer. The pooled hazard ratio (HR) for cancer was 1.43 (95% confidence interval [95%CI] 1.42-1.44) for any bleeding, 1.27 (95% CI 1.26-1.29) for major bleeding, 1.17 (95% CI 1.14-1.19) for GI bleeding, and 1.07 (95% CI 1.04-1.11) for ICH. The risk of major bleeding increased with the proportion of breast cancer. Cancer increased the risk of all-cause death (HR 2.00, 95% CI 1.99-2.02) whereas no association with MI and CV death was found. Patients with AF and cancer were less likely to suffer from IS/SE (HR 0.91, 95% CI 0.89-0.94). Cancer complicates the clinical history of AF patients, mainly increasing the risk of bleeding. Further analyses according to the type and stage of cancer are necessary to better stratify bleeding risk in these patients.