Effectiveness and Safety of DOACs vs. VKAs in AF Patients With Cancer: Evidence From Randomized Clinical Trials and Observational Studies

Background: The use of direct oral anticoagulants (DOACs) is recommended as the preferred treatment drug in patients with nonvalvular atrial fibrillation (AF). However, the effectiveness and safety of DOACs compared with vitamin K antagonists (VKAs) in patients with cancer and AF are still controversial. Therefore, we performed a meta-analysis regarding the effectiveness and safety of DOACs vs. VKAs in AF patients with cancer. Methods: A search of the Pubmed and EMBASE databases until August 2021 was performed. Adjusted risk ratios (RRs) and 95% confidence intervals (CIs) were pooled using a random-effects model with an inverse variance method. Results: Thirteen studies were deemed to meet the criteria. For the effectiveness outcomes, the use of DOACs compared with VKAs use was significantly associated with decreased risks of stroke or systemic embolism (RR = 0.66, 95% CI: 0.54-0.80) and venous thromboembolism (RR = 0.40, 95% CI: 0.26-0.61), but not ischemic stroke (RR = 0.79, 95% CI: 0.56-1.11), myocardial infarction (RR = 0.78, 95% CI: 0.56-1.11), cardiovascular death (RR = 0.76, 95% CI: 0.53-1.09), and all-cause death (RR = 0.82, 95% CI: 0.43-1.56). For the safety outcomes, compared with VKAs use, the use of DOACs was associated with reduced risks of intracranial bleeding (RR = 0.60, 95% CI: 0.50-0.71) and gastrointestinal bleeding (RR = 0.87, 95% CI: 0.80-0.95). There were no significant differences in major bleeding (RR = 0.87, 95% CI: 0.74-1.04), major or nonmajor clinically relevant bleeding (RR = 0.87, 95% CI: 0.74-1.01), and any bleeding (RR = 0.88, 95% CI: 0.76-1.03). Conclusion: Compared with VKAs, DOACs appeared to have significant reductions in stroke or systemic embolism, venous thromboembolism, intracranial bleeding, and gastrointestinal bleeding, but comparable risks of ischemic stroke, myocardial infarction, cardiovascular death, all-cause death, major bleeding, major or nonmajor clinically relevant bleeding, and any bleeding in patients with AF and cancer.