Direct oral anticoagulants and warfarin in atrial fibrillation patients with cancer by anticoagulation quality

Background: Atrial fibrillation (AF) patients with cancer are frequently treated with vitamin K antagonists (VKAs). Direct oral anticoagulants (DOACs) benefit according to VKA quality has not been investigated in this high-risk population. The authors compared DOACs with VKAs on mortality, cardiovascular events (CVEs), and bleeding risk across time-in-therapeutic-range (TiTR) strata (< or ≥70%). Methods: AF patients with cancer from the nationwide Italian Survey on Anticoagulated Patients Register on oral anticoagulants were included. Propensity score matching (PSM) was performed. Results were expressed as hazard ratio (HR) and 95% confidence interval (CI) for all-cause mortality and as subdistribution HR (sHR) for CVEs and bleeding risk. Numbers-needed-to-treat (NNT) and numbers-needed-to-harm (NNH) were calculated. VKA patients were stratified by TiTR <70% or ≥70% and compared with DOACs users. Results: A total of 1605 patients were included (median, 78 years; 44.7% women). During a mean follow-up of 729.8 days, 153 deaths, 177 CVEs, and 90 bleedings occurred. After PSM, DOACs were associated with lower all-cause mortality (HR, 0.37, p < .001) and CVEs (sHR 0.58, p = .005) and similar bleeding risk compared to VKAs. The lowest NNT was observed at 24 months (28.2 for mortality and 37.8 for CVEs), whereas NNH was not significant. DOAC use was associated with lower mortality and CVEs risk in patients with TiTR <70%, and with lower mortality, similar CVEs risk and higher risk of bleeding for a TiTR ≥70%. Conclusion: DOACs may reduce mortality in AF patients with cancer regardless TiTR. The use of DOACs in high-bleeding risk patients with good TiTR should be cautious.