Abstract 13013: Bleeding Risk and Major adverse Events in Patients With Cancer on Oral Anticoagulation Therapy

Abstract

Introduction: Bleeding and thromboembolism are the major concerns for oral anticoagulation therapy (OAT), especially in atrial fibrillation (AF) patients with history of cancer. The aim of this study was to evaluate the usefulness of OAT in AF patients with cancer for protecting major stroke and brain hemorrhage. Methods: The study included 2,168 AF patients with cancer at a tertiary hospital. We compared composite end points including major adverse cardiac events (MACE) and major bleeding between patients with OAT (OAT+, n=1,182) and without OAT (OAT-, n=936). Results: CHA 2 DS 2 -VASc and HAS-BELD score were higher in OAC+ than OAT- group. During the follow up period of 3.9 ± 2.8 years, 142 (12%) and 88 (9%) patients had MACE in OAT+ and OAT-, respectively (p = 0.055). Major bleeding (11% vs. 8%, p=0.023) and composite endpoints (21% vs. 16%, p = 0.002) were significantly higher in OAT+ than OAT- group. OAT+ patients had lower cumulative survival free of composite endpoints than OAT- patients (p=0.024). Among 230 MACE and 207 major bleeding events, 117 (47%) and 86 (42%) events occurred within first year after the diagnosis of cancer. During this period, optimal INR level was achieved in only 288 (24%) patients because of cancer treatment. OAT failed to prevent MACE in stomach and renal cancer patients with statistical significance (Figure 1A*). Furthermore, OAT+ patients with prostate, thyroid, pancreato-biliary, head-neck and breast cancers tended to have more MACE than OAT- group. Conclusion: In AF patients with cancer, composite end point including MACE and bleeding was not improved by OAT at the first year because of poor control of INR. Therefore, meticulous control of INR is needed in these patients. Moreover, OAT might fail to prevent MACE in specific cancers.