Abstract 15366: Cancer Diagnosis Following Bleeding in Patients With Atrial Fibrilation Undergoing Anticoagulation Therapy

Abstract

Introduction: Bleeding is frequent in patients with atrial fibrillation (AF) undergoing oral anticoagulation (OAC), and may be the first manifestation of underlying cancer. OAC could be usefull as a screening tool to unveil an occult cancer and enhance early diagnosis. Hypothesis: We aim to analyze whether bleeding represents an useful tool to unmasking an occult cancer in AF patients treated with OAC. Methods: We used a cohort including all patients ≥ 75 years-old from the health area of Vigo (Galicia, Spain) with AF between 2014 and 2017 (CardioCHUVI-AF_75 registry). Results: Of 8,753 AF patients evaluated (mean age, 82.7 years; women, 61.7%), 2,171 (24.8%) experienced any (major or non-major) bleeding and 479 (5.5%) were diagnosed with cancer (mean follow-up of 3 years). Among 2,171 who experienced bleeding, 198 (9.1%) were diagnosed with cancer. Patients with bleeding have a 3-fold higher risk of new cancer diagnosis compared with those without bleeding (4.7 per 100 patient/year vs1.4 per 100/patients year; hazard ratio [HR]: 3,72 [95% CI 3.05-4.55]). Gastrointestinal bleeding was associated with a 13-fold higher hazard of new gastrointestinal cancer diagnosis (HR 13.44 [95% CI 9.11-19.85]). Genitourinary bleeding was associated with an 18-fold higher hazard of new genitourinary cancer diagnosis (HR 18.11 [95% CI 12.52-26.20]). And bronchopulmonary bleeding was associated with a 15-fold higher hazard of new bronchopulmonary cancer diagnosis (HR 15.78 [95% CI 6.03-41.28]). For those other bleeding (non-gastrointestinal, non-genitourinary, non-bronchopulmonary), the HR for cancer was 2.31 (95% CI 1.47-3.64). Conclusions: Any gastrointestinal, genitourinary, or bronchopulmonary bleeding was associated with higher rates of new cancer diagnosis in AF patients undergoing OAC. These bleeding events behave as an useful screening tool and should encourage prompt investigation for underlying cancers at those sites.