Risk factors for major bleeding in patients with atrial fibrillation and CKD G3-G5D on oral anticoagulants

Background Patients with chronic kidney disease (CKD) and atrial fibrillation (AF) on oral anticoagulants (OAC) are at high risk of bleeding. Determinants of major bleeding risk in OAC-users with AF and CKD are not well established and available bleeding score systems do not perform well in CKD. This study aims to present risk factors associated with major bleeding in a Swedish cohort of OAC- treated patients with CKD GFR category 3–5D (G3-G5D). Methods A Swedish register-based cohort study including patients with AF and G3-G5D on warfarin or DOAC between 2009–2018. Data collected from high quality registers including Swedish Renal Registry and Auricula, a register for AF and oral anticoagulants. Risk factors for major bleeding were investigated with Cox regression analysis. Results Of 2453 included patients 59% were on warfarin (time in therapeutic range 67%) and 41% on DOAC. Major bleeding rates were 8.9/100 patient-years. Factors associated with increased bleeding risk were GFR category, G5/5D versus G3, hazard ratio 1.92 (95% confidence interval 1.43–2.56), previous gastrointestinal bleeding, 1.77 (1.39–2.25), previous other bleeding 1.33 (1.09–1.62), congestive heart failure 1.36 (1.11–1.68), male sex 1.28 (1.03–1.60) and vascular disease, 1.35 (1.01–1.79). Conclusion Patients with AF and G3-G5D on OAC are at high risk of bleeding. Previous major bleeding and kidney failure are strongly associated with major bleeding. The present study also shows an association between OAC-associated bleeding and male sex, congestive heart failure and vascular disease. Knowledge about determinants of bleeding in advanced CKD is essential when deciding on when to anticoagulate or not.