Oral Anticoagulation for Atrial Fibrillation in Octogenarians Across the Renal Function Spectrum

Our study aimed to describe the efficacy and safety of oral anticoagulation (OAC) use in octogenarians with atrial fibrillation (AF) across the spectrum of renal function.

Data for this study were sourced from AF Research Database (NCT03760874). AF patients aged ≥ 80 who received OAC treatment, both direct oral anticoagulant (DOAC) and vitamin K antagonist (VKA) were selected. Participants were categorized in 2 groups according to creatinine clearance (CrCl) ≥ 45 and < 45 ml/min/1.73 m². The primary safety outcome was the occurrence major bleeding. The primary effectiveness outcome was the occurrence of thromboembolic events.

A total of 901 AF patients (median age 84 [4.9] years; 44% men) with age ≥ 80 years on treatment with DOACs (n: 629, 70%) and VKA (n: 272, 30%) were included in the study. 303 patients (34%) had CrCl < 45 ml/min/1.73m2 and 598 (66%) had CrCl ≥ 45 ml/min/1.73m2. No significant differences were shown in major bleedings, minor bleedings and thromboembolic events between patients on DOACs vs VKAs, both in the group with CrCl ≥ 45 than < 45 ml/min. In the group with CrCl < 45 ml/min/1.73 m², a total of 72 patients (23%) died during the follow-up, with higher mortality in VKA group compared to DOACs (45% vs 15%; p < 0.001). At multivariate regression analysis, age [OR: 1.15; p = 0.001] and coronary artery disease (CAD) [OR: 1.74; p = 0.04] were independently associated with mortality; in contrast, the use of DOACs were inversely associated with mortality [OR = 0.26; p < 0.001]. In patients with CrCl ≥ 45 ml/min/1.73 m², DOACs group experienced less intra-cranial hemorrhage (ICH) (0.2% vs 2.8%; p = 0.01) compared to VKAs. VKAs patients showed higher mortality compared to those on DOACs (29.1% vs 7.9%; p < 0.001). At multivariate regression analysis, chronic heart failure [OR = 2.14; p = 0.01] was independently associated with death, whereas male gender [OR: 0.45; p = 0.009] and the use of DOACs [OR: 0.29; p < 0.001] were associated with lower mortality.

DOACs seem to be safe and effective in octogenarians with chronic kidney disease at stage ≥ G3b. As compared with VKA administration, the use of DOACs was associated with lower mortality rates among AF octogenarians with renal dysfunction.