Search

Aims: The aim of this study was to determine the comparative effectiveness and safety of direct oral anticoagulants (DOACs) and warfarin in adults with atrial fibrillation (AF) by level of kidney function., Methods and Results: We pooled findings from five retrospective cohorts (2011-18) across Australia and Canada of adults with; a new dispensation for a DOAC or warfarin, an AF diagnosis, and a measure of baseline estimated glomerular filtration rate (eGFR). The outcomes of interest, within 1 year from the cohort entry date, were: (1) the composite of all-cause death, first hospitalization for ischaemic stroke, or transient ischaemic attack (effectiveness), and (2) first hospitalization for major bleeding defined as an intracranial, upper or lower gastrointestinal, or other bleeding (safety). Cox models were used to examine the association of a DOAC vs. warfarin with outcomes, after 1:1 matching via a propensity score. Kidney function was categorized as eGFR ≥60, 45-59, 30-44, and <30 mL/min/1.73 m2. A total of 74 542 patients were included in the matched analysis. DOAC initiation was associated with greater or similar effectiveness compared with warfarin initiation across all eGFR categories [pooled HRs (95% CIs) for eGFR categories: 0.74(0.69-0.79), 0.76(0.54-1.07), 0.68(0.61-0.75) and 0.86(0.76-0.98)], respectively. DOAC initiation was associated with lower or similar risk of major bleeding than warfarin initiation [pooled HRs (95% CIs): 0.75(0.65-0.86), 0.81(0.65-1.01), 0.82(0.66-1.02), and 0.71(0.52-0.99), respectively). Associations between DOAC initiation, compared with warfarin initiation, and study outcomes were not modified by eGFR category., Conclusion: DOAC use, compared with warfarin use, was associated with a lower or similar risk of all-cause death, ischaemic stroke, and transient ischaemic attack and also a lower or similar risk of major bleeding across all levels of kidney function., (© The Author(s) 2022. Published by Oxford University Press on behalf of the European Society of Cardiology.)

The utility of anticoagulants for ischemic stroke prophylaxis in elderly patients with chronic kidney disease (CKD) and atrial fibrillation remains uncertain. In this population-based retrospective cohort study, we determined the association of anticoagulant use with ischemic stroke or hemorrhage in elderly patients (66 years and older) with advanced chronic kidney disease (eGFR under 45 ml/min/1.73m 2 ) and atrial fibrillation. We followed 6,544 patients with CKD and new onset atrial fibrillation, of whom 1,475 filled a prescription for an anticoagulant. We used propensity-score matched Cox proportional hazards and competing risk models to determine the time to first event of ischemic stroke, hemorrhage or mortality. After matching to examine exposure to anticoagulants, 1,417 matched pairs were identified. The crude rate of ischemic stroke and hemorrhage were 41.3 and 61.3 with anticoagulants and 34.4 and 34.3 without anticoagulants per 100 person-years, respectively. The hazard ratios of ischemic stroke, hemorrhage, and mortality for receipt of an anticoagulation prescription were 1.10 (95% confidence interval, 0.78-1.56), 1.42 (1.04-1.93), and 0.74 (0.62-0.88) as compared to non-receipt of anticoagulation. After accounting for the competing risk of death, the hazard ratios for ischemic stroke and hemorrhage were 1.12 (0.90-1.39) and 1.60 (1.31-1.97), respectively. The findings were consistent in a sensitivity analysis accounting for time varying anticoagulant exposure. Thus, in older patients with CKD and atrial fibrillation, receipt of an anticoagulant was not associated with a lower risk of ischemic stroke, but a higher risk of hemorrhage and a lower risk of mortality., (Copyright © 2016 International Society of Nephrology. Published by Elsevier Inc. All rights reserved.)