ABSTRACT
ABSTRACT: Limited literature has established the role of direct oral anticoagulants (DOAC) for elderly patients with nonvalvular atrial fibrillation who are unsuited for warfarin. Therefore, the objectives of this study were to assess the effectiveness and safety of DOAC use in this vulnerable patient population. This was a retrospective propensity score matching cohort study. Among all patients aged 75+ years who were not candidates for warfarin, we matched those who initiated DOAC between September 2017 and September 2018 with those who did not receive DOAC or warfarin in a 1:1 ratio. Effectiveness outcome was a composite measure of stroke, transient ischemic attack, and pulmonary embolism. Safety outcome was a composite measure of non-trauma-related intracranial hemorrhage and gastrointestinal bleed. Unless patients died or lost membership, follow-up period for the effectiveness outcome was until the end of 2019, whereas the safety outcome was for a period up to 1 year. Conditional logistic regression was used to analyze both outcomes. We identified 7818 patients who met the inclusion criteria and started DOAC, which matched to 7818 patients who did not receive anticoagulants. The mean age was 82.3 ± 5.1 years, and 51.5% male. The DOAC group had a lower hazard ratio of 0.37 (confidence interval, 0.24-0.57; P < 0.01) for composite effectiveness outcomes, whereas no difference in the composite safety outcome (hazard ratio, 0.91; confidence interval, 0.65-1.25; P = 0.55) when compared with matched control. In conclusion, DOAC was found to be effective in preventing thromboembolic events in patients aged 75+ years with nonvalvular atrial fibrillation who were not eligible for warfarin.
