FINDINGS from a recent study demonstrated that discontinuing oral anticoagulation (OAC) significantly increases the risk of recurrent ischemic stroke (IS) in patients with atrial fibrillation (AF). This nationwide cohort study, conducted in Denmark, involved 8,119 patients aged 50 years or older who had experienced an initial ischemic stroke and had either started or restarted OAC treatment after discharge between January 2014 and December 2021. The findings underscore the critical importance of continuous OAC therapy in preventing recurrent strokes in this high-risk population.
The study followed patients with recurrent IS until June 2022, with data analysis conducted between May 2023 and April 2024. A nested case-control analysis within the cohort matched patients with recurrent IS with controls still on OAC who had not yet experienced a stroke. The primary aim was to determine the risk of recurrent IS associated with OAC discontinuation compared to ongoing OAC use.
The average age of study participants was 78.4 years, with 54.1% male. Over an average follow-up period of 2.9 years, 663 patients experienced a recurrent IS, with a significant 80.4% of these patients on OAC at the time of their recurrent stroke. The crude cumulative incidence of recurrent IS at one year was found to be 4.3%, while the cumulative incidence of all-cause mortality was 15.4%. These rates remained consistent in adjusted analyses, reinforcing the robustness of the findings.
The nested case-control analysis revealed that patients who discontinued OAC had a notably higher risk of recurrent IS. Specifically, 13.4% of patients who stopped OAC suffered a recurrent stroke, compared to 6.8% of those who continued OAC, yielding an adjusted odds ratio of 2.13. This doubling of risk underscores the pivotal role of maintaining OAC therapy in reducing the likelihood of recurrent strokes.
The study authors concluded that the results highlight the high risks of recurrent IS and mortality in patients with AF despite secondary prevention with OAC. Moreover, the findings strongly advocate for continuous OAC treatment and call for enhanced secondary stroke prevention strategies in patients with AF to mitigate these risks effectively.
Reference:
Hindsholm MF et al. Recurrent ischemic stroke in patients with atrial fibrillation while receiving oral anticoagulants. JAMA Neurol. 2024;DOI:10.1001/jamaneurol.2024.1892.
