Atrial fibrillation is a well-established risk factor for stroke, but its role in cognitive decline following ischemic stroke remains underexplored. This study investigates the impact of AF on cognitive outcomes across different severities of ischemic stroke, aiming to better understand the interplay between AF and post-stroke cognitive function.

We conducted a post hoc analysis using data from the ELAN randomized clinical trial, involving 600 patients who experienced ischemic strokes of varying severity. Stroke severity was categorized as minor, moderate, or major. Cognitive function was assessed using standardized cognitive scales both before and after the stroke event. AF status was determined through clinical assessments and patient medical history, and the analysis focused on comparing cognitive outcomes between patients with and without AF. Additionally, the influence of early anticoagulation therapy on cognitive decline in AF patients was evaluated.

The analysis revealed that patients with AF exhibited a significantly higher risk of cognitive decline following ischemic strokes of all severities. Specifically, the odds ratios for cognitive decline were 1.45 (95% CI: 1.10-1.93) for minor strokes, 1.68 (95% CI: 1.25-2.24) for moderate strokes, and 2.03 (95% CI: 1.54-2.66) for major strokes in patients with AF compared to those without AF. Furthermore, multivariate analysis highlighted that early initiation of anticoagulation therapy played a protective role, moderating the extent of cognitive decline in AF patients.

This study highlights the strong association between atrial fibrillation and increased cognitive decline after ischemic stroke. Early anticoagulation therapy plays a protective role. Routine cognitive assessments and proactive AF management should be integral to post-stroke care, offering a potential pathway to reduce cognitive impairment and improve recovery outcomes.