ALONE-AF: Stopping OAC After Ablation Doesn’t Reduce Cognitive Function

CHICAGO, IL—When patients stop taking oral anticoagulation (OAC) after they’ve been free of atrial fibrillation (AF) recurrence for at least a year after catheter ablation, their cognitive function doesn’t appear to deteriorate, according to a substudy of the ALONE-AF trial.

On the contrary, scores on the Montreal Cognitive Assessment (MoCA) improved over 2 years of follow-up to a similar degree in the OAC and no-OAC groups, with consistent results seen across subgroups, Boyoung Joung, MD, PhD (Yonsei University College of Medicine, Seoul, Republic of Korea), reported here at Heart Rhythm 2026.

However, Joung said, the findings “should be interpreted with caution because the study actually was not designed to check the [difference in] cognitive function changes between the OAC and no-OAC groups.”

Prior research has shown that AF is associated with deterioration of cognitive function and the development of dementia. There is also some evidence that catheter ablation may lead to an improvement in cognitive function and that OAC may reduce dementia risk. It remains uncertain whether discontinuing OAC after successful AF ablation may precipitate a decline in cognitive function.

To explore that question, Joung and his colleagues performed a substudy of the ALONE-AF trial. As reported by TCTMD, the main trial showed that in patients with AF who did not have a documented recurrence of atrial arrhythmias at least a year (mean 3.6 years) after ablation, discontinuing OAC reduced a composite of stroke, systemic embolism, or major bleeding through 2 years of follow-up compared with continuing anticoagulation, with the difference driven by less bleeding in the no-OAC arm.

The new analysis, which was published simultaneously online in Heart Rhythm with first author Ho-Gi Chung, MD (Yonsei University College of Medicine), included 646 patients (mean age 63.9 years; 25.9% women) who completed the MoCA at both baseline and 2 years, representing 83.4% of the overall trial population.

Over 2 years, MoCA score improved both in the OAC arm (from 24.2 to 24.9 points) and in the no-OAC arm (from 24.4 to 25.0 points); the between-group difference in the change was not significant (P = 0.759). These findings were consistent across subgroups defined by age, sex, type of AF, the presence of cognitive impairment at baseline, prior stroke/TIA, and CHA₂DS₂-VASc score and across the seven cognitive domains of the MoCA.

The researchers also examined changes in the prevalence of cognitive impairment (MoCA score < 23 points) based on whether patients had a recurrence of AF during follow-up, finding a significant difference between groups (P = 0.036 for interaction). Cognitive impairment became less frequent among patients with no AF recurrence (from 26% to 22%; P = 0.002) but trended upward in those who did (from 22% to 28%; P = 0.173).

Joung, however, acknowledged some limitations of the study, including the possibility that it was underpowered to assess changes in cognitive function; the use of MoCA, which is a brief screening tool that might miss smaller changes in cognitive function that could be detected using more detailed neuropsychological tests; and the uncertain generalizability of the findings to populations outside of East Asia.

‘Early Ablation Is Better’

T. Jared Bunch, MD (University of Utah Health, Salt Lake City), the discussant following Joung’s presentation, congratulated the researchers for exploring brain injury other than stroke in patients with AF, noting that other outcomes, like cognitive dysfunction, can have effects on patients’ and caregivers’ quality of life.

He reviewed evidence suggesting that catheter ablation may reverse some of the damage to the brain induced by AF before pointing to another important aspect of the ALONE-AF cognitive function substudy.

Notably, the researchers showed that patients with cognitive impairment at baseline had a greater gain in MoCA score compared with those who had normal cognition (2.1 vs 0.1 points; P < 0.001 for interaction). That suggests that “early ablation is better,” Bunch said, underscoring that even if patients have cognitive decline, ablation will “impact their function and quality and quantity of life.”

Prior research has demonstrated, too, that ablation performs better than medical therapy for improving cognition in patients with AF, irrespective of whether they had cognitive dysfunction, Bunch highlighted.

“Ablation continues to show a durable improvement on multiple hard endpoints and evolving . . . cognitive endpoints that are meaningful to our patients,” he said.