BACKGROUND Although early rhythm control (ERC) in patients with atrial fibrillation (AF) reduces the risk of stroke, there is no evidence thus far on whether ERC reduces the risk of developing dementia in patients with AF and prior stroke.

OBJECTIVES This study sought to evaluate whether ERC reduces the risk of developing dementia in patients with new-onset AF and prior stroke.

METHODS Using the Korean nationwide claims database, we identified patients with new-onset AF and prior stroke between 2010 and 2016. Patients who received rhythm control therapy within 1 year after AF onset were defined as the ERC group, otherwise patients were categorized as the usual care group. A propensity score weighting method was used to balance the 2 groups. Incident dementia defined by relevant diagnostic codes was evaluated.

RESULTS A total of 41,370 patients were included (mean age 70 ± 11 years; mean CHA₂DS₂-VASc score 5.3 ± 1.6): 10,213 in the ERC group and 31,157 in the usual care group. Compared with usual care, ERC was associated with lower risks of all dementia, Alzheimer's dementia, and vascular dementia (weighted HR: 0.825 [95% CI: 0.776-0.876], 0.831 [95% CI: 0.774-0.893], and 0.800 [95% CI: 0.702-0.913], respectively, all P < 0.001). The benefit of ERC was slightly accentuated in the younger age group (<65 years). The beneficial effect of ERC in reducing the risk of dementia was consistent regardless of the characteristics of prior stroke.

CONCLUSIONS ERC might be beneficial in the prevention of dementia in patients with AF and prior stroke. To prevent the progression of cognitive dysfunction, ERC should be considered in this population.