Statins and the risk of dementia in patients with atrial fibrillation: A nationwide population-based cohort study

Background Atrial fibrillation (AF) is associated with cognitive decline and may contribute to an increased risk of dementia. The goal of the present study was to investigate whether statin use prevented non-vascular dementia in subjects with AF. Methods Data from the National Health Insurance Research Database of Taiwan were used in this study. The study group comprised 51,253 AF subjects aged ≥ 60 years who had received statin treatment. For each study patient, four age- and sex-matched AF subjects without statin exposure were selected as the control group (n = 205,012). The risk of non-vascular dementia was compared between the statin and control groups. Results During the follow-up period, 17,201 patients experienced non-vascular dementia. The annual incidence of non-vascular dementia was lower in the statin group than in the control group (1.89% vs. 2.20%; p < 0.001). Statin use exhibited a protective effect on the occurrence of non-vascular dementia, with an adjusted hazard ratio (HR) of 0.832 (95% confidence interval = 0.801-0.864). Among statin types, the use of rosuvastatin was associated with the largest risk reduction (adjusted HR = 0.661). Statin exposure duration was related inversely to the risk of non-vascular dementia. Conclusions In this large-scale nationwide cohort study, statin use was associated with a lower risk of non-vascular dementia in AF. Use of more potent statin and longer exposure time may be associated with greater benefits.