Dose-Dependent Effect of Aspirin Use in Reducing Diabetes-Associated Dementia Risk Among Elderly Patients With Type 2 Diabetes Mellitus

Objective This study investigated the association between aspirin use and diabetes-associated dementia in older patients with type 2 diabetes mellitus (T2DM), assessing aspirin's potential protective effects, intensity of use, and dose-dependency against dementia. Design A cohort study evaluating the dose-dependent protective impact of aspirin against dementia in a population-based sample. Setting and Participants Older patients with T2DM (≥60 years), comparing aspirin users with nonusers. Methods Used a time-varying Cox hazards model to assess dementia incidence. Results Older aspirin users exhibited a significant reduction in dementia risk (adjusted hazard ratio [aHR], 0.44; 95% CI, 0.41–0.46). The lowest aHRs for dementia were observed at a daily intensity of 0.91 defined daily doses (DDDs), and higher daily dosages (>0.91 DDD) showed gradually increasing aHRs (although still <1). Analysis of cumulative DDD revealed a dose-response relationship, with progressively lower aHRs across quartiles (0.16, 0.42, 0.57, and 0.63 for quartiles 4, 3, 2, and 1, respectively) compared with never aspirin users (P for trend < .0001). Conclusions and Implications Aspirin use in older patients with T2DM significantly reduces dementia risk. The optimal daily intensity of aspirin use (0.91 DDD) is associated with the lowest aHR for dementia. These findings suggest a dose-dependent relationship, supporting the potential benefits of higher cumulative dosages of aspirin in reducing dementia risk in this population.