Associations between Anticholinergic Use and Dementia Risk in a Prevalent-User Cohort: Analysis of Japanese Medication Histories as Real-World Data

Medication history from Japanese pharmacies is potentially rich in useful information regarding drug-related events in diverse populations; however, this information has rarely been utilized as real-world data. This study aimed to evaluate the feasibility of using medication history as real-world data to assess associations between anticholinergic medications for overactive bladder (OAB) and increased risk of dementia. A retrospective prevalent-user cohort study was performed to analyze medication history using a logistic regression model. The primary exposure was anticholinergic drug use for OAB (vs. beta-3 agonists only). The risk associated with each specific anticholinergic drug was also analyzed. Adjustments included age, sex, comorbidities (diabetes, hyperlipidemia, and hypertension), and psychotropic drug use. OAB anticholinergics and age were significant predictors. The adjusted odds ratio (OR) and 95% confidence interval (CI) for OAB anticholinergics were 1.53 (95% CI: 1.10-2.14, p = 0.0110), and those for age were 1.07 (95% CI: 1.04-1.09, p < 0.0001). Among individual OAB anticholinergics, the ORs for oxybutynin (4.53; 95% CI: 2.18-9.42, p < 0.0001) and tolterodine (5.64; 95% CI: 2.42-13.17, p < 0.0001) were significant, whereas ORs for other OAB anticholinergics were not. These findings suggest the potential to identify agents with lower dementia risk. In conclusion, analysis in this prevalent-user cohort study using medication history data showed a significant association between OAB anticholinergic use and increased dementia risk, with variation by drug. These results support the feasibility of utilizing medication history as real-world data for pharmacovigilance.