Antimuscarinic Use and Dementia Incidence in Women With Overactive Bladder

Antimuscarinic medications are widely used for overactive bladder (OAB). Recent studies linking antimuscarinics to dementia and cognitive impairment (DCI) have raised concerns about long-term antimuscarinic use for OAB management.

We sought to investigate the incidence of DCI among patients with OAB and whether DCI incidence is associated with antimuscarinic use.

We conducted a retrospective cohort study of women aged 55 years or older with OAB, without a preexisting DCI diagnosis, within a managed health care system with at least 10 years of follow-up. Participants were divided into 2 groups: antimuscarinic users and nonusers for OAB. We calculated each participant's total antimuscarinic burden and identified incident DCI using International Classification of Diseases codes. We used bivariate analysis to identify factors associated with DCI and multivariate logistic regression to assess the association between antimuscarinic use and DCI.

Of the 16,249 women included, 7,141 (44%) received antimuscarinics for OAB and 1,200 (7.4%) were diagnosed with DCI. Compared with those without DCI, women with DCI were older, less likely to be white, had more comorbidities, were more likely to use antimuscarinics, and had higher mean anticholinergic burden scores. Age at OAB diagnosis (OR: 1.13, CI: 1.12-1.14, P <0.001), diabetes (OR: 1.43, CI: 1.22-1.68, P <0.001), and bladder antimuscarinic use (OR: 1.27, CI: 1.12-1.44, P <0.001) were associated with incident DCI using multivariate analysis.

Among women with OAB, DCI is associated with bladder antimuscarinic use and with higher cumulative exposure to antimuscarinics. This association persists after controlling for age and comorbidities.