Cumulative use of therapeutic bladder anticholinergics and the risk of dementia in patients with lower urinary tract symptoms: a nationwide 12-year cohort study.

BACKGROUND: Studies have shown an association between lower urinary tract symptoms (LUTS) and an increased risk of dementia. Whether anticholinergic use contributes to the development of dementia in patients with LUTS remains unknown, especially in Asian populations. This study aims to investigate the association between anticholinergic use and dementia in patients with LUTS. METHODS: This study included patients aged 50 years and over with newly diagnosed LUTS (January 2001 to December 2005), divided into four groups according to their cumulative defined daily doses (cDDDs) of anticholinergics: < 28 cDDDs, 28-84 cDDDs, 85-336 cDDDs, ≥337 cDDDs. Patients were followed up until dementia developed or until the end of 2012. RESULTS: We recruited a total of 16,412 patients. The incidence of dementia was 10% in the < 28 cDDD group, 8.9% in the 28-84 cDDD group, 11.5% in the 85-336 cDDD group, and 14.4% in the ≥337 cDDD group (p = .005). In a Cox proportional hazards analysis, the adjusted hazard ratio of dementia was 1.15 (95% CI = 0.97-1.37) in the 85-336 cDDD group, and 1.40 (95% CI = 1.12-1.75) in the ≥337 cDDD group after adjusting for covariates. CONCLUSIONS: Our study indicates that higher cumulative anticholinergic exposure is associated with an increase in the risk of incident dementia in patients with LUTS aged 50 years of age and over. Either using one anticholinergic agent or switching anticholinergic agents cumulatively increases this risk. Therapeutic risks and benefits of using anticholinergics in LUTS treatment should be clinically reviewed and weighed.