Urinary Incontinence in Alzheimer's Disease: A Population-Based Cohort Study in Taiwan

Objectives: Urinary incontinence (UI) is more prevalent in the elderly populations with dementia than without dementia, and Alzheimer's disease (AD) is the most common cause of dementia. Urinary incontinence may complicate AD morbidity and mortality. Therefore, this study aimed to evaluate the prevalence and annual incidence and determine the risk possibility of UI, which is the main type of incontinence in patients with AD in Taiwan. Methods: A total of 933 patients with AD were included in the study cohort, and a total of 2799 patients without AD by 1:3 proportion compared to the study cohort were used as a matched cohort. All participants were selected from the National Health Insurance Research Database in 2000 sample population. We utilize Cox proportional hazard regression to evaluate the risk of UI and cumulative incidence ratio curve to analyze the cumulative incidence function. Prevalence and annual incidence rate are calculated in individual medication including rivastigmine, donepezil, galantamine, and memantine only being initiated in patients with AD. Results: The risk of UI is higher in AD cohort (hazard ratio: 1.54, 95% confidence interval: 1.13-2.09). The cumulative incidence ratio of UI event between AD cohort and matched cohort presents statistical significance (P <.001). Annual incidence and prevalence of UI in patients with AD are 6.2% and 4.2%, respectively. Conclusion: The present results suggest that the risk of UI is higher in patients with AD than in the general population.