Association between α1-adrenoceptor antagonists and delirium: Analysis of the Japanese Adverse Event Report database

Abstract

Abstract Background: Tamsulosin, an α1-adrenoceptor antagonist, may increase the risk of dementia in older men with benign prostatic hyperplasia. An association between α1-adrenoceptor antagonists and delirium has been suggested, but the details are unclear. Aims: This study investigated the association between α1-adrenoceptor antagonists and delirium in patients with benign prostatic hyperplasia, using the Japanese Adverse Drug Event Report database. Method: First, disproportionality analysis compared the frequency of delirium in the α1-adrenoceptor antagonists silodosin, tamsulosin, and naftopidil. Next, multivariate logistic analysis was performed to examine the association between delirium and α1-adrenoceptor antagonists where disproportionality was detected. Results: A disproportionality in delirium was observed in patients who received tamsulosin (reporting odds ratio 1.85, 95% confidence interval 1.38–2.44, P < 0.01) and naftopidil (reporting odds ratio 2.23, 95% confidence interval 1.45–3.28, P < 0.01). Multivariate logistic analysis revealed that in addition to previously reported risk factors for delirium, delirium in patients who received tamsulosin was significantly increased with concomitant use of anticholinergics (odds ratio 2.73, 95% confidence interval 1.41–5.29, P < 0.01) and delirium in patients who received naftopidil was significantly increased with concomitant use of β3 adrenoceptor agonists (odds ratio 4.19, 95% confidence interval 1.66–10.6, P < 0.01). Conclusion: We found that concomitant use of anticholinergic or β3 adrenoceptor agonistsused to treat overactive bladder were strongly associated with delirium. Therefore, confirming the medical history and concomitant medications of patients who receive tamsulosin or naftopidil and providing preventive interventions for delirium may contribute to improved patient outcomes.