Association Between Alpha-1 Adrenoreceptor Antagonist Use and Cognitive Impairment: A Systematic Review

Alpha-1 adrenergic receptor (α1-AR) antagonists are commonly used for management of benign prostatic hyperplasia or hypertension. Some studies have shown a potential link between α1-AR antagonist use and cognitive impairment. Given the conflicting data surrounding α1-AR antagonists association with cognitive dysfunction, we aim to systematically review the association of cognitive dysfunction with α1-AR antagonist use to aid clinician decision both with medication initiation and continuation. A systematic review was performed following PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines. We searched Ovid Cochrane, Ovid Embase, Ovid MEDLINE, Scopus, and Web of Science on March 7, 2023, with an update run on January 22, 2024. The primary outcome was cognitive dysfunction. We used Cochrane risk of bias for randomized controlled trials (RCTs) and MINORS (Methodological Index for Non-Randomized Studies) criteria for non-RCTs to evaluate study quality. This study was registered with PROSPERO (CRD42024505751). We identified 7 studies for our systematic review (3 RCTs, 4 non-RCTs). Tamsulosin was the most studied medication (6 of 7 studies). Tamsulosin was associated with no cognitive dysfunction in 2 RCTs, increased risk for dementia in 2 non-RCTs, no change in cognition in 1 non-RCT, and decreased risk for dementia in 1 non-RCT. Among 3 non-RCTs analyzing alfuzosin, it was associated with decreased risk of or no association with dementia in 2 studies and increased risk for dementia in 1 study. Doxazosin, prazosin, and terazosin were neutral or showed a negative risk for dementia. Our systematic review did not show a convincing causal association between α1-AR antagonists, including tamsulosin, and cognitive dysfunction. Considering the existing literature, it is appropriate to use α1-AR antagonists without concern for cognitive dysfunction. Future research, through robust study designs considering the multifactorial nature of cognitive dysfunction, is required to further evaluate this association.