A recent study demonstrated that use of tamsulosin increased the risk of dementia in benign prostate hyperplasia(BPH)  patients. However, this study had a number of limitations. We evaluated the association between alpha-blockers and dementia in patients with benign prostate hyperplasia.

From the National Health Insurance Service database, we collected and analyzed data pertaining to alpha-blockers and dementia in the entire Korean adult population with BPH between January 2011 and December 2011. These patients were followed up until September 2017. We tested the effect of alpha-blockers on the risk of dementia using propensity score-matched Cox proportional hazard regression models and Kaplan-Meier survival analysis.

During a mean follow-up period of 1,580 (± 674.3) days, all inclusion and exclusion criteria were met by 59,472 patients with benign prostate hyperplasia. In the unadjusted cohort, the incidence of dementia in the tamsulosin, doxazosin, terazosin, alfuzosin, and no-medication cohorts were 17.96%, 18.55%, 20.64%, 17.62%, and 22.60%, respectively. After propensity score matching, the risk of dementia did not significantly differ between the tamsulosin cohort and the doxazosin [1.038 (0.960–1.121)] or alfuzosin [1.008 (0.925–1.098)] cohorts. The terazosin [1.112 (1.052–1.196)] cohort had a higher risk of dementia than the tamsulosin cohort. However, the risk of dementia was significantly lower in the terazosin cohort than in the no-medication cohort.

In this nationwide population-based study we found that alpha-blockers were not correlated with the risk of dementia in patients with BPH. Tamsulosin in particular did not affect the risk of developing dementia; these findings contradict those of a previous study [1]. Beyond simply not being associated with dementia, our results indicate that administering BPH medication lowers the risk of dementia in patients with BPH. The difference in these results may be due to various factors. First, it should be noted that the current study period was relatively long compared to that of the previous study (56.43 vs 19.8 months). However, as previous researchers have pointed out, the follow-up periods of previous studies were likely too short to observe the development of dementia, and may in fact represent an accelerated time to diagnosis [2]. Secondly, the mean age of the patients enrolled in this study is higher than that of previous studies (76.1–76.7 years vs 73.3–74.7 years). Indeed, age was found to be the strongest variable in the risk of dementia in all comparisons with our cohort study. However, age did not significantly affect the association between tamsulosin use and dementia risk in almost all analyses in a previous study [1]. With regard to previous findings indicating that age is associated with dementia, the current results indicate that our study cohort was representative of the general population. Moreover, we found that alpha-blockers, including tamsulosin, could lower the risk of dementia in patients with BPH. This may be explained by the following hypothesis: the no medication group in this study is not representative of the general elderly population. That is, the no medication group is likely to comprise untreated patients with BPH. Therefore, this finding should not be misinterpreted to mean that BPH medication lowers the risk of dementia in healthy individuals.

The findings of this large population-based study indicate that the use of BPH medication is not associated with an increased risk of dementia overall, by duration of use, or by medication type. Further well-designed, prospective studies are warranted to validate our findings.

Duan, Y., Grady, J. J., Albertsen, P. C. et al.: Tamsulosin and the risk of dementia in older men with benign prostatic hyperplasia. Pharmacoepidemiol Drug Saf, 27: 340, 2018
Madersbacher, S., Michel, M. C.: Re: Tamsulosin and the Risk of Dementia in Older Men with Benign Prostatic Hyperplasia. Eur Urol, 2018