Impact of lower urinary tract symptoms/benign prostatic hyperplasia treatment with tamsulosin and solifenacin combination therapy on erectile function

Abstract

Purpose: To examine the effects on erectile function of concomitant treatment with an alpha-blocker (tamsulosin) and an antimuscarinic agent (solifenacin) in patients with lower urinary tract symptoms (LUTS)/benign prostatic hyperplasia (BPH).

Materials and methods: Fifty-seven male patients with LUTS/BPH were assessed for the degree of LUTS and erectile function. In group 1 (tamsulosin) and group 2 (tamsulosin and solifenacin), changes in the International Prostate Symptom Score [IPSS: total scores, storage symptoms (ST), voiding symptoms (VD), and quality of life (QoL)], prostate-specific antigen, trans-rectal ultrasonography, urine flowmetry, residual urine, and a 5-item version of the International Index of Erectile Function (IIEF-5) were assessed after a 3-month treatment period. In both groups, it was determined whether treatment was associated with changes in LUTS and erectile function and whether improvement in the IPSS was correlated with the IIEF-5. Comparative analysis was also done to examine the linear relationship between improved IPSS scores and IIEF-5 scores.

Results: A comparison of the degree of improvement in all the parameters indicated that both groups showed significant improvement in total IPSS, IPSS-ST, IPSS-VD, and IPSS-QoL (p<0.05). A comparison of the degree of improved sexual function associated with improved LUTS in each patient showed significant improvement in the IIEF-5 score associated with the degree of improvement in the IPSS-ST domain in group 1, but no significant associations were found in group 2. In cases in which tamsulosin was administered, the IIEF-5 score significantly improved as the IPSS-ST domain score improved. In the group in which tamsulosin and solifenacin were concomitantly administered, improvement of the IPSS-ST domain score had no significant effect on the IIEF-5 score.

Conclusions: In patients with LUTS/BPH, tamsulosin and solifenacin combination therapy was effective for LUTS, but erectile function was not significantly improved. Therefore, although effective for improving LUTS, combination therapy with an alpha-blocker and an antimuscarinic agent was not effective for improving erectile function.

Keywords: Prostatic hyperplasia; Sexual dysfunction, physiological; Solifenacin; Tamsulosin.

FIG. 1

Changes in IIEF-5 scores (IIEF-5) associated with improved IPSS-ST domain (IPSS-ST) in groups 1 and 2. In group 1 (tamsulosin solely administered), the storage (or irritative) symptom score (IPSS-ST) was significantly associated with erectile function (IIEF-5) depending on the degree of improvement (F=5.176, p=0.031; R²=0.16) (A). In group 2 (tamsulosin and solifenacin concomitantly administered), storage symptoms (IPSS-ST) showed no significant association with erectile function (IIEF-5) in relation to the degree of improvement (B). IIEF-5: International Index of Erectile Function-5, IPSS-ST: IPSS storage domain.