Effect of improvement in lower urinary tract symptoms on sexual function in men: Tamsulosin monotherapy vs. combination therapy of tamsulosin and solifenacin

Purpose: To evaluate how much the improvement of lower urinary tract symptoms (LUTS) affects sexual function and which storage symptoms or voiding symptoms have the greatest effect on sexual function. Materials and Methods: A total of 187 patients were enrolled in this study. Patients were randomly assigned to receive either tamsulosin 0.2 mg (group A) or tamsulosin 0.2 mg and solifenacin 5 mg (group B). At 4 weeks and 12 weeks, the LUTS and sexual function of the patients were evaluated by use of the International Index of Erectile Function-5 (IIEF5), International Prostate Symptom Score (IPSS), Overactive Bladder Symptom Score (OABSS) questionnaire, uroflowmetry, and bladder scan. Results: Both groups A and B showed statistically significant improvements in IPSS, OABSS, and quality of life (QoL). Group A showed improved maximum flow rate, mean flow rate, and residual urine volume by time. Group B did not show an improvement in flow rate or residual urine volume but total voiding volume increased with time. The IIEF5 score was not improved in either group. In group A, the IIEF5 score dropped from 13.66±4.97 to 11.93±6.14 after 12 weeks (p=0.072). Group B showed a decline in the IIEF5 score from 13.19±5.91 to 12.45±6.38 (p=0.299). Although group B showed a relatively smaller decrease in the IIEF5 score, the difference between the two groups was not significant (p=0.696). Conclusions: Tamsulosin monotherapy and combination therapy with solifenacin did not improve erectile function despite improvements in voiding symptoms and QoL. The improvement in storage symptoms did not affect erectile function.