Effects of tadalafil versus silodosin on voiding function in male patients with non-neurogenic detrusor underactivity: A comparative study using propensity score matching.

OBJECTIVES

To investigate and compare the effects of tadalafil and silodosin on lower urinary tract symptoms and voiding functions in men with non-neurogenic detrusor underactivity.

METHODS

A total of 126 treatment-naive men with lower urinary tract symptoms diagnosed as non-neurogenic detrusor underactivity received tadalafil (5 mg/day) or silodosin (8 mg/day) for 12 months. After propensity score matching, parameter changes from before administration to 12 months since treatment initiation were assessed based on subjective symptoms and urodynamic findings, including bladder contractility index and maximum urinary flow rate, and were compared between the tadalafil treatment group and the silodosin group. Detrusor underactivity was defined as bladder contractility index <100 and bladder outlet obstruction index <40.

RESULTS

After propensity score matching, the final analysis included 48 patients each in the tadalafil and silodosin groups. No significant differences in prostate volume, subjective symptoms or urodynamic parameters were detected between the groups at baseline. Compared with baseline, significant improvements in subjective symptoms and storage and voiding functions were observed at month 12 in both groups. Maximum urinary flow rate significantly improved by 1.7 mL/s in the silodosin group and by 3.0 mL/s in the tadalafil group. In addition, the mean bladder contractility index increased from 80.0 to 86.1 in the silodosin group and from 77.9 to 97.6 in the tadalafil group. Improvements in maximum urinary flow rate and bladder contractility index were significantly superior in the tadalafil group.

CONCLUSIONS

Both tadalafil and silodosin significantly improve lower urinary tract symptoms and voiding function in patients with non-neurogenic detrusor underactivity. Furthermore, tadalafil is more effective than silodosin in improving bladder contractility index and maximum urinary flow rate.