[Therapeutic effect of tadalafil on lower urinary tract symptoms with erectile dysfunction]

To investigate the therapeutic effect of low-dose tadalafil on BPH-induced lower urinary tract symptoms (LUTS) complicated with ED.

We randomly assigned 126 patients with BPH-induced LUTS and ED to receive daily administration of tadalafil (5 mg) plus tamsulosin hydrochloride sustained-release capsules (0.2 mg) (treatment group Ⅰ ［T-Ⅰ］, n = 42), tadalafil (5 mg) only (treatment group Ⅱ ［T-Ⅱ］, n = 42) or placebo (control group, n = 42), all for 12 weeks. Before and after 6 and 12 weeks of medication, and at 4 and 8 weeks after drug withdrawal, we recorded and compared the IPSS sub-item scores in the voiding stage and urinary storage symptoms, total IPSS, IIEF-5 scores, and the frequency of sexual activities among the three groups of patients.

As for the IPSS sub-item scores in the voiding stage symptoms, T-Ⅰ showed statistically significant differences between any two of the five time points (P < 0.05), but not T-Ⅱ between the baseline and 6-week medication or 8-week withdrawal (P > 0.05), or between 6-week medication and 8-week withdrawal (P > 0.05), nor did the control group among the five time points (P > 0.05). Statistically significant differences were observed between any two of the three groups at 12 weeks of medication and 4 weeks after drug withdrawal (P < 0.05), but not between the T-Ⅱ and control groups at 6 weeks of medication or 8 weeks after withdrawal (P > 0.05). As to the IPSS sub-item scores in the urinary storage symptoms, there were significant differences between any two time points in T-Ⅰ and T-Ⅱ (P < 0.05), but not in the control (P > 0.05), nor between T-Ⅰ and T-Ⅱ at 6 or 12 weeks of medication or at 4 or 8 weeks after drug withdrawal (P > 0.05). With regard to the total IPSS, statistically significant differences were found between any two of the three groups at 6 and 12 weeks of medication and 4 and 8 weeks after drug withdrawal (P < 0.05), but not between 6-week medication and 8-week withdrawal in T-Ⅰ or T-Ⅱ (P > 0.05), nor among the five time points in the control group (P > 0.05). Concerning the IIEF-5 scores, there was no significant difference in the frequency of sexual activities between the three groups （Ｐ>0.05）.There were statistically significant differences between any two of the three groups at 6 weeks of medication and 8 weeks after drug withdrawal (Ｐ<0.05), but not between 6-week medication and 4- or 8-week withdrawal (P > 0.05) or between 4- and 8-week withdrawal (P > 0.05) in T-Ⅰ, nor between 6-week medication and 8-week withdrawal in T-Ⅱ (P > 0.05) or among the five time points in the control (P > 0.05), nor between T-Ⅰ and T-Ⅱ at 12 weeks of medication (P > 0.05) or 4 weeks after drug withdrawal (P > 0.05).

Daily administration of tadalafil at 5 mg can effectively improve the IPSS sub-item scores in the urinary storage symptoms and IIEF-5 scores, with a persistent effect after withdrawal similar to that of its combination with other drugs, and therefore can be recommended for the treatment of BPH-induced LUTS complicated with ED.