RESUMEN
INTRODUCTION: For men with erectile dysfunction (ED), the expectation of difficulty and level of confidence in achieving and maintaining an erection have an impact on sexual performance. OBJECTIVE AND METHODS: This 12-week, double-blind study investigated once-daily tadalafil (2.5 mg titrated to 5 mg or 5 mg) (n = 176) or placebo (n = 79) on confidence and perceived difficulty in performing sexual intercourse in men with ED who were incomplete responders to as-needed phosphodiesterase-5 inhibitor therapy. The Confidence in Performing Sexual Intercourse Questionnaire (CPSIQ) and Difficulty in Performing Sexual Intercourse Questionnaire (DPSIQ) were administered at baseline and 12 weeks. RESULTS: The mean change in CPSIQ for the tadalafil group was 1.8, which represents a shift from 'very low' to 'moderate' sexual confidence vs. a mean change of 0.5 in the placebo group (p < 0.0001). The mean change in DPSIQ for tadalafil was 1.6, which represents a shift from 'very difficult' to 'moderately' or 'slightly difficult' sexual performance vs. a mean change of 0.4 in the placebo group (p < 0.0001). Among men receiving tadalafil with an International Index of Erectile Function-Erectile Function (IIEF-EF) end-point score of ≥ 26 or who achieved a minimal clinically important difference in IIEF-EF score at end-point, the mean changes in CPSIQ were 3.0 and 2.4, respectively (both p < 0.0001). CONCLUSION: Once-daily tadalafil vs. placebo improves confidence and decreases difficulty in performing sexual intercourse for men with ED who were incomplete responders to as-needed PDE5 inhibitor therapy.