Ten-year follow-up of sildenafil use in spinal cord-injured patients with erectile dysfunction

Data are sparse concerning the long-term effects of phosphodiesterase type 5 (PDE5) inhibitors for erectile dysfunction (ED).

To evaluate the efficacy and safety of long-term sildenafil use in subjects with ED caused by spinal cord injury (SCI).

Phase 1: From October 1998 to January 1999, 113 SCI patients with ED were given 50 mg of sildenafil after a 4-week treatment-free period. Those with a score lower than 26 on the International Index of Erectile Function (IIEF-15) and with less than 75% total successful sexual attempts the dosage of sildenafil was increased to 100 mg. Attempts were evaluated using the Sexual Encounter Profile Questions 2 and 3 (SEP2 and 3) regarding respectively the capacity to penetrate their partner and to maintain the erection after penetration. Phase 2: Only responding patients entered phase 2 where they were evaluated every 6 months. The final visit was concluded by January 2009.

Follow-up using the IIEF-15 questionnaire every 6 months.

Seventy-five patients entered Phase 2. Thirty-eight patients were excluded, 35 of them because they did not respond to the drug. Lesions higher than T12, an incompleteness of lesions, and higher residual erection were significant predictable factors for the success of the therapy (P < 0.05). Phase 2: the most frequent reason (68.3%) for discontinuing treatment was the desire to try a new oral therapy especially for patients using 100 mg. Thirty-four individuals continued treatment, 28 of whom took 50 mg.

Sildenafil represents an effective and safe long-term option for SCI subjects with ED. Further investigation of long-term use of oral PDE5 inhibitors in SCI patients is needed for evaluating both factors that are determinant in the choice of a starter treatment and in detecting elements that influence the switching from initial treatment.