Context Erectile dysfunction is common in men with diabetes.
Objective To assess the efficacy and safety of oral sildenafil
citrate in the treatment of erectile dysfunction in men with diabetes.
Design A multicenter, randomized, double-blind,
placebo-controlled, flexible dose-escalation study conducted May
through November 1996.
Setting Patients' homes and 19 clinical practice centers in the
Patients A total of 268 men (mean age, 57 years) with erectile
dysfunction (mean duration, 5.6 years) and diabetes (mean duration, 12
Interventions Patients were randomized to receive sildenafil
(n=136) or placebo (n=132) as needed,
but not more than once daily, for 12 weeks. Patients took the study
drug or placebo 1 hour before anticipated sexual activity. The starting
dose of sildenafil citrate was 50 mg, with the option to adjust the
dose to 100 mg or 25 mg based on efficacy and tolerability, to be taken
Main Outcome Measures Self-reported ability to achieve and
maintain an erection for sexual intercourse according to the
International Index of Erectile Function and adverse events.
Results Two hundred fifty-two patients (94%) completed the study
(131/136 in the sildenafil group, 121/132 in the placebo group). By
intention-to-treat analysis, at 12 weeks, 74 (56%) of 131 patients in
the sildenafil group reported improved erections compared with 13
(10%) of 127 patients in the placebo group (P<.001). The
proportion of men with at least 1 successful attempt at sexual
intercourse was 61% (71/117) for the sildenafil group vs 22% (25/114)
for the placebo group (P<.001). Adverse events related to
treatment were reported for 22 (16%) of 136 patients taking sildenafil
and 1 (1%) of 132 patients receiving placebo. The most common adverse
events were headache (11% sildenafil, 2% placebo), dyspepsia (9%
sildenafil, 0% placebo), and respiratory tract disorder (6%
sildenafil, 2% placebo), predominantly sinus congestion or drainage.
The incidence of cardiovascular adverse events was comparable for both
groups (3% sildenafil, 5% placebo).
Conclusion Oral sildenafil is an effective and well-tolerated
treatment for erectile dysfunction in men with diabetes.