Objective: To evaluate the safety and efficacy of sildenafil citrate for treating erectile dysfunction (ED) in patients with combat-related post-traumatic stress disorder (PTSD).
Patients and methods: In all, 266 combat-exposed war veterans with ED (aged 37-59 years) were recruited. They met the Diagnostic and Statistical Manual of Mental Disorders-IV criteria for PTSD according to the Structured Clinical Interview for Patients, Investigator Version. The patients were also evaluated with the Clinician-Administered PTSD Scale, both to establish the diagnosis of PTSD and to measure symptom severity. Only patients with psychogenic ED were included in the study. Patients with comorbid conditions (diabetes mellitus, hypercholesterolaemia, hypertension, Peyronie's disease) and smokers of more than five cigarettes daily were excluded. The patients were randomly divided into a group of 133 who received 100 mg of on-demand sildenafil 0.75-2 h before sexual stimulation, and 133 who received placebo. Patients were asked to use > or =16 doses or attempts at home. The efficacy of the treatments was assessed every four attempts during treatment, and at the end of the study, using responses to the 15-question International Index of Erectile Function (IIEF), Sexual Encounter Profile diary questions 2 and 3, Erectile Dysfunction Inventory of Treatment Satisfaction questionnaire, patients' event logs of sexual activity, and a Global Assessment Question about erections.
Results: Sildenafil did not produce significantly and substantially greater improvement than placebo in each of the primary and secondary outcome measures (P = 0.08). A normal EF domain score (> or =26) at endpoint was reported by 13 (9.8%), and 11 (8.3%) of patients on the sildenafil and placebo regimens, respectively (P = 0.09). Patients treated with sildenafil had no statistically significantly greater improvement in the five sexual function domains of the IIEF questionnaire than those treated with placebo (P = 0.08). The incidences of treatment-emergent adverse events were significantly greater in the sildenafil arm than in the placebo group (P = 0.01).
Conclusions: Sildenafil is no better than placebo in treating PTSD-emergent ED. Further randomized clinical trials are warranted in combat veterans and other populations with PTSD to better elucidate the role of phosphodiesterase type 5 inhibitors in treating PTSD-emergent ED.