Phosphodiesterase inhibitors in the treatment of erectile dysfunction in spinal cord-injured men

Abstract

Open, before-after study. To assess the efficacy and safety of phosphodiesterase type 5 (PDE5) inhibitors for erectile dysfunction (ED) in spinal cord-injured (SCI) patients. Home- and clinic-based assessments in the outpatient department at the Centre Bouffard Vercelli, Cerbère France. Clinic trials with Sildenafil (Viagra) on 120 patients, Tadalafil (Cialis) on 54 patients and Vardenafil (Levitra) on 66 patients were performed. Flexible doses of PDE5 inhibitors were given depending on efficacy and tolerability, from 50 to 100 mg for Sildenafil, and from 10 to 20 mg for Vardenafil and Tadalafil. Each trial was performed after a week's interval. The efficacy was self-assessed by the patients on a six-point quantitative scale assessment. The response to treatment was assessed at home in 90 patients (57 patients on Sildenafil, 12 patients on Vardenafil and 21 patients on Tadalafil) using the International Index of Erectile Function (IIEF). In clinic trials, PDE5 inhibitors were effective (rigidity enough for penetration) in 85% of the patients on Sildenafil, 74% of the patients on Vardenafil and 72% of the patients on Tadalafil. The mean duration of erection was 34, 28 and 26 min, respectively. Adverse effects were mild, usually attenuated with continued dosing. More than 70% of the patients on Vardenafil and Tadalafil required higher doses of 20 mg, whereas 50 mg of Sildenafil was effective in 55% of the patients. Two-thirds of our patients on Tadalafil reported a duration of action longer than 24 h. The presence of an upper motor neuron lesion was significantly associated with therapeutic success, lower motor neuron lesions and cauda equina patients were poor responders. Other variables such as completeness of lesion had no impact. In the follow-up visits, the IIEF global scores and three IIEF domains (erectile function, intercourse satisfaction and overall satisfaction) were significantly improved in all patients. Patients on Sildenafil showed a significant improvement of orgasmic function, ejaculation (Question 9) and orgasm (Question 10). Sildenafil, Vardenafil and Tadalafil are all effective and well-tolerated treatments for ED in SCI patients. Although no statistical analysis could be applied on these data, these results might indicate that Sildenafil is more effective in treating ED. Clinic trials are important for proper dose titration and appropriate education of the patients.