Severe obstructive sleep apnoea syndrome and erectile dysfunction: a prospective randomised study to compare sildenafil vs. nasal continuous positive airway pressure

Background: A high incidence of erectile dysfunction (ED) among patients with obstructive sleep apnoea syndrome (OSAS) has been reported, with a strong correlation between obstructive sleep apnoea, ED, and quality of life (QOL), and it has been estimated that 10-60% of patients with OSAS suffer from ED. In this prospective randomised controlled trial, we investigated 82 men with ED consecutively who were referred to the outpatient clinic for sleep disorders and had severe OSAS (AHI> 30 events/h) without any other comorbidities as a possible cause of ED. The aim of this study was to evaluate and compare the efficacy of sildenafil vs. continuous positive airway pressure (CPAP) in men with ED and severe OSAS. Methods: Eighty-two patients were randomised to two main treatment groups: group 1 patients (n = 41) were treated with 100-mg sildenafil 1 h before sexual intercourse without CPAP, and group 2 patients (n = 41 men) were treated with only nasal CPAP during night time sleep. Both groups were evaluated with the same questionnaires (International Index of Erectile Function-EF domain; Sex Encounter Profile; Erectile Dysfunction Inventory Treatment Satisfaction) 12 weeks after treatment. Results: In patients receiving sildenafil treatment, 58.2% of those who attempted sexual intercourses were successful compared to 30.4% in the CPAP group. The mean number of successful attempts per week was significantly higher in the sildenafil group compared with the CPAP group (2.9 vs. 1.7, respectively; p < 0.0001). The mean IIEF-EF domain scores were significantly higher in the sildenafil group compared with the CPAP group (p < 0.0001). The overall satisfaction rate was 68% with sildenafil treatment and 29% with CPAP treatment. Conclusions: This study confirms that severe OSAS is strongly associated with erectile dysfunction. CPAP and sildenafil (100 mg) are safe and effective therapies for OSAS-related ED patients. In the present study sildenafil was more effective than CPAP in treating ED associated with OSAS, as indicated by a significantly higher rate of successful attempts at intercourse and higher IIEF-EF domain scores. Our study, to date, is the only that has investigated sildenafil in patients with severe OSAS.