Erectile dysfunction and disease-specific quality of life in patients with obstructive sleep apnea

Several reports have suggested a high incidence of erectile dysfunction (ED) among patients with obstructive sleep apnea syndrome (OSAS). The aim of this study was to investigate the correlation between OSAS and ED, or disease-specific quality of life (QOL) in patients with OSAS. In addition, we analyzed specific polysomnographic (PSG) parameters in predicting ED in OSAS patients. In total, 32 patients with OSAS and 27 normal controls were asked to complete the Korean versions of the International Index of Erectile Function questionnaire (KIIEF-5) and the Calgary Sleep Apnea Quality of Life Index (SAQLI). All patients then underwent a full-night in-laboratory PSG examination. Patients were diagnosed with OSAS if they had clinical symptoms suggestive of OSAS for at least 1 year and an apnea-hypopnea index (AHI) of more than 10 in PSG. Nineteen patients (59.3%) in the OSAS group showed ED, which was significantly higher than in the control group (8 patients, 29.6%, P=0.012). In addition, SAQLI scores worsened as AHI increased (r=0.327, P=0.011) and as the lowest oxygen saturation level decreased (r=0.420, P=0.001). ED was not significantly correlated with AHI (r=0.061, P=0.649); however, it was significantly correlated with the lowest oxygen saturation decreased (r=0.338, P=0.009). When the cutoff value for the lowest oxygen saturation level to predict ED was set at 77%, its positive predictive value was 88.9% (sensitivity=0.70, specificity=0.62). Thus, all male patients with OSAS should be screened for erectile dysfunction and more comprehensive consultation is needed, especially, if their lowest oxygen saturation levels are below 77%.