Sleep-apnea in patients with end-stage renal disease and objective results

Background: a high prevalence of sleep apnea syndrome (SAS) of 54% - 80% ha s been reported in patients with end-stage renal disease (ESRD). However, t hese studies were either done in highly selected small patient groups or wi thout objective data using questionnaires only. Patients and methods: We, t herefore, studied the prevalence of SAS in a large, unselected group of pat ients with ESRD. During a 6-month period 77 out of 84 unselected patients w ith ESRD filled out the sleep apnea questionnaire of the University of Marb urg and the Epworth Sleepiness Scale. In 55 of these patients, snoring soun ds, heart rate, body position and transcapillary arterial oxygen saturation were recorded with an ambulatory device during the night after hemodialysi s. Results: In the questionnaires, 70.3% of the patients reported of an exc essive day-time sleepiness, 40.5% of unwillingly falling asleep during the day-time and 35.2% rated their ability to concentrate as decreased. 30.9% ( 40% male/15% female) of the patients showed evidence of sleep-disordered br eathing with an apnea-hypopnea-index (AHI) equal or more than 5/hour. 16.4% (20% male/10% female) of the patients met the diagnostic criteria of SAS. N either dialysis and biochemical data nor anamnestic parameters measured by the questionnaires correlated significantly with sleep-disordered breathing . Conclusion: The prevalence of SAS in this large unselected patient group tvas not as high as previously reported, but it is still considerably highe r than in the general population. Objective recordings are essential, as qu estionnaires overestimate the prevalence of SAS in patients with ESRD. As S AS promotes hypertension and impairs quality of life, ESRD patients might b enefit from a treatment of concomitant SAS.