Sleep Quality And The Risk Of Sleep Apnea In Patients On Chronic Hemodialysis

Background. A problem of sleep disorders in chronic hemodialysis (HD) patients has been only scarcely studied. Objectives. To assess quality of sleep and risk of sleep apnea in HD patients.Material and methods. Two surveys assessing sleep quality and risk of sleep apnea, i.e. Berlin Questionnaire (BQ) and Epworth Sleepiness Scale (ESS) were conducted among 126 HD patients (44 F, 82 M, age 60.2 +/- 13.1 years). The results were correlated to anthropometric indices, comorbidities, length of hemodialysis session, dialysis shift and weekly interdialytic weight gain.Results. Mean body mass index (BMI) of HD patients was 26.1 +/- 4.1 kg/m(2), exceeding 25 kg/m(2) in 68 patients (54.4%) including 26 with > 30 kg/m2. 71% of patients were hypertensive. HD patients slept on average 7.6 hours daily. 47% declared sleeping problems. 53 patients (42%) had high probability of sleep apnea (BQ score >= 2), in particular those with arterial hypertension (44 patients). 28% of patients slept very badly (SSE class 3), 79% reported waking up at night and 48% snoring. Risk of sleep apnea was greatest among those dialyzed in the morning (13% vs 8% in the afternoon and 10% at night for BQ and 13% vs 10% in the afternoon and 5% at night for ESS). Interdialytic body weight gain did not affect the risk of sleep apnea.Conclusions. The risk of sleep apnea among HD patients depends on BMI and degree of overhydration. The scales commonly used in general population require validation in HD patients.