Sleep disorders are significant problem in hemodialysis patients, contributing to psychosocial disability and decline in qualiy of life. Aim of this study was to assess the quality of sleep disorders in relation to various clinical and sociodemographic factors in patients undergoing hemodialysis.

The preliminary study group included 55 persons selected at random from 150 patients treated by hemodialysis. The mean age was 60,31±12,14, mean time of dialysis 3,49 ± 4,53 years. 20 women and 35 men were interviewed using the Schedule for Clinical Assessment in Neuropsychiatry (SCAN) sleep disorders section and additional sociodemographic interview. In each case psychiatric examination has been performed. Medical comorbidity including restless legs syndrome (RLS), suffering from pain, blood and urine tests were analyzed for potential impact on sleep disturbance.

In studied group sleep disturbences did not show significant correlation with presence of mental disorders, somatic comorbidity other than RLS or most laboratory data (blood or urine tests). The following differences were observed:

1. 1. Positive correlation between overall sleep impairment, night wakefulness and nPCR index related to nutrition and metabolism (p-value 0.047),

2. 2. Greater sleep satisfaction in the group with higher calcium level before hemodialysis (p-value 0.045),

3. 3. Higher nightmares occurence in the group with lower calcium level before hemodialysis (p-value 0.023).

In the population of patients with end-stage renal disease after adaptation period to hemodialysis more important role in sleep disorders may play factors related to the somatic state and metabolism rather than psychiatric comorbidity.