**3. Related factors with sleep problems in hemodialysis patients**

A multitude of causes including anemia, blood urea levels, plasma creatinine levels, parathyroid hormone (PTH) concentrations, increased blood pressure, quality of life, and illness intrusiveness may contribute to sleep disturbances in patients on maintenance hemodialysis (Hanly et al., 2003; Iliescu et al., 2004; Sabbatini et al.,2003). Furthermore, there is a positive correlation between sleep disturbances and increased morbidity and mortality related to cardiovascular disease and infectious complications, the 2 major causes of death in hemodialysis patients (De Santo et al., 2005). Sleep disorders in hemodialysis patients is a multifactorial complaint, stemming from Uremic toxins and dialysis procedure, other medical problems, psychiatric or psychosocial background.
