Background:Sleep disturbances are common among uremic patients; however, limited data are available on predictors of sleep quality in this population. We assessed sleep quality in patients on hemodialysis (HD) and peritoneal dialysis (PD) and investigated predictors related to sleep quality.Methods:Patients on maintenance HD and PD were consecutively included from two medical centers in Isfahan city (Iran). They completed the Pittsburgh sleep quality index (PSQI) and hospital anxiety and depression scale. Laboratory tests were done for iron state, kidney function, and electrolytes. Univariate and multivariate analyses were performed to find predictors of sleep quality.Results:About 90 patients were evaluated (53 males, age = 54.2 ± 15.2 years, disease duration = 5.3 ± 4.5 years). Poor sleep quality was frequent in 86.6% of the cases in each group of HD and PD patients. Patients on HD had poorer sleep quality in terms of total PSQI scores and two dimensions of sleep latency and sleep efficiency (P < 0.05). Anxiety (β = 0.232, P = 0.027), depression (β = 0.317, P = 0.004), and being on HD (β = 2.095, P = 0.009) were independent predictors of overall poor sleep quality.Conclusions:Poor sleep quality is highly frequent in patients on maintenance dialysis and mood disorders and being on HD are predictive factors. Further studies are required for better understanding of risk factors associated with poor sleep quality and thus possible treatments in these patients.