Sleep quality is associated with the severity of clinical symptoms in Parkinson's disease.

Sleep disorders are very common in Parkinson's disease (PD), being associated with several other conditions, mainly psychiatric disorders. The present study was designed to assess sleep quality in Brazilian patients with PD and to evaluate whether sleep changes are associated with clinical variables, especially neuropsychiatric symptoms in PD. Patients diagnosed with PD were subjected to a comprehensive clinical evaluation that included the assessment of motor, cognitive and psychiatric symptoms. Our study showed that sleep complaints are frequent in PD and worse sleep quality is associated with depressive and anxious symptoms, poorer cognitive performance and greater severity of PD symptoms. In the multivariate analysis, older age, greater severity of anxiety and PD remained as significant predictors of worse sleep quality. In conclusion, sleep complaints, depressive and anxiety symptoms are frequent in PD patients. Older age, disease severity and anxiety symptoms are significant predictors of poorer sleep quality in PD patients.