Quality of sleep in patients with Parkinson's disease

Parkinson's disease (PD) is a progressive neurodegenerative disorder causing motor and non-motor symptoms. The latter are common and include autonomic dysfunction, cognitive impairment, and sleep difficulties. Many of the non-motor aspects of PD such as sleep disturbance are more common and significantly affect the day-to-day activities of patients and their quality of life. The most important aim of this study was to evaluate the sleep quality in patients with PD.

This case-control study was performed on patients with PD referred to the Neurology Clinic of our teaching hospital in 2011. Thirty-four patients with PD and 34 healthy people as control group were enrolled in this study. Sleep quality of patients and control was evaluated by Parkinson's disease sleep scale (PDSS) questionnaire. PDSS is a reliable and valid tool to measure sleep disorders in PD.

The mean total PDSS score in patient group was 55.29 (SD = 26.92) indicating moderate to severe sleep disturbances whereas, the mean total score in control group was 20.34 (SD = 10.65). Difference between the two groups' mean scores was significant (P < 0.05).

Our study demonstrated that patients with PD experienced poorer nocturnal sleep quality than the control group.