Insomnia and depressive symptoms in patients with Parkinson's disease. Relationship to health-related quality of life. An interview study of patients living at home.

The objectives of this study were to describe the prevalence of insomnia and depressive symptoms in patients with Parkinson's disease (PD) and to relate those symptoms to health-related quality of life. A total of 102 patients living at home, most of them moderately to severely disabled, were interviewed. Of them 43 patients were women with a mean age of 70 (range 58-79). The mean age for the men was 71 (range 56-80). Time since diagnosis was <2 years for 57%, 2-10 years for 31% and >10 years for 12%. The geriatric depression scale (GDS) and Livingston's insomnia scale were used. The results were related to quality of life as measured with the SF-36 health survey. The prevalence of insomnia was 80%. Moderate depressive symptoms were found in 47% and severe depressive symptoms in 5%. Patients with insomnia or with depressive symptoms had a significantly impaired quality of life on all eight scales of the SF-36. In a stepwise regression analysis the presence of pain and ache and depressive symptoms were significantly related to insomnia. The variables most related to depressive symptoms were Hoehn and Yahr group and insomnia. Hoehn and Yahr groups (more disability) were significantly related to insomnia and depressive symptoms. Thus, insomnia and depressive symptoms are prevalent in PD and influence quality of life and should, therefore, be considered when evaluating patients with PD.