Influence of clinical and demographic variables on quality of life in patients with Parkinson's disease

Objectives-To identify the clinical and demographic factors that are associ ated with a poor quality of life in patients with Parkinson's disease. Methods-233 of a total of 245 patients identified in a community based stud y in a Norwegian county participated in the study. Quality of life was meas ured by the Nottingham Health Profile (NHP). The results were compared with those in 100 healthy elderly people. Clinical and demographic variables we re determined during a semistructured interview and by clinical examination by a neurologist. Multiple regression analyses were used to determine whic h variables were associated with higher distress scores. Results-Patients with Parkinson's disease had higher distress scores than t he healthy elderly people for all the NHP dimensions. The variables that mo st strongly predicted a high total NHP score were depressive symptoms, self reported insomnia, and a low degree of independence, measured by the Schwa b acid England scale. Severity of parkinsonism contributed, but to a lesser extent. Nearly half the patients with Parkinson's disease reported lack of energy, compared with a fifth of the control group. Severity of depressive symptoms and a higher score on the UPDRS motor subscale only partly accoun ted for this finding. Only 30% of the variation in NHP energy score was exp lained by the predictive variables identified in this study. Conclusions-Parkinson's disease has a substantial impact on health related quality of life. Depressive symptoms and sleep disorders correlated strongl y with high distress scores. Patients with Parkinson's disease should be ex amined for both conditions, which require treatment. Low energy was commonl y reported and may be a separate entity of Parkinson's disease.