Health related quality of life in Parkinson's disease: a prospective longitudinal study.

OBJECTIVES To examine the change over time in health related quality of life (HRQL) in a community based cohort of patients with Parkinson's disease. METHODS One hundred and eleven patients were evaluated for HRQL in 1993 and then again in a follow up study 4 years later. The patients included in the study in 1993 were derived from a prevalence study of patients with Parkinson's disease in the county of Rogaland, Norway. The HRQL was measured by the Nottingham health profile (NHP). At both evaluations clinical and demographic variables were determined during semistructured interviews and by clinical examinations by a neurologist. RESULTS During the 4 year follow up period there was a significant increase in NHP scores, reflecting a decreased HRQL, in the dimensions of physical mobility, emotional reactions, pain, and social isolation. In the same time period mean total NHP score increased from 120.0 (SD 102.6) to 176.0 (SD 119.4) (p<0.01). There were no clinical or demographic factors found in 1993 that identified patients at higher risk for developing decreased HRQL. Increased UPDRS score (unified Parkinson's disease rating scale) and Hoehn and Yahr stage during the 4 year study period correlated with increased NHP scores. Even though there was no increase in depressive symptoms or self reported insomnia, these symptoms, together with lower Schwab and England score, were the most important factors for a poor HRQL in 1997. CONCLUSIONS Parkinson's disease has a substantial impact on HRQL. Despite modern care, we found a significantly increased distress during the 4 year follow up period. Increased parkinsonism, measured by UPDRS and Hoehn and Yahr stage, correlated with increased stress, not only in the dimension of physical mobility, but also in the areas of pain, social isolation, and emotional reactions. In addition to the clinical examination, HRQL scoring provides valuable information on the total health burden of Parkinson's disease in both cross sectional and longitudinal evaluations, and contributes to a more comprehensive picture of the total disease impact.