Health-related quality-of-life scales in Parkinson's disease: critique and recommendations.

Health-related quality of life is an important patient-reported outcome used in intervention trials and for monitoring the consequences of health status on physical, mental, and social domains. Parkinson's disease is a complex disorder that strongly affects patients' quality of life. Several health-related quality of life tools have been used in Parkinson's disease. A Movement Disorder Society Task Force was commissioned to rate the psychometric quality of available health-related quality of life scales as applied to Parkinson's disease. Following the methodology adopted by previous work of the Movement Disorder Society Task Force, a review of generic and specific health-related quality of life scales applied in studies on Parkinson's disease was completed. Considering the scales from 3 perspectives-use in Parkinson's disease, use by multiple research groups, and clinimetric properties-a final classification as "recommended," "suggested," or "listed" was applied to each reviewed instrument. Four generic scales (EuroQoL, Nottingham Health Profile, 36-Item Short-Form Health Survey, and Sickness Impact Profile) and 5 specific scales (39-Item Parkinson's Disease Questionnaire, Parkinson's Disease Questionnaire Short Form, Parkinson's Disease Quality of Life Questionnaire, Parkinson's Impact Scale, and Scales for Outcomes in Parkinson's Disease-Psychosocial) reached the level of "recommended." The 39-item Parkinson's Disease Questionnaire is the most thoroughly tested and applied questionnaire. Three other generic measures (Quality of Life Questionnaire 15D, Schedule for the Evaluation of Individual Quality of Life-Direct Weighting, and World Health Organization Quality of Life Assessment Short Version) and the specific Parkinson's Disease Quality of Life Scale are "suggested." With a little additional effort in completing the stipulated requirements, they could reach the "recommended" level. At present there is a wide variety of health-related quality of life measures for application in the Parkinson's disease setting, and the task force does not recommend the development of a new scale. Selection of the most appropriate instrument for a particular objective requires consideration of the characteristics of each scale and the goals of the assessment.

Immediate versus delayed switch from levodopa/carbidopa to levodopa/carbidopa/entacapone: effects on motor function and quality of life in patients with Parkinson's disease with end-of-dose wearing off.

OBJECTIVE: Assess motor function and quality of life (QoL) in Parkinson's disease (PD) subjects with end-of-dose wearing off (EODWO), comparing immediate and delayed switch (IS, DEL) to levodopa/carbidopa/entacapone (LCE). BACKGROUND: LCE treatment improves motor function in PD patients with EODWO. Correlations with QoL have not been previously assessed. METHODS: A 16-week, prospective, randomized, multicenter, open-label study in PD subjects on stable levodopa/carbidopa (LC) doses with EODWO. The IS subjects switched to LCE at baseline; DEL subjects at week 4. The primary efficacy variable was UPDRS III score (baseline to week 4). QoL measurements (PDQUALIF, PDQ-39) were assessed at baseline, weeks 4, 8, and study endpoint. RESULTS: The intent-to-treat population comprised 350/359 patients (IS, n = 177; DEL, n = 173). A significant decrease in UPDRS III scores at week 4 was observed (IS, 3.7U, p < .0001; DEL, 1.8U, p = .0018). Group differences favored IS (1.9U, p = .0148). At week 8, IS subjects had significant total score decreases in PDQUALIF (2.5U, p = .0133) and PDQ-39 (5.8U, p = .0001). In the mobility and activities of daily living PDQ-39 subdomains, IS subjects had significantly larger week 4 decreases (versus DEL p = .0331 and p = .0125, respectively). Adverse events included diarrhea (14.5%), nausea (12.3%), and dizziness (8.4%). CONCLUSION: The IS provided greater motor improvement at week 4 and improved QoL at week 8.

Pramipexole vs levodopa as initial treatment for Parkinson disease: a 4-year randomized controlled trial.

BACKGROUND: The best way to initiate dopaminergic therapy for early Parkinson disease remains unclear. OBJECTIVE: To compare initial treatment with pramipexole vs levodopa in early Parkinson disease, followed by levodopa supplementation, with respect to the development of dopaminergic motor complications, other adverse events, and functional and quality-of-life outcomes. DESIGN: Multicenter, parallel-group, double-blind, randomized controlled trial. SETTING: Academic movement disorders clinics at 22 sites in the United States and Canada. PATIENTS: Patients with early Parkinson disease (N = 301) who required dopaminergic therapy to treat emerging disability, enrolled between October 1996 and August 1997 and observed until August 2001. INTERVENTION: Subjects were randomly assigned to receive 0.5 mg of pramipexole 3 times per day with levodopa placebo (n = 151) or 25/100 mg of carbidopa/levodopa 3 times per day with pramipexole placebo (n = 150). Dosage was escalated during the first 10 weeks for patients with ongoing disability. Thereafter, investigators were permitted to add open-label levodopa or other antiparkinsonian medications to treat ongoing or emerging disability. MAIN OUTCOME MEASURES: Time to the first occurrence of dopaminergic complications: wearing off, dyskinesias, on-off fluctuations, and freezing; changes in the Unified Parkinson's Disease Rating Scale and quality-of-life scales; and adverse events. RESULTS: Initial pramipexole treatment resulted in a significant reduction in the risk of developing dyskinesias (24.5% vs 54%; hazard ratio, 0.37; 95% confidence interval [CI], 0.25-0.56; P<.001) and wearing off (47% vs 62.7%; hazard ratio, 0.68; 95% CI, 0.49-0.63; P =.02). Initial levodopa treatment resulted in a significant reduction in the risk of freezing (25.3% vs 37.1%; hazard ratio, 1.7; 95% CI, 1.11-2.59; P =.01). By 48 months, the occurrence of disabling dyskinesias was uncommon and did not significantly differ between the 2 groups. The mean improvement in the total Unified Parkinson's Disease Rating Scale score from baseline to 48 months was greater in the levodopa group than in the pramipexole group (2 +/- 15.4 points vs -3.2 +/- 17.3 points, P =.003). Somnolence (36% vs 21%, P =.005) and edema (42% vs 15%, P<.001) were more common in pramipexole-treated subjects than in levodopa-treated subjects. Mean changes in quality-of-life scores did not differ between the groups. CONCLUSIONS: Initial treatment with pramipexole resulted in lower incidences of dyskinesias and wearing off compared with initial treatment with levodopa. Initial treatment with levodopa resulted in lower incidences of freezing, somnolence, and edema and provided for better symptomatic control, as measured by the Unified Parkinson's Disease Rating Scale, compared with initial treatment with pramipexole. Both options resulted in similar quality of life. Levodopa and pramipexole both appear to be reasonable options as initial dopaminergic therapy for Parkinson disease, but they are associated with different efficacy and adverse-effect profiles.

Complete ascertainment of Parkinson disease in the Swedish Twin Registry.

This report describes the ascertainment of Parkinson disease (PD) in all individuals aged 50 years or older (49,814 individuals) from the Swedish Twin Registry. In phase one of the study, all twins were screened for PD using telephone interviews, with a response rate of 72.7%. In phase two, twins with suspected PD were re-contacted to exclude anyone from follow-up who reported parkinsonian symptoms due to diseases other than PD. In the third phase, in-person clinical evaluations were completed for twins who were still considered PD suspects after phase two and for a sample of co-twins. During the clinical evaluations, we also collected blood samples and information about a variety of environmental exposures. Overall prevalence rate for PD was 496 per 100,000 individuals. Among the 132 PD cases identified, there were only three concordant twin pairs. In total 7.2% of PD cases reported a first degree relative with PD.

Development and testing of the Parkinson's disease quality of life scale.

We report on the development and results of preliminary psychometric testing of a disease specific health-related quality of life (HRQoL) scale intended for use in individuals diagnosed with idiopathic Parkinson's disease (PD). Results from an initial qualitative study provided content for item development and scale construction of the Parkinson's disease quality of life scale (PDQUALIF). The 33-item instrument includes seven domains: social/role function, self-image/sexuality, sleep, outlook, physical function, independence, and urinary function, plus one item of Global HRQoL. Initial psychometric testing of the instrument was conducted in 233 outpatient clinic attendees with physician-confirmed idiopathic PD. Factor structure, reliability and validity of the scale have been established in this cross-sectional study. Continuing development of the PDQUALIF will be directed at enhancing the psychometric properties, establishing responsiveness and determining appropriateness in culturally diverse samples.