The SCOPA-COG is a short, reliable, and valid instrument that is sensitive to the specific cognitive deficits in PD.

Cognition is an important domain of the clinical spectrum of PD and poorer cognitive performance is associated with greater impairment in motor and non-motor domains in PD. The difference in cognitive scores between PIGD dominant patients and tremor dominant patients likely reflects more advanced disease.

Objective: To compare and contrast disease-specific quality of life instruments in Parkinson's disease and assess their clinimetric properties. Methods: Two reviewers independently evaluated both thoroughness and results of studies regarding clinimetric characteristics of identified scales. Results: Twenty studies were found reporting on the clinimetric properties of four scales. The content validity of the Parkinson's disease questionnaire-39 item version (PDQ-39), the Parkinson's disease quality of life questionnaire (PDQL), and the "Fragebogen Parkinson LebensQualität" (Parkinson Quality of Life questionnaire; PLQ) was adequate to good, but for the Parkinson's impact scale (PIMS) it was insufficient. Construct validity of both the PDQ-39 and the PDQL was good, but for the PLQ and the PIMS this was insufficiently evaluated. Internal consistency of all scale totals and of subscale totals of the PDQL were good, whereas for the social support subscale of the PDQ-39 and four subscales of the PLQ this was inadequate. Test-retest reliability was not evaluated for the PDQL and was adequate in the other scales. Responsiveness was partially established for the PDQ-39, and not assessed for the other scales. The number of available translations, as well as the number of studies in which these instruments were used, differed considerably. Conclusions: The selection of an instrument partially depends on the goal of the study. In many situations however, the PDQ-39 will probably be the most appropriate HRQoL instrument. The PDQL may be considered as an alternative, whereas the PLQ may be considered in studies involving German speaking patients with Parkinson's disease. Use of the PIMS should be considered only as a means of identifying areas of potential problems.

BACKGROUNDLevodopa is the main treatment for symptoms of Parkinson's disease. Determining whether levodopa also has a disease-modifying effect could provide guidance as to when in the course of the disease the treatment with this drug should be initiated. METHODSIn a multicenter, double-blind, placebo-controlled, delayed-start trial, we randomly assigned patients with early Parkinson's disease to receive levodopa (100 mg three times per day) in combination with carbidopa (25 mg three times per day) for 80 weeks (early-start group) or placebo for 40 weeks followed by levodopa in combination with carbidopa for 40 weeks (delayed-start group). The primary outcome was the between-group difference in the mean change from baseline to week 80 in the total score on the Unified Parkinson's Disease Rating Scale (UPDRS; scores range from 0 to 176, with higher scores signifying more severe disease). Secondary analyses included the progression of symptoms, as measured by the UPDRS score, between weeks 4 and 40 and the noninferiority of early initiation of treatment to delayed initiation between weeks 44 and 80, with a noninferiority margin of 0.055 points per week. RESULTS

The objective of this questionnaire-based survey was to evaluate the prevalence and causes of sleep disturbances in 90 nondepressive patients with Parkinson's disease (PD) and 71 age-matched healthy subjects. We also assessed the prevalence and characteristics of excessive daytime sleepiness (both groups) and excessive fatigue (PD patients). A high prevalence of sleep disturbances in PD patients was found; this is to a large extent probably the result of aging. As compared with controls, patients had a more severely disturbed sleep maintenance because of nycturia, pain, stiffness, and problems with turning in bed. The prevalence of excessive dreaming is similar in both groups, but altered dream experiences almost exclusively occurred in PD. Patients rated themselves more often to be morning-types than controls. This finding may account for the reported adaptation effects in experimental settings and the reduced REM latency in PD patients. The prevalence of daytime sleepiness was similar in both groups. Excessive daytime sleepiness showed a clear diurnal pattern with a peak in the early afternoon. As for excessive fatigue, the majority of the patients did not report a preferential time for this symptom. Our findings further argue against an association of fatigue with any circadian factor, and instead suggest a relationship with the motor deficits of PD.