Efectividad del 123I-ioflupano (DaTSCAN©) en el diagnóstico de síndromes parkinsonianos. Una revisión sistemática

The best way to initiate dopaminergic therapy for early Parkinson disease remains unclear. 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. Multicenter, parallel-group, double-blind, randomized controlled trial. Academic movement disorders clinics at 22 sites in the United States and Canada. 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. 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. 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. 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. 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.

Vascular parkinsonism (VP) is difficult to diagnose with any degree of clinical certainty. We investigated the importance of macroscopic cerebral infarcts and pathological findings associated with microscopic "small vessel disease" (SVD) in the aetiology of VP. The severity of microscopic SVD pathology (perivascular pallor, gliosis, hyaline thickening, and enlargement of perivascular spaces) and the presence of macroscopically visible infarcts were assessed in 17 patients with parkinsonism and no pathological evidence of either Parkinson's disease or any histopathological condition known to be associated with a parkinsonian syndrome, and compared with age-matched controls. Microscopic SVD pathology was significantly more severe in the parkinsonian brains. Most patients presented with bilateral bradykinesia and rigidity together with a gait disorder characterised predominantly by a shuffling gait. Four patients presented acutely with hemiparesis and then progressed to develop a parkinsonian syndrome. They could be distinguished from the remaining VP patients by the presence at autopsy of macroscopically visible lacunar infarcts in regions where contralateral thalamocortical drive might be reduced. The clinical features at presentation varied according to the speed of onset and the underlying vascular pathological state. New clinical criteria for a diagnosis of VP are proposed based on the clinicopathological findings of this study. Copyright 2004 Movement Disorder Society