Striatal dopamine transporter in dementia with Lewy bodies and Parkinson disease

ObjectiveTo investigate the relationship between β-amyloid (Aβ) deposition and striatal dopamine depletion, cognitive functions, and neuropsychiatric symptoms in dementia with Lewy bodies (DLB).MethodsWe consecutively recruited 51 patients with DLB who had undergone a neuropsychological test, Neuropsychiatric Inventory assessment, brain MRI, N-(3-[18F]fluoropropyl)-2β-carbon ethoxy-3β-(4-iodophenyl) PET, and 18F-florbetaben PET within 6 months. The patients were divided into Aβ-negative (DLB-Aβ−, n = 20) and Aβ-positive (DLB-Aβ+, n = 31) groups according to the brain amyloid plaque load score. We performed comparative analyses of dopamine transporter (DAT) activity, neuropsychological profile, and neuropsychiatric symptoms between the 2 groups.ResultsCompared to the DLB-Aβ− group, the DLB-Aβ+ group had a younger age at diagnosis (p = 0.017), poorer performance in attention (p = 0.028) and visuospatial (p = 0.006) functions, and higher proportion of anxiety (p = 0.006) and total neuropsychiatric burden (p = 0.013). Those in the DLB-Aβ+ group also had lower DAT activity in the anterior putamen (p = 0.015) and ventral striatum (p = 0.006) regardless of age, sex, and years of education. In addition, lower DAT activity in the ventral striatum was significantly associated with anxiety and total neuropsychiatric burden in DLB.ConclusionsThis study demonstrated that Aβ deposition in DLB is associated with diagnosis at a younger age, higher cognitive and neuropsychiatric burden, and decreased DAT activity, suggesting that evaluation of clinical features and DAT activity can predict the presence of Aβ in DLB.

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Levodopa-induced dyskinesia in dementia with Lewy bodies and Parkinson disease with dementia

Neurology Clinical Practice ◽

10.1212/cpj.0000000000000703 ◽

2019 ◽

Vol 10 (2) ◽

pp. 156-161

Author(s):

Pierpaolo Turcano ◽

Cole D. Stang ◽

James H. Bower ◽

J. Eric Ahlskog ◽

Bradley F. Boeve ◽

...

Keyword(s):

Parkinson Disease ◽

Dementia With Lewy Bodies ◽

Lewy Bodies ◽

Population Based ◽

Olmsted County ◽

Levodopa Dosage ◽

Younger Age ◽

Increased Risk ◽

Incident Cohort ◽

Median Interval

ObjectiveTo investigate the frequency of levodopa-induced dyskinesia in dementia with Lewy bodies (DLBs) and Parkinson disease with dementia (PDD) and compare these frequencies with patients with incident Parkinson disease (PD) through a population-based cohort study.MethodsWe identified all patients with DLB, PDD, and PD without dementia in a 1991–2010 population-based parkinsonism-incident cohort, in Olmsted County, Minnesota. We abstracted information about levodopa-induced dyskinesia. We compared patients with DLB and PDD with dyskinesia with patients with PD from the same cohort.ResultsLevodopa use and dyskinesia data were available for 141/143 (98.6%) patients with a diagnosis of either DLB or PDD; 87 (61.7%), treated with levodopa. Dyskinesia was documented in 12.6% (8 DLB and 3 PDD) of levodopa-treated patients. Among these patients, median parkinsonism diagnosis age was 74 years (range: 64–80 years); 63.6%, male. The median interval from levodopa initiation to dyskinesia onset was 2 years (range: 3 months–4 years); the median daily levodopa dosage was 600 mg (range: 50–1,600 mg). Dyskinesia severity led to levodopa adjustments in 5 patients, and all improved. Patients with dyskinesia were diagnosed with parkinsonism at a significantly younger age compared with patients without dyskinesia (p < 0.001). Levodopa dosage was unrelated to increased risk of dyskinesias among DLB and PDD. In contrast, 30.1% of levodopa-treated patients with PD developed dyskinesia. In age-, sex-, and levodopa dosage–adjusted models, Patients with DLB and PDD each had lower odds of developing dyskinesia than patients with PD (odds ratio = 0.42, 95% CI 0.21–0.88; p = 0.02).ConclusionsThe dyskinesia risk for levodopa-treated patients with DLB or PDD was substantially less than for levodopa-treated patients with PD.

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