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

Objective To 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. Methods We 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. Results Levodopa 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). Conclusions The dyskinesia risk for levodopa-treated patients with DLB or PDD was substantially less than for levodopa-treated patients with PD.