Levodopa-induced dyskinesia in Atypical Parkinsonism: A population-based cohort study (P3.8-011)

Objective: Investigate levodopa-induced dyskinesia in a population-based cohort of atypical parkinsonism. Background: Few studies have examined levodopa-induced dyskinesia in atypical parkinsonism. Design/Methods: In our 1991–2010 population-based parkinsonism-incident cohort of Olmsted County, MN, we identified all patients with atypical parkinsonisms and abstracted information about levodopa-induced dyskinesia. We subsequently compared atypical parkinsonism patients to Parkinson disease (PD) patients from the same population-based cohort. Results: Data about levodopa use and dyskinesia was available for 337/344 atypical parkinsonism patients (98.0%). Among these, 150 (44.5%) were treated with levodopa; 11.3% of levodopa-treated patients developed dyskinesia. Among dyskinetic patients, median age at diagnosis was 73.5 years (range: 54–80), 58.8% were male, the median follow-up time from levodopa initiation to dyskinesia onset was 3 years (range: 2–5), and the median levodopa dose was 600 mg (range: 300–900). Dyskinesia severity led to levodopa adjustments or amantadine initiation in eight patients, with improvement in seven. Patients with dyskinesia were diagnosed with parkinsonism at a significantly younger age compared to patients without dyskinesia (p=0.03) with no other differences between groups. In models adjusted for age, sex, and levodopa dose, patients with atypical parkinsonism have lower odds of developing dyskinesia compared to PD patients (OR=0.31, 95% CI 0.17, 0.57; p Conclusions: Levodopa-induced dyskinesia affected only 11.3% of patients with atypical parkinsonism. Atypical parkinsonisms are associated with lower odds of developing levodopa-induced dyskinesia compared to PD, independent of levodopa dose. Disclosure: Dr. Turcano has nothing to disclose. Dr. Stang has nothing to disclose. Dr. Bower has nothing to disclose. Dr. Wennberg has nothing to disclose. Dr. Ahlskog has nothing to disclose. Dr. Mielke has received personal compensation for consulting, serving on a scientific advisory board, speaking, or other activities with Eli Lilly and Lysosomal Therapeutics, Inc. Dr. Mielke has received research support from Biogen, Roche, and Lundbeck. Dr. Savica has nothing to disclose.