Baseline motor findings and Parkinson disease prognostic subtypes

Abstract
Objective: To identify the significance of baseline motor features to the lifelong prognostic motor subtypes in a Parkinson disease (PD) cohort. Methods: In a previous study of 166 PD cases, we observed different prognosis in tremor-dominant, akinetic-rigid, and mixed subtypes. This study includes the same cases, but we excluded 10 cases with symptoms of ≥15 years duration at baseline. Relative severity of tremor, bradykinesia/akinesia, and rigidity at baseline were evaluated as predictors of the motor subtypes, which are known to have different prognosis. Results: The most common motor subtype was mixed, followed by akinetic-rigid and then the tremor-dominant. Seventy cases were not receiving antiparkinsonian drugs at baseline. The prognostic subtypes could be predicted at baseline in 85% of all and in 91% of the treatment-naive cases. Sensitivity, specificity, and positive predictive values were strong for the mixed and the akinetic-rigid but weak for the tremor-dominant subtype. Conclusions: Our data show that motor profile at baseline can predict prognosis in most PD cases. These findings can be incorporated into clinical practice.