Motor features in Parkinson's disease with normal olfactory function

BackgroundNormosmic Parkinson's disease (PD) might be a unique clinical phenotype with a more benign course when compared with hyposmic PD. ObjectiveThe objective of this study was to evaluate motor features and the acute levodopa response according to olfactory function. MethodsA total of 169 de novo PD patients that underwent olfactory testing and acute levodopa challenge for clinical prediction of sustained long-term dopaminergic response were evaluated. ResultsThe overall frequency of normosmia was 33%. Normosmic PD patients scored nonsignificantly different to hyposmic/anosmic patients on motor scale and on degree of improvement with levodopa. Motor scores at follow-up were comparable among groups. ConclusionsNormal olfactory function is common in early PD and was not associated with a different motor phenotype when compared with PD patients with olfactory dysfunction. (c) 2016 International Parkinson and Movement Disorder Society