R Erro1, M Picillo1, M Amboni1,2, R Savastano3, S Scannapieco1, S Cuoco1, G Santangelo4, C Vitale2,5, M T Pellecchia1, P Barone1. 1. Center for Neurodegenerative Disease - CEMAND, Department of Medicine, Surgery and Dentistry 'Scuola Medica Salernitana', University of Salerno, Baronissi (SA), Italy. 2. Institute of Diagnosis and Health, IDC-Hermitage Capodimonte, Naples, Italy. 3. Azienda Ospedaliera Universitaria 'San Giovanni di Dio e Ruggi d'Aragona', Salerno, Italy. 4. Department of Psychology, University of Campania Luigi Vanvitelli, Caserta, Italy. 5. Department of Motor Sciences and Wellness, University 'Parthenope', Naples, Italy.
Abstract
BACKGROUND AND PURPOSE: Parkinson disease (PD) patients are classically classified according to two alternative motor subtyping methods: (i) tremor-dominant versus postural instability and gait disorder; (ii) tremor-dominant versus akinetic-rigid. The degree of overlap between the two classification systems at diagnosis of PD and their temporal stability, as well as the correspondence between the two systems, were examined over a follow-up period of 4 years. METHODS: Newly diagnosed, untreated PD patients were classified as tremor-dominant versus postural instability and gait disorder and tremor-dominant versus akinetic-rigid at baseline and after 2 and 4 years. RESULTS: There was a poor overlap between the two classification systems at any time point and baseline subtype status could not predict 4-year subtype membership. In fact, about half of our cohort shifted category during the first 2 years, regardless of the classification scheme adopted. A lower rate of shift was observed from 2- to 4-year follow-up. CONCLUSIONS: The two classical motor subtyping methods of PD poorly overlap, which implies that a patient can be categorized as tremor-dominant in one classification system but not in the other. Moreover, their temporal instability undermines their prognostic value in the early stage of PD.
BACKGROUND AND PURPOSE:Parkinson disease (PD) patients are classically classified according to two alternative motor subtyping methods: (i) tremor-dominant versus postural instability and gait disorder; (ii) tremor-dominant versus akinetic-rigid. The degree of overlap between the two classification systems at diagnosis of PD and their temporal stability, as well as the correspondence between the two systems, were examined over a follow-up period of 4 years. METHODS: Newly diagnosed, untreated PDpatients were classified as tremor-dominant versus postural instability and gait disorder and tremor-dominant versus akinetic-rigid at baseline and after 2 and 4 years. RESULTS: There was a poor overlap between the two classification systems at any time point and baseline subtype status could not predict 4-year subtype membership. In fact, about half of our cohort shifted category during the first 2 years, regardless of the classification scheme adopted. A lower rate of shift was observed from 2- to 4-year follow-up. CONCLUSIONS: The two classical motor subtyping methods of PD poorly overlap, which implies that a patient can be categorized as tremor-dominant in one classification system but not in the other. Moreover, their temporal instability undermines their prognostic value in the early stage of PD.
Authors: Robert S Eisinger; Daniel Martinez-Ramirez; Adolfo Ramirez-Zamora; Christopher W Hess; Leonardo Almeida; Michael S Okun; Aysegul Gunduz Journal: Parkinsonism Relat Disord Date: 2019-05-19 Impact factor: 4.891