title: The Unified Parkinson's Disease Rating Scale as a predictor of peak aerobic capacity and ambulatory function.
abstract: The Unified Parkinson's Disease Rating Scale (UPDRS) is a widely applied index of disease severity. Our objective was to assess the utility of UPDRS for predicting peak aerobic capacity (VO2 peak) and ambulatory function. Participants (n = 70) underwent evaluation for UPDRS (Total and Motor ratings), VO2 peak, 6-minute walk distance (6MW), and 30-foot self-selected walking speed (SSWS). Using regression, we determined the extent to which the Total and Motor UPDRS scores predicted each functional capacity measure after adjusting for age and sex. We also tested whether adding the Hoehn and Yahr scale (H-Y) to the model changed predictive power of the UPDRS. Adjusted for age and sex, both the Total UPDRS and Motor UPDRS subscale failed to predict VO2 peak. The Total UPDRS did weakly predict 6MW and SSWS (both p < 0.05), but the Motor UPDRS subscale did not predict these ambulatory function tests. After adding H-Y to the model, Total UPDRS was no longer an independent predictor of 6MW but remained a predictor of SSWS. We conclude that Total and Motor UPDRS rating scales do not predict VO2 peak, but that a weak relationship exists between Total UPDRS and measures of ambulatory function.
authors: Department of Neurology, University of Maryland School of Medicine, Baltimore VA Medical Center Geriatrics Service/GRECC, BT(18) GR, 10 North Greene St, Baltimore, MD 21201-1524, USA. fivey@grecc.umaryland.edu
authors: Frederick M
authors: FM
authors: Ivey
authors: Leslie I
authors: LI
authors: Katzel
authors: John D
authors: JD
authors: Sorkin
authors: Richard F
authors: RF
authors: Macko
authors: Lisa M
authors: LM
authors: Shulman
mesh_terms: D003430:Cross-Sectional Studies; D004185:Disability Evaluation; D017079:Exercise Tolerance / Q000502:physiology*; D005260:Female; D006801:Humans; D008297:Male; D009460:Neurologic Examination; D010300:Parkinson Disease / Q000175:diagnosis* / Q000503:physiopathology*; D011237:Predictive Value of Tests; D017064:Process Assessment, Health Care; D012044:Regression Analysis; D012720:Severity of Illness Index; D016138:Walking / Q000502:physiology*