title: Prognostic factors for early mortality in Parkinson's disease.
abstract: BACKGROUND
  There are few large studies that have evaluated prognostic factors for mortality in Parkinson's disease (PD). This large study aimed to identify demographic and clinical features associated with early mortality in PD.
  
  
  METHODS
  PD patients at the National Neuroscience Institute were identified from the Movement Disorders Database from which demographic information and prospectively collected baseline disease characteristics were obtained. All study patients were linked to the Singapore Registry of Birth and Death to obtain information on vital status through December 31, 2012. The prognostic variables analyzed include patient demographics, baseline disease characteristics, and type of PD medication used. Multivariate Cox regression analysis was carried out to identify factors associated with the risk of mortality in PD.
  
  
  RESULTS
  Of the 1786 PD patients identified, 363 (20.3%) had died during the 11-year study period. Median survival time from diagnosis was 15.8 years (range 0.3-31). Factors associated with higher mortality (HR, 95% CI) were older age at diagnosis (1.06, 1.03-1.08), male gender (2.29, 1.57-3.35), Hoehn & Yahr (HY) stage ≥ 2.5 (1.54, 1.07-2.22), UPDRS motor score ≥ 30 (1.63, 1.13-2.35), higher bradykinesia subscores (1.05, 1.01-1.09) and cognitive impairment (2.30, 1.55-3.41).
  
  
  CONCLUSIONS
  In the largest study to date evaluating baseline disease characteristics prognostic of mortality risk in PD, we found that male gender, older age at diagnosis, higher baseline HY stage, higher baseline UPDRS motor scores, higher bradykinesia subscores and baseline cognitive impairment were associated with early mortality in PD.
authors.affiliation: Department of Neurology, National Neuroscience Institute, 11 Jalan Tan Tock Seng, Singapore 308433, Singapore; Parkinson's Disease and Movement Disorders Centre, Department of Neurology, USA National Parkinson Foundation Centre of Excellence, National Neuroscience Institute, Singapore.
authors.forename: Linda P
authors.initials: LP
authors.lastname: Oosterveld
authors.affiliation: Duke-NUS Graduate Medical School, Singapore.
authors.forename: John C
authors.initials: JC
authors.lastname: Allen
authors.affiliation: Department of Neurology, National Neuroscience Institute, 11 Jalan Tan Tock Seng, Singapore 308433, Singapore; Parkinson's Disease and Movement Disorders Centre, Department of Neurology, USA National Parkinson Foundation Centre of Excellence, National Neuroscience Institute, Singapore; Duke-NUS Graduate Medical School, Singapore.
authors.forename: Giselle
authors.initials: G
authors.lastname: Reinoso
authors.affiliation: Department of Neurology, National Neuroscience Institute, 11 Jalan Tan Tock Seng, Singapore 308433, Singapore; Parkinson's Disease and Movement Disorders Centre, Department of Neurology, USA National Parkinson Foundation Centre of Excellence, National Neuroscience Institute, Singapore.
authors.forename: Soo-Hoon
authors.initials: SH
authors.lastname: Seah
authors.affiliation: Department of Neurology, National Neuroscience Institute, 11 Jalan Tan Tock Seng, Singapore 308433, Singapore; Parkinson's Disease and Movement Disorders Centre, Department of Neurology, USA National Parkinson Foundation Centre of Excellence, National Neuroscience Institute, Singapore.
authors.forename: Kay-Yaw
authors.initials: KY
authors.lastname: Tay
authors.affiliation: Department of Neurology, National Neuroscience Institute, 11 Jalan Tan Tock Seng, Singapore 308433, Singapore; Parkinson's Disease and Movement Disorders Centre, Department of Neurology, USA National Parkinson Foundation Centre of Excellence, National Neuroscience Institute, Singapore.
authors.forename: Wing-Lok
authors.initials: WL
authors.lastname: Au
authors.affiliation: Department of Neurology, National Neuroscience Institute, 11 Jalan Tan Tock Seng, Singapore 308433, Singapore; Parkinson's Disease and Movement Disorders Centre, Department of Neurology, USA National Parkinson Foundation Centre of Excellence, National Neuroscience Institute, Singapore. Electronic address: louis_tan@nni.com.sg.
authors.forename: Louis C S
authors.initials: LC
authors.lastname: Tan
mesh_terms: D000367:Age Factors; D000368:Aged; D005260:Female; D006801:Humans; D053208:Kaplan-Meier Estimate; D008137:Longitudinal Studies; D008297:Male; D008875:Middle Aged; D010300:Parkinson Disease / Q000175:diagnosis* / Q000453:epidemiology / Q000401:mortality*; D011379:Prognosis; D012044:Regression Analysis; D012737:Sex Factors
keywords: Mortality; Parkinson's disease; Prognostic factors; Survival