title: Sex Differences in Clinical Features of Early, Treated Parkinson's Disease.
abstract: BACKGROUND
  To improve our understanding of sex differences in the clinical characteristics of Parkinson's Disease, we sought to examine differences in the clinical features and disease severity of men and women with early treated Parkinson's Disease (PD) enrolled in a large-scale clinical trial.
  
  
  METHODS
  Analysis was performed of baseline data from the National Institutes of Health Exploratory Trials in Parkinson's Disease (NET-PD) Long-term Study-1, a randomized, multi-center, double-blind, placebo-controlled study of 10 grams of oral creatine/day in individuals with early, treated PD. We compared mean age at symptom onset, age at PD diagnosis, and age at randomization between men and women using t-test statistics. Sex differences in clinical features were evaluated, including: symptoms at diagnosis (motor) and symptoms at randomization (motor, non-motor, and daily functioning).
  
  
  RESULTS
  1,741 participants were enrolled (62.5% male). No differences were detected in mean age at PD onset, age at PD diagnosis, age at randomization, motor symptoms, or daily functioning between men and women. Differences in non-motor symptoms were observed, with women demonstrating better performance compared to men on SCOPA-COG (Z = 5.064, p<0.0001) and Symbol Digit Modality measures (Z = 5.221, p<0.0001).
  
  
  CONCLUSIONS
  Overall, men and women did not demonstrate differences in clinical motor features early in the course of PD. However, the differences observed in non-motor cognitive symptoms suggests further assessment of the influence of sex on non-motor symptoms in later stages of PD is warranted.
authors.affiliation: Department of Neurology, University of Rochester Medical Center, Rochester, NY, United States of America.
authors.forename: Erika F
authors.initials: EF
authors.lastname: Augustine
authors.affiliation: The University of Texas School of Public Health, Austin, TX, United States of America.
authors.forename: Adriana
authors.initials: A
authors.lastname: Pérez
authors.affiliation: Barrow Neurological Institute, Phoenix, AZ, United States of America.
authors.forename: Rohit
authors.initials: R
authors.lastname: Dhall
authors.affiliation: Department of Neurology, Brigham and Women's Hospital and Harvard Medical School, Boston, MA, United States of America.
authors.forename: Chizoba C
authors.initials: CC
authors.lastname: Umeh
authors.affiliation: Neurological Clinical Research Institute, Massachusetts General Hospital, Boston, MA, United States of America.
authors.forename: Aleksandar
authors.initials: A
authors.lastname: Videnovic
authors.affiliation: Department of Neurology, University of Kentucky, Lexington, KY, United States of America.
authors.forename: Franca
authors.initials: F
authors.lastname: Cambi
authors.affiliation: Department of Neurology, Massachusetts General Hospital and Harvard Medical School, Boston, MA, United States of America.
authors.forename: Anne-Marie A
authors.initials: AM
authors.lastname: Wills
authors.affiliation: Department of Public Health Sciences, Medical University of South Carolina, Charleston, SC, United States of America.
authors.forename: Jordan J
authors.initials: JJ
authors.lastname: Elm
authors.affiliation: Louisiana State University Health Sciences Center, Shreveport, LA, United States of America.
authors.forename: Richard M
authors.initials: RM
authors.lastname: Zweig
authors.affiliation: Department of Neurology, University of Maryland School of Medicine, Baltimore, MD, United States of America.
authors.forename: Lisa M
authors.initials: LM
authors.lastname: Shulman
authors.affiliation: Struthers Parkinson's Center, Minneapolis, MN, United States of America.
authors.forename: Martha A
authors.initials: MA
authors.lastname: Nance
authors.affiliation: University of Colorado Skaggs School of Pharmacy and Pharmaceutical Sciences, Aurora, CO, United States of America.
authors.forename: Jacquelyn
authors.initials: J
authors.lastname: Bainbridge
authors.affiliation: Department of Medicine, University of Alberta‎, Edmonton, AB, Canada; Department of Medical Genetics, University of Alberta‎, Edmonton, AB, Canada; Department of Pediatrics, University of Alberta‎, Edmonton, AB, Canada.
authors.forename: Oksana
authors.initials: O
authors.lastname: Suchowersky
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D003401:Creatine / Q000378:metabolism; D004311:Double-Blind Method; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D010300:Parkinson Disease / Q000378:metabolism / Q000473:pathology*; D012720:Severity of Illness Index; D012727:Sex Characteristics
chemical_list: D003401:Creatine