title: Cognitive impairment is common in Parkinson's disease without dementia in the early and middle stages in a Han Chinese cohort.
abstract: BACKGROUND
  Cognitive impairments have been reported to be common in Parkinson's disease (PD) without dementia, which occur not only in the late stages of PD, but also in the early and middle stages. Until now, no reports on the profile of cognitive impairment in Chinese non-demented PD population have been published yet. Different ethnic groups should be assessed to improve evaluation of cognitive impairment in clinical practice. The aims of this study are to estimate the frequencies and profile of cognitive impairments and to explore the risk factors of cognitive impairments in Han Chinese non-demented PD patients at early and middle stages.
  
  
  METHODS
  Eighty non-demented PD patients in early and middle stages and 86 healthy controls were invited to participate in this study. Neuropsychological batteries testing executive function, visuospatial function, memory and attention were evaluated. Cognitive impairments were defined as impaired performance in at least one cognitive domain.
  
  
  RESULTS
  Neuropsychological batteries detected 30 cases with executive dysfunction, 27 cases with memory impairment, eight cases with visuospatial dysfunction and seven cases with attention impairment. As many as 48 cases (60%) of PD patients presented cognitive impairment. Logistic regression analysis indicated that education level and Hoehn & Yahr stage were associated with cognitive impairment in PD.
  
  
  CONCLUSIONS
  Cognitive impairment is common in the early and middle stages of PD without dementia; executive function is the most common domain impaired in a Chinese PD population. Cognitive impairment might be predicted by lower education level and higher Hoehn and Yahr stage.
authors.affiliation: Department of Neurology, The First Affiliated Hospital, Sun Yat-sen University, Guangzhou, 510080, PR China. wuqi8733@163.com
authors.forename: Qi
authors.initials: Q
authors.lastname: Wu
authors.forename: Ling
authors.initials: L
authors.lastname: Chen
authors.forename: Yifan
authors.initials: Y
authors.lastname: Zheng
authors.forename: Caixia
authors.initials: C
authors.lastname: Zhang
authors.forename: Linhuan
authors.initials: L
authors.lastname: Huang
authors.forename: Wenyuan
authors.initials: W
authors.lastname: Guo
authors.forename: Yingying
authors.initials: Y
authors.lastname: Fang
authors.forename: Hongyan
authors.initials: H
authors.lastname: Zhou
authors.forename: Yanmei
authors.initials: Y
authors.lastname: Liu
authors.forename: Jie
authors.initials: J
authors.lastname: Chen
authors.forename: Hao
authors.initials: H
authors.lastname: Qian
authors.forename: Wenbiao
authors.initials: W
authors.lastname: Xian
authors.forename: Jinsheng
authors.initials: J
authors.lastname: Zeng
authors.forename: Jinru
authors.initials: J
authors.lastname: Li
authors.forename: Zhuolin
authors.initials: Z
authors.lastname: Liu
authors.forename: Zhong
authors.initials: Z
authors.lastname: Pei
mesh_terms: D000368:Aged; D044466:Asian People / Q000208:ethnology* / Q000523:psychology; D003072:Cognition Disorders / Q000175:diagnosis* / Q000208:ethnology* / Q000523:psychology; D015331:Cohort Studies; D003704:Dementia; D042241:Early Diagnosis; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009483:Neuropsychological Tests; D010300:Parkinson Disease / Q000175:diagnosis* / Q000208:ethnology* / Q000523:psychology; D011569:Psychiatric Status Rating Scales