title: Plasma insulin-like growth factor 1 is associated with cognitive impairment in Parkinson's disease.
abstract: OBJECTIVE
  The aim of this study was to test plasma insulin-like growth factor 1 (IGF-1) change in Parkinson's disease (PD) and essential tremor (ET), and assess the association of plasma IGF-1 level with motor and nonmotor symptoms in PD and ET.
  
  
  METHODS
  Plasma IGF-1 was measured in 100 PD patients, 40 ET patients, and 76 healthy controls. Motor and nonmotor symptoms were assessed by different scales. Spearman correlation test and linear logistic model were used to analyze the correlation of plasma IGF-1 with motor and nonmotor symptoms of PD and ET.
  
  
  RESULTS
  The plasma IGF-1 level was significantly increased in PD compared to healthy controls and ET patients. In addition, low plasma IGF-1 was correlated with low Mini-Mental State Examination (MMSE) scores in PD patients. However, no correlation was found between plasma IGF-1 and MMSE scores in ET patients.
  
  
  CONCLUSIONS
  Plasma IGF-1 increased significantly in PD but remained unchanged in ET. A low plasma IGF-1 level was associated with poor cognitive performance in PD but not in ET patients.
authors: Department of Neurology and Institute of Neurology, Ruijin Hospital afﬁliated to Shanghai Jiao Tong University School of Medicine, Shanghai, PR China.
authors: Jianfang
authors: J
authors: Ma
authors: Qianwen
authors: Q
authors: Jiang
authors: Jing
authors: J
authors: Xu
authors: Qian
authors: Q
authors: Sun
authors: Yuan
authors: Y
authors: Qiao
authors: Wei
authors: W
authors: Chen
authors: Yiwen
authors: Y
authors: Wu
authors: Ying
authors: Y
authors: Wang
authors: Qin
authors: Q
authors: Xiao
authors: Jun
authors: J
authors: Liu
authors: Huidong
authors: H
authors: Tang
authors: Shengdi
authors: S
authors: Chen
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D060825:Cognitive Dysfunction / Q000097:blood / Q000209:etiology*; D020329:Essential Tremor / Q000097:blood* / Q000523:psychology; D005260:Female; D006801:Humans; D007334:Insulin-Like Growth Factor I / Q000378:metabolism*; D008297:Male; D008875:Middle Aged; D009483:Neuropsychological Tests; D010300:Parkinson Disease / Q000097:blood* / Q000523:psychology
chemical_list: D007334:Insulin-Like Growth Factor I