title: Apathy, but not depression, reflects inefficient cognitive strategies in Parkinson's disease.
abstract: BACKGROUND
  The relationship between apathy, depression and cognitive impairment in Parkinson's disease (PD) is still controversial. The objective of this study is to investigate whether apathy and depression are associated with inefficient cognitive strategies in PD.
  
  
  METHODS
  In this prospective clinical cohort study conducted in a university-based clinical and research movement disorders center we studied 48 PD patients. Based on clinical evaluation, they were classified in two groups: PD with apathy (PD-A group, n = 23) and PD without apathy (PD-NA group, n = 25). Patients received clinical and neuropsychological evaluations. The clinical evaluation included: Apathy Evaluation Scale-patient version, Hamilton Depression Rating Scale-17 items, the Unified Parkinson's Disease Rating Scale and the Hoehn and Yahr staging system; the neuropsychological evaluation explored speed information processing, attention, working memory, executive function, learning abilities and memory, which included several measures of recall (immediate free, short delay free, long delay free and cued, and total recall).
  
  
  RESULTS
  PD-A and PD-NA groups did not differ in age, disease duration, treatment, and motor condition, but differed in recall (p<0.001) and executive tasks (p<0.001). Immediate free recall had the highest predictive value for apathy (F = 10.94; p = 0.002). Depression and apathy had a weak correlation (Pearson index= 0.3; p<0.07), with three items of the depression scale correlating with apathy (Pearson index between .3 and.4; p<0.04). The depressed and non-depressed PD patients within the non-apathetic group did not differ.
  
  
  CONCLUSIONS
  Apathy, but not depression, is associated with deficit in implementing efficient cognitive strategies. As the implementation of efficient strategies relies on the fronto-striatal circuit, we conclude that apathy, unlike depression, is an early expression of executive impairment in PD.
authors: Division of Movement Disorders, Department of Neurology, New York University School of Medicine, New York, New York, United States of America. sara78_96@yahoo.it
authors: Sara
authors: S
authors: Varanese
authors: Bernardo
authors: B
authors: Perfetti
authors: Maria Felice
authors: MF
authors: Ghilardi
authors: Alessandro
authors: A
authors: Di Rocco
mesh_terms: D000368:Aged; D057565:Apathy / Q000502:physiology*; D003071:Cognition / Q000502:physiology*; D003710:Demography; D003863:Depression / Q000150:complications* / Q000503:physiopathology*; D005260:Female; D006801:Humans; D008297:Male; D009483:Neuropsychological Tests; D010300:Parkinson Disease / Q000150:complications / Q000503:physiopathology* / Q000523:psychology*; D012044:Regression Analysis