title: Cognitive function in the early phase of Parkinson's disease, a five-year follow-up.
abstract: BACKGROUND
  Presence of mild cognitive impairment (MCI) as a predictor for Parkinson's disease dementia (PDD) has been discussed from a clinical perspective. Recently, a Movement Disorder Society (MDS) commissioned Task Force published guidelines for PD-MCI. However, long-term follow-ups of the PD-MCI guidelines for the prediction of PDD have been sparse.
  
  
  METHODS
  In a community-based cohort of PD, the MDS guidelines for PD-MCI and consensus criteria for PDD were applied on 147 subjects. The predictive ability of PD-MCI for PDD was investigated. Additionally, baseline comparisons were conducted between MCI that converted to PDD and those who did not, and evolvement of motor function was investigated.
  
  
  RESULTS
  One fourth of the population developed PDD. MCI and age at baseline predicted later occurrence of PDD, and baseline results of tests measuring episodic memory, visuospatial function, semantic fluency, and mental flexibility differed between MCI converters and non-converters. Postural instability/gait (PIGD) phenotype and education did not predict later occurrence of PDD, but increased postural/gait disturbances were shown across time in those developing dementia.
  
  
  CONCLUSIONS
  The new PD-MCI guidelines are useful to detect patients at risk for developing PDD. The PIGD phenotype at diagnosis was not a predictor of PDD within 5 years, but the study supports a temporal association between postural/gait disturbances and PDD. Older patients with PD-MCI at baseline with decline in episodic memory, semantic fluency, and mental flexibility need to be carefully monitored regarding cognition and likely also for fall risk.
authors: Department of Pharmacology and Clinical Neuroscience, Umeå University, Umeå, Sweden.
authors: M E
authors: ME
authors: Domellöf
authors: Department of Pharmacology and Clinical Neuroscience, Umeå University, Umeå, Sweden.|Department of Integrative Medical Biology, Umeå University, Umeå, Sweden.|Umeå center of functional Brain Imaging, Umeå University, Umeå, Sweden.
authors: U
authors: U
authors: Ekman
authors: Department of Pharmacology and Clinical Neuroscience, Umeå University, Umeå, Sweden.
authors: L
authors: L
authors: Forsgren
authors: Department of Community Medicine and Rehabilitation, Geriatric Medicine, Umeå University, Umeå, Sweden.
authors: E
authors: E
authors: Elgh
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D003071:Cognition; D060825:Cognitive Dysfunction / Q000175:diagnosis* / Q000209:etiology*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008875:Middle Aged; D009483:Neuropsychological Tests; D010300:Parkinson Disease / Q000150:complications* / Q000523:psychology*
keywords: Parkinson's Disease; cohort study; dementia; mild cognitive impairment; motor dysfunction