title: Prevalence and relation of dementia to various factors in Parkinson's disease.
abstract: OBJECTIVE
  Parkinson's disease is a chronic neurodegenerative disorder characterized by bradykinesia, rigidity, and resting tremor. Dementia, among its non-motor symptoms, is a debilitating complication affecting intellectual functioning. The aim of the present study was to determine the prevalence of dementia in Parkinson's disease and its relation to age, gender and stage of the disease.
  
  
  METHODS
  A retrospective chart analysis was performed on Parkinson's disease patients seen in a community-based Parkinson's disease and movement disorder clinic between 2005 and 2010.
  
  
  RESULTS
  A total of 310 patients were included in this survey, among whom 61 patients (19.7%) with Parkinson's disease met the criteria for dementia. Age was found to be a significant factor in developing dementia, with 90% of patients with dementia aged ≥70. Gender, however, was not correlated with dementia in Parkinson's disease. On analysis of stage at which dementia developed, progression of the disease was positively correlated with prevalence of dementia.
  
  
  CONCLUSIONS
  As age increases, the chances of developing dementia increase. Dementia, contrarily, is not selective between genders. The likelihood of developing dementia increases as the stage of disease advances. Further research is required in order to understand underlying mechanisms of dementia in Parkinson's disease.
authors.affiliation: Parkinson's Clinic of Eastern Toronto and Movement Disorders Center, Toronto, Canada. ranaaq@yahoo.com
authors.forename: Abdul Qayyum
authors.initials: AQ
authors.lastname: Rana
authors.forename: Muhammad Saad
authors.initials: MS
authors.lastname: Yousuf
authors.forename: Sughra
authors.initials: S
authors.lastname: Naz
authors.forename: Nour
authors.initials: N
authors.lastname: Qa'aty
mesh_terms: D000367:Age Factors; D000368:Aged; D002170:Canada / Q000453:epidemiology; D003704:Dementia / Q000150:complications / Q000453:epidemiology*; D018450:Disease Progression; D005260:Female; D006801:Humans; D008297:Male; D010300:Parkinson Disease / Q000150:complications / Q000175:diagnosis / Q000523:psychology*; D015995:Prevalence; D012189:Retrospective Studies; D012720:Severity of Illness Index; D012737:Sex Factors