title: Predictors of dementia in Parkinson disease: a prospective cohort study.
abstract: OBJECTIVE
  We investigated an array of possible markers of early dementia in Parkinson disease.
  
  
  METHODS
  We performed a comprehensive assessment of autonomic, sleep, psychiatric, visual, olfactory, and motor manifestations in 80 patients with Parkinson disease who were dementia-free at baseline. After 4.4 years' follow-up, patients were evaluated for dementia. Predictive variables were assessed using logistic regression adjusting for disease duration, follow-up duration, age, and sex.
  
  
  RESULTS
  Of 80 patients, 27 (34%) developed dementia. Patients destined to develop dementia were older and more often male (odds ratio [OR] = 3.64, p = 0.023). Those with baseline mild cognitive impairment had increased dementia risk (OR = 22.5, p < 0.001). REM sleep behavior disorder at baseline dramatically increased dementia risk (OR = 49.7, p = 0.001); however, neither daytime sleepiness nor insomnia predicted dementia. Higher baseline blood pressure increased dementia risk (OR = 1.37 per 10 mm Hg, p = 0.032). Orthostatic blood pressure drop was strongly associated with dementia risk (OR = 1.84 per 10 mm Hg, p < 0.001); having a systolic drop of >10 mm Hg increased dementia odds 7-fold (OR = 7.3, p = 0.002). Abnormal color vision increased dementia risk (OR = 3.3, p = 0.014), but olfactory dysfunction did not. Among baseline motor variables, proportion of gait involvement (OR = 1.12, p = 0.023), falls (OR = 3.02, p = 0.042), and freezing (OR = 2.63, p = 0.013), as well as the Purdue Pegboard Test (OR = 0.67, p = 0.049) and alternate tap test (OR = 0.97, p = 0.033) predicted dementia.
  
  
  CONCLUSIONS
  Cardiovascular autonomic dysfunction, REM sleep behavior disorder, color discrimination ability, and gait dysfunction strongly predict development of dementia in Parkinson disease.
authors.affiliation: From the Department of Neurology and Neurosurgery (J.B.M.A., S.R.R., R.B.P.), McGill University, Montreal; Centre d'Études Avancées en Médecine du Sommeill (J.-F.G., J.-A.B., V.L., M.P., J.M., R.B.P.), Hôpital du Sacré-coeur de Montréal; Department of Psychology (J.-F.G., J.-A.B.), Université du Québec à Montréal; and Department of Psychiatry (J.M.), Université de Montreal, Canada.
authors.forename: Julius B M
authors.initials: JB
authors.lastname: Anang
authors.affiliation: From the Department of Neurology and Neurosurgery (J.B.M.A., S.R.R., R.B.P.), McGill University, Montreal; Centre d'Études Avancées en Médecine du Sommeill (J.-F.G., J.-A.B., V.L., M.P., J.M., R.B.P.), Hôpital du Sacré-coeur de Montréal; Department of Psychology (J.-F.G., J.-A.B.), Université du Québec à Montréal; and Department of Psychiatry (J.M.), Université de Montreal, Canada. ron.postuma@mcgill.ca gagnon.jean-francois.2@uqam.ca.
authors.forename: Jean-Francois
authors.initials: JF
authors.lastname: Gagnon
authors.affiliation: From the Department of Neurology and Neurosurgery (J.B.M.A., S.R.R., R.B.P.), McGill University, Montreal; Centre d'Études Avancées en Médecine du Sommeill (J.-F.G., J.-A.B., V.L., M.P., J.M., R.B.P.), Hôpital du Sacré-coeur de Montréal; Department of Psychology (J.-F.G., J.-A.B.), Université du Québec à Montréal; and Department of Psychiatry (J.M.), Université de Montreal, Canada.
authors.forename: Josie-Anne
authors.initials: JA
authors.lastname: Bertrand
authors.affiliation: From the Department of Neurology and Neurosurgery (J.B.M.A., S.R.R., R.B.P.), McGill University, Montreal; Centre d'Études Avancées en Médecine du Sommeill (J.-F.G., J.-A.B., V.L., M.P., J.M., R.B.P.), Hôpital du Sacré-coeur de Montréal; Department of Psychology (J.-F.G., J.-A.B.), Université du Québec à Montréal; and Department of Psychiatry (J.M.), Université de Montreal, Canada.
authors.forename: Silvia Rios
authors.initials: SR
authors.lastname: Romenets
authors.affiliation: From the Department of Neurology and Neurosurgery (J.B.M.A., S.R.R., R.B.P.), McGill University, Montreal; Centre d'Études Avancées en Médecine du Sommeill (J.-F.G., J.-A.B., V.L., M.P., J.M., R.B.P.), Hôpital du Sacré-coeur de Montréal; Department of Psychology (J.-F.G., J.-A.B.), Université du Québec à Montréal; and Department of Psychiatry (J.M.), Université de Montreal, Canada.
authors.forename: Veronique
authors.initials: V
authors.lastname: Latreille
authors.affiliation: From the Department of Neurology and Neurosurgery (J.B.M.A., S.R.R., R.B.P.), McGill University, Montreal; Centre d'Études Avancées en Médecine du Sommeill (J.-F.G., J.-A.B., V.L., M.P., J.M., R.B.P.), Hôpital du Sacré-coeur de Montréal; Department of Psychology (J.-F.G., J.-A.B.), Université du Québec à Montréal; and Department of Psychiatry (J.M.), Université de Montreal, Canada.
authors.forename: Michel
authors.initials: M
authors.lastname: Panisset
authors.affiliation: From the Department of Neurology and Neurosurgery (J.B.M.A., S.R.R., R.B.P.), McGill University, Montreal; Centre d'Études Avancées en Médecine du Sommeill (J.-F.G., J.-A.B., V.L., M.P., J.M., R.B.P.), Hôpital du Sacré-coeur de Montréal; Department of Psychology (J.-F.G., J.-A.B.), Université du Québec à Montréal; and Department of Psychiatry (J.M.), Université de Montreal, Canada.
authors.forename: Jacques
authors.initials: J
authors.lastname: Montplaisir
authors.affiliation: From the Department of Neurology and Neurosurgery (J.B.M.A., S.R.R., R.B.P.), McGill University, Montreal; Centre d'Études Avancées en Médecine du Sommeill (J.-F.G., J.-A.B., V.L., M.P., J.M., R.B.P.), Hôpital du Sacré-coeur de Montréal; Department of Psychology (J.-F.G., J.-A.B.), Université du Québec à Montréal; and Department of Psychiatry (J.M.), Université de Montreal, Canada. ron.postuma@mcgill.ca gagnon.jean-francois.2@uqam.ca.
authors.forename: Ronald B
authors.initials: RB
authors.lastname: Postuma
mesh_terms: D000367:Age Factors; D000368:Aged; D001794:Blood Pressure; D060825:Cognitive Dysfunction / Q000453:epidemiology / Q000209:etiology; D003117:Color Vision Defects / Q000453:epidemiology; D003704:Dementia / Q000453:epidemiology* / Q000209:etiology*; D005260:Female; D005500:Follow-Up Studies; D005684:Gait; D006801:Humans; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D010300:Parkinson Disease / Q000150:complications* / Q000453:epidemiology*; D011446:Prospective Studies; D020187:REM Sleep Behavior Disorder / Q000453:epidemiology; D012307:Risk Factors; D012737:Sex Factors; D013997:Time Factors