title: Cognitive decline in early Parkinson's disease.
abstract: Data on the prevalence and severity of cognitive impairment among patients with newly diagnosed idiopathic Parkinson's disease (PD) is limited. Using a prospectively collected clinical database, we studied the longitudinal trend of mini-mental state examination (MMSE) change and baseline factors predictive for MMSE decline. One hundred six patients with mean age of 61.2 years and mean baseline MMSE of 27.8 +/- 2.3 were studied. MMSE increased by 0.4 points/year among patients without cognitive decline (n = 73) and decreased by 2.39 points/year among patients with cognitive decline (n = 33). Univariate analysis demonstrated education, age of diagnosis, depression, and diabetes mellitus to be associated with cognitive decline. Motor scores and hallucination were not associated with cognitive decline. Multivariate analysis demonstrated higher level of education to be protective (HR = 0.91, 95% CI 0.82-0.99, P = 0.047) and depression having borderline significance in predicting cognitive decline (HR = 2.00, 95% CI 0.97-4.15, P = 0.061). We found that 31% of newly diagnosed idiopathic PD patients have measurable cognitive decline at an early stage of disease. Higher education is protective while depression may be predictive of cognitive decline.
authors.affiliation: Department of Neurology, National Neuroscience Institute, 11 Jalan Tan Tock Seng, Singapore 308433, Singapore. nagaendran_kandiah@nni.com.sg
authors.forename: Nagaendran
authors.initials: N
authors.lastname: Kandiah
authors.forename: Kaavya
authors.initials: K
authors.lastname: Narasimhalu
authors.forename: Puay-Ngoh
authors.initials: PN
authors.lastname: Lau
authors.forename: Soo-Hoon
authors.initials: SH
authors.lastname: Seah
authors.forename: Wing Lok
authors.initials: WL
authors.lastname: Au
authors.forename: Louis C S
authors.initials: LC
authors.lastname: Tan
mesh_terms: D000368:Aged; D000704:Analysis of Variance; D003072:Cognition Disorders / Q000209:etiology*; D004522:Educational Status; D005260:Female; D006801:Humans; D053208:Kaplan-Meier Estimate; D016014:Linear Models; D008137:Longitudinal Studies; D008297:Male; D008609:Mental Status Schedule; D008875:Middle Aged; D009483:Neuropsychological Tests; D010300:Parkinson Disease / Q000150:complications* / Q000401:mortality