title: Relationship between clinical phenotypes and cognitive impairment in Parkinson's disease (PD).
abstract: Most patients with idiopathic PD (IPD) show variable degrees of cognitive decline. The purpose of this study was to evaluate the relationship between the predominant motor symptom at the time of disease onset and the level of cognitive function in patients with IPD. A total of 159 patients with IPD were enrolled in this study. The patients' initial motor symptoms were classified into three types: tremor-dominant (TD), bradykinesia and rigidity-dominant (BRD), gait and postural instability-dominant (GPD). Disease severity was rated according to the Hoehn-Yahr classification (H&Y stage). Overall cognitive status was evaluated using the Korean versions of the Mini-Mental State Examination (K-MMSE) and the Modified Mini-Mental State (3MS) tests. The GPD group showed the lowest scores of the K-MMSE/3MS, and the patients with TD showed the best performance in the cognitive analysis (p<0.05). The patients who were older at disease onset showed worse cognitive performance than those the patients who were younger at disease onset (p<0.05). There was no difference in cognitive status according to H&Y stages. The accurate classification of initial motor symptoms and the detailed history, including the exact onset age of IPD, may allow us to predict cognitive decline in IPD.
authors.affiliation: Department of Neurology, Chungnam National University Hospital, College of Medicine, 640 Daesadong, Junggu, Daejon 301-721, South Korea.
authors.forename: Joo Young
authors.initials: JY
authors.lastname: Oh
authors.forename: Ye-Sung
authors.initials: YS
authors.lastname: Kim
authors.forename: Byung Hee
authors.initials: BH
authors.lastname: Choi
authors.forename: Eun Hee
authors.initials: EH
authors.lastname: Sohn
authors.forename: Ae Young
authors.initials: AY
authors.lastname: Lee
mesh_terms: D017668:Age of Onset; D000368:Aged; D000704:Analysis of Variance; D003072:Cognition Disorders / Q000150:complications*; D003866:Depressive Disorder / Q000150:complications; D005260:Female; D006801:Humans; D008297:Male; D010300:Parkinson Disease / Q000150:complications* / Q000523:psychology; D010641:Phenotype; D011569:Psychiatric Status Rating Scales