Postural Instability and Cognitive Dysfunction in Early Parkinson's Disease

• Published in: Canadian journal of neurological sciences 2012-07, Vol.39 (4), p.473-482
• Main Authors: Lee, Jong Moon, Koh, Seong-Beom, Chae, Sung Won, Seo, Woo-Keun, Kwon, Do Young, Kim, Ji Hyun, Oh, Kyungmi, Baik, Jong Sam, Park, Kun Woo
• Format: Article
• Language: English
• Subjects: Aged; Analysis of Variance; Biological and medical sciences; Cognition Disorders - complications; Cognition Disorders - diagnosis; Cognitive ability; Degenerative and inherited degenerative diseases of the nervous system. Leukodystrophies. Prion diseases; Diagnosis, Computer-Assisted; Disability Evaluation; Female; Humans; Learning; Male; Medical sciences; Memory; Mental Status Schedule; Middle Aged; Motor task performance; Movement disorders; Neurodegenerative diseases; Neurology; Neuropsychological Tests; Original Article; Parkinson Disease - complications; Parkinson's disease; Postural Balance - physiology; Posture; Sensation Disorders - complications; Sensation Disorders - diagnosis; Severity of Illness Index; Statistics as Topic; Translation; Vestibular system; Visual perception
• ISSN: 0317-1671; 2057-0155
• DOI: 10.1017/S0317167100013986

Postural instability is one of the most disabling features of Parkinson's disease, usually occurring in late and advanced stages. The aim of this study was to investigate the postural performance of early-stage de novo Parkinson's disease patients with no clinical postural instability using computerized dynamic posturography. We sought to understand the relationship between postural sway and disease severity and the relationship between postural instability quantitatively measured by computerized dynamic posturography and cognitive impairment in early-stage Parkinson's disease patients. Thirty-one subjects with Parkinson's disease and 20 healthy controls were assessed by the computerized dynamic posturography protocol using the sensory organization test and the motor control test. A neuropsychological assessment was also administered. The mean equilibrium score for sensory organization test and the vestibular input ratio were significantly correlated with Hoehn-Yahr stage. No associations between motor latency for any motor control test condition and Hoehn-Yahr stage were found. The equilibrium score for sensory organization test correlated with the mini-mental status examination scores. There was a significant correlation between motor latency for large backward translation and mini-mental status examination scores. There were significant correlations between visual perception/construction/ memory of the neuropsychological battery test and the equilibrium score for sensory organization test and between verbal word learning test, controlled word association test and motor latency for large backward translation. These findings showed the postural instability present in early-stage (Hoehn-Yahr stage 2-2.5) Parkinson's disease. We also found a close relationship between postural instability and cognitive function in Parkinson's disease patients.