The association between cognitive impairment and physical disability in multiple sclerosis.
BACKGROUND
The association between cognitive impairment and physical disability was examined in a larger, more representative sample of patients with multiple sclerosis (MS) than in previous studies.


METHODS
Two hundred and fifty-three patients attending an MS clinic were assessed with respect to physical disability using the Expanded Disability Status Scale and cognitive impairment using a battery of neuropsychological tests.


RESULTS
Physical disability correlated with duration of disease; cognitive impairment did not. Virtually all measures derived from the cognitive battery were significantly correlated with physical disability. Three measures of speeded information processing and one involving delayed recall of verbal material were unique predictors of disability status. The relationship between cognitive impairment and physical disability was equivalent for patients with shorter (< 3 years) versus longer (> 10 years) disease duration. Cognitive impairment correlated with the rate of disability progression as reflected by the progression index.


CONCLUSIONS
Cognitive impairment is more closely associated with physical disability than most previous studies indicate. This relationship appears to be stable throughout the duration of MS, although this conclusion is qualified by the cross-sectional design of the study. Further attention should be paid to cognitive impairment as a possible predictor of the rate of patients' physical decline.
Lynch
Sharon G
SG
Department of Neurology, University of Kansas Medical Center, Kansas City, KS 66160, USA.
Parmenter
Brett A
BA
Denney
Douglas R
DR
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D003071:Cognition; D003072:Cognition Disorders / Q000209:etiology*; D006233:Persons with Disabilities; D005260:Female; D006801:Humans; D008297:Male; D017533:Marital Status; D008875:Middle Aged; D009043:Motor Activity; D009103:Multiple Sclerosis / Q000503:physiopathology* / Q000523:psychology*; D009483:Neuropsychological Tests