Magnetic resonance imaging predictors of cognition in mild cognitive impairment.
OBJECTIVE
To describe magnetic resonance imaging characteristics in a large sample of subjects with mild cognitive impairment (MCI) and to investigate associations between these characteristics and cognition.


METHODS
Cohort study.


METHODS
Baseline data of a randomized, double-blind, placebo-controlled clinical trial of galantamine in MCI.


METHODS
Included in the study were 896 subjects with MCI (age [mean +/- SD], 70 +/- 9 years; 54% women) with available clinical and magnetic resonance imaging data.


METHODS
Neuropsychology: Alzheimer Disease Assessment Scale, cognitive subscale, MCI version, assessing global cognition; delayed recall on the New York University Paragraph Recall Test, assessing episodic memory; and Digit Symbol Substitution Test, assessing executive function. Neuroimaging: Medial Temporal Lobe Atrophy (MTA) Rating Scale (0-4) and Age-Related White Matter Changes Scale (0-30), assessing white matter hyperintensities (WMHs); and lacune counts.


RESULTS
Median MTA score was 2 (range, 0-4), and mean (+/- SD) Age-Related White Matter Changes Scale score 6.0 (+/- 4.7). Lacunes were present in 33% of subjects. In unadjusted models, increasing MTA and WMHs were associated with poorer performance on all cognitive tests, and lacunes with poorer performance on the Alzheimer Disease Assessment Scale, cognitive subscale, MCI version, and the Digit Symbol Substitution Test. In multivariable models, including magnetic resonance imaging measures simultaneously, MTA remained a predictor of cognition, whereas WMH had no independent predictive value. There was an interaction between MTA and lacunes: the strength of the association with the Digit Symbol Substitution Test increased with decreasing MTA.


CONCLUSIONS
Medial temporal lobe atrophy seems to be a more important predictor of cognition than small-vessel disease in MCI. Lacunes were associated with performance on the Digit Symbol Substitution Test, especially in subjects with milder MTA. Although WMHs were prevalent and associated with cognition in unadjusted analyses, there was no discernible association between WMHs and the cognitive measures in this study after adjustment for age.
van de Pol
Laura A
LA
Department of Neurology, Alzheimer Centre, VU Medical Centre, Vrije Universiteit Amsterdam, De Boelelaan 1117, PO Box 7057, 1007 MB Amsterdam, the Netherlands. L.vandepol@vumc.nl
Korf
Esther S C
ES
van der Flier
Wiesje M
WM
Brashear
H Robert
HR
Fox
Nick C
NC
Barkhof
Frederik
F
Scheltens
Philip
P
D000368:Aged; D000544:Alzheimer Disease / Q000473:pathology / Q000503:physiopathology; D001284:Atrophy / Q000209:etiology / Q000473:pathology* / Q000503:physiopathology; D020520:Brain Infarction / Q000473:pathology / Q000503:physiopathology; D003072:Cognition Disorders / Q000209:etiology / Q000473:pathology* / Q000503:physiopathology; D015140:Dementia, Vascular / Q000473:pathology / Q000503:physiopathology; D018450:Disease Progression; D004311:Double-Blind Method; D005260:Female; D006624:Hippocampus / Q000098:blood supply / Q000473:pathology* / Q000503:physiopathology; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000379:methods* / Q000592:standards; D008297:Male; D008569:Memory Disorders / Q000209:etiology / Q000473:pathology* / Q000503:physiopathology; D008875:Middle Aged; D009413:Nerve Fibers, Myelinated / Q000473:pathology; D010919:Placebos; D011237:Predictive Value of Tests; D011379:Prognosis
D010919:Placebos