White matter changes in healthy elderly persons correlate with attention and speed of mental processing.
OBJECTIVE
To evaluate the association between white matter changes (leukoaraiosis [LA]) seen on magnetic resonance imaging and cognitive functions.


METHODS
Survey of cohorts of neurologically healthy elderly subjects derived consecutively from a population-based random sample.


METHODS
General community, the Helsinki (Finland) Aging Brain Study.


METHODS
Cohorts of neurologically healthy subjects aged 55, 60, 65, 70, 75, 80, and 85 years (n = 20, 18, 19, 18, 17, 17 and 11 subjects, respectively; total N = 120).


METHODS
Leukoaraiosis was rated in the periventricular areas (0 to 24) and the centrum semiovale (0 to 24); also, a total LA score was obtained (0 to 48). The neuropsychological test battery covered memory, verbal intellectual and constructional functions, language, speed and attention, and speed of mental processing, as well as simple psychomotor speed.


RESULTS
Low age-related LA scores and deterioration of cognitive functions were obtained in the normal subjects. When controlling for age, we found that speed and attention, together with the speed of mental processing measured by the Trail Making A and the Stroop tests, correlated with the total LA score. However, there was wide variation between subjects. Comparing groups with and without LA proved the association of LA with Trail Making A time, Stroop test result (words/time and difference/time), and the compound score of speed and attention. Presence of periventricular LA was especially related to speed of mental processing.


CONCLUSIONS
Leukoaraiosis could explain some of the intellectual impairment in the elderly, especially that of slowing of distinct motor and attentional functions, as well as slowing of mental processing. Mild LA in normal aged subjects could also signal brain at risk for further cognitive impairment.
Ylikoski
R
R
Department of Neurology, University of Helsinki, Finland.
Ylikoski
A
A
Erkinjuntti
T
T
Sulkava
R
R
Raininko
R
R
Tilvis
R
R
D000368:Aged; D000369:Aged, 80 and over; D000375:Aging / Q000502:physiology*; D001288:Attention / Q000502:physiology; D001921:Brain / Q000033:anatomy & histology* / Q000502:physiology*; D015331:Cohort Studies; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008568:Memory / Q000502:physiology; D008606:Mental Processes / Q000502:physiology*; D008875:Middle Aged; D009483:Neuropsychological Tests