Influence of education on the relationship between white matter lesions and cognition.
OBJECTIVE
To test the hypothesis that education level modulates the effects of cerebral white matter hyperintensities (WMH) on cognition in a large population-based study.


METHODS
A total of 845 elderly subjects aged 64 to 76 years who enrolled in a longitudinal study on cognitive decline and vascular aging had an MRI examination. Cognitive functions were assessed by Mini-Mental State Examination, Trail Making Test Part B, Digit Symbol Substitution Test of the Wechsler Adult Intelligence Scale-Revised, Finger Tapping Test, Word Fluency Test, and Raven Progressive Matrix. MRI scans were interpreted visually using a standardized scale for rating WMH.


RESULTS
Severe WMH were present in 17% of the participants who had lower performances on tests involving attention tasks. In participants with a lower level of education, presence of severe WMH was significantly associated with lower cognitive performances. This was found for all cognitive tests. Conversely, in participants with a high level of education, there was no significant association between severity of WMH and level of cognitive functions.


CONCLUSIONS
Education modulates the consequences of WMH on cognition. Participants with a high level of education were protected against the cognitive deterioration related to vascular insults of the brain.
Dufouil
C
C
INSERM Unit 360, Epidemiological Research in Neurology and Psychopathology, Hôpital La Salpêtrière, Paris, France. carole.dufouil@chups.jussieu.fr
Alpérovitch
A
A
Tzourio
C
C
D000368:Aged; D000375:Aging / Q000502:physiology; D001925:Brain Damage, Chronic / Q000175:diagnosis* / Q000453:epidemiology*; D002561:Cerebrovascular Disorders / Q000175:diagnosis* / Q000453:epidemiology*; D003071:Cognition / Q000502:physiology; D003072:Cognition Disorders / Q000453:epidemiology*; D015331:Cohort Studies; D003430:Cross-Sectional Studies; D004522:Educational Status; D005260:Female; D005500:Follow-Up Studies; D005602:France / Q000453:epidemiology; D006801:Humans; D008137:Longitudinal Studies; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D009483:Neuropsychological Tests / Q000706:statistics & numerical data; D014652:Vascular Diseases / Q000453:epidemiology