O2‐04‐04: Cerebral microbleeds are associated with worse cognitive function: The Rotterdam Scan Study

Vascular pathology has shown to play a prominent role in impaired cognitive function. Microbleeds are frequently found in the general elderly population and may reflect underlying vascular disease, in particular cerebral amyloid angiopathy (CAA) and hypertensive vasculopathy. Their role in cognitive function in the general elderly population, however, is unknown. We investigated the association between microbleeds and performance in multiple cognitive domains. This study is based on 3979 nondemented persons (mean age, 60.3 years) from the population-based Rotterdam Scan Study. We used linear regression models to estimate the association of microbleeds with different cognitive domains. Separate categories were made for 1 microbleed, 2-5 microbleeds and >5 microbleeds. We stratified analyses for location of microbleeds and APOEe4 allele status. Additional adjustments were made for vascular risk factors, brain atrophy and other markers of small vessel disease. Main outcome measures were performance on MMSE-score and neuropsychological tests in the following cognitive domains: memory, executive function, information processing speed, global cognition and motor speed. Presence of more than 5 microbleeds was associated with worse performance in all cognitive domains, except memory. These associations were most marked in participants with strictly lobar microbleeds, whereas associations were much weaker or absent for deep or infratentorial microbleeds. After adjustment for brain atrophy, vascular risk factors or other markers of small vessel disease, the associations attenuated only marginally. Presence of multiple microbleeds, especially in a strictly lobar location, is associated with worse performance on tests measuring cognitive function, even after adjustments for vascular risk factors and other markers of small vessel disease. These results suggest an independent role for microbleeds in cognitive impairment.