Critical illness-associated cerebral microbleeds
Fanou EM, Coutinho JM, Shannon P, et al.
Stroke 2017; 48:1085-1087.
To determine whether microbleeds, and more specifically microbleed count and location, are associated with an increased risk for cognitive impairment and dementia in the general population.
The Rotterdam Study, a prospective population-based study set in the general community, assessed the presence, number, and location of microbleeds at baseline (August 2005 to December 2011) on magnetic resonance imaging studies of the brain in 4841 participants 45 years or older. Participants underwent neuropsychological testing at 2 points a mean (SD) of 5.9 (0.6) years apart and were followed up for incident dementia throughout the study period until January 1, 2013. The association of microbleeds with cognitive decline and dementia was studied using multiple linear regression, linear mixed-effects modeling, and Cox proportional hazards.
In total, 3257 participants (1758 women [54.7%]; mean [SD] age, 59.6 [7.8] years) underwent baseline and follow-up cognitive testing. Microbleed prevalence was 15.3% (median [interquartile range] count, 1 [1-88]). The presence of more than 4 microbleeds was associated with cognitive decline. Lobar (with or without cerebellar) microbleeds were associated with a decline in executive functions (mean difference in z score, -0.31; 95% CI, -0.51 to -0.11; P = .003), information processing (mean difference in z score, -0.44; 95% CI, -0.65 to -0.22; P < .001), and memory function (mean difference in z score, -0.34; 95% CI, -0.64 to -0.03; P = .03), whereas microbleeds in other brain regions were associated with a decline in information processing and motor speed (mean difference in z score, -0.61; 95% CI, -1.05 to -0.17; P = .007). After a mean (SD) follow-up of 4.8 (1.4) years, 72 participants developed dementia, of whom 53 had Alzheimer dementia. The presence of microbleeds was associated with an increased risk for dementia after adjustment for age, sex, and educational level (hazard ratio, 2.02; 95% CI, 1.25-3.24), including Alzheimer dementia (hazard ratio, 2.10; 95% CI, 1.21-3.64).
CONCLUSIONS AND RELEVANCE:
In the general population, a high microbleed count was associated with an increased risk for cognitive deterioration and dementia. Microbleeds thus mark the presence of diffuse vascular and neurodegenerative brain damage.
This reference is now included in the neurochecklist: