Abstract

Background and purpose: Incidental foci of signal loss suggestive of past cerebral microbleeds (CMBs) are frequent findings on gradient echo T2*-weighted MRI (T2*-MRI) of patients with haemorrhagic or ischemic stroke. There are few prevalence data on older populations. We report on the prevalence and location of CMBs in a community-based cohort of older men and women [b. 1907-35], who participated in the AGES-Reykjavik Study, a population based cohort study that followed the Reykjavik Study.

Methods: As a part of the exam, all eligible and consenting cohort members underwent a full brain MRI and blood was drawn for genotyping. Results are based on the first 1962 men (n=820) and women (n=1142), mean age 76 years, with complete MRI and demographic information available.

Results: Evidence of CMBs was found in 218 participants (11.1% (95% CI 9.8%-12.6%)); men had significantly more CMBs than women (14.4% vs. 8.8%; p=0.0002, age adjusted). The prevalence of CMBs increased with age (p=0.0001) both in men (p=0.006) and women (p=0.007). CMBs were located in the cerebral lobes (70%), the basal ganglia region (10.5%) and infratentorial (18.6%). Having a CMB was significantly associated with a homozygote APO E å4å4 genotype (p=0.008).

Conclusion: Cerebral microbleeds are common in older persons. The association with homozygote APO-E å4 genotype and finding a relative predominance in the parietal lobes, might indicate an association with amyloid angiopathy.