title: Cerebral microbleeds in the population based AGES-Reykjavik study: prevalence and location.
abstract: OBJECTIVE
  Incidental foci of signal loss suggestive of cerebral microbleeds (CMBs) are frequent findings on gradient echo T2* weighted MRI (T2* MRI) of patients with haemorrhagic or ischaemic stroke. There are few prevalence data on older populations. This paper reports on the prevalence and location of CMBs in a community based cohort of older men and women (born 1907-1935) who participated in the Age Gene/Environment Susceptibility (AGES)-Reykjavik Study, a population based cohort study that followed the Reykjavik Study
  
  
  METHODS
  As part of the examination, 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% to 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) in both men (p = 0.006) and women (p = 0.007). CMBs were located in the cerebral lobes (70%), the basal ganglia region (10.5%) and infratentorium (18.6%). Having a CMB was significantly associated with a homozygote Apo E epsilon4epsilon4 genotype (p = 0.01).
  
  
  CONCLUSIONS
  Cerebral microbleeds are common in older persons. The association with homozygote Apo E epsilon4 genotype and finding a relative predominance in the parietal lobes might indicate an association with amyloid angiopathy.
authors.affiliation: Department of Neurology, Landspitali University Hospital, C12, Fossvogur, 108 Reykjavik, Iceland. sigurls@landspitali.is
authors.forename: S
authors.initials: S
authors.lastname: Sveinbjornsdottir
authors.forename: S
authors.initials: S
authors.lastname: Sigurdsson
authors.forename: T
authors.initials: T
authors.lastname: Aspelund
authors.forename: O
authors.initials: O
authors.lastname: Kjartansson
authors.forename: G
authors.initials: G
authors.lastname: Eiriksdottir
authors.forename: B
authors.initials: B
authors.lastname: Valtysdottir
authors.forename: O L
authors.initials: OL
authors.lastname: Lopez
authors.forename: M A
authors.initials: MA
authors.lastname: van Buchem
authors.forename: P V
authors.initials: PV
authors.lastname: Jonsson
authors.forename: V
authors.initials: V
authors.lastname: Gudnason
authors.forename: L J
authors.initials: LJ
authors.lastname: Launer
mesh_terms: D000368:Aged; D053327:Apolipoprotein E4 / Q000235:genetics; D001479:Basal Ganglia / Q000473:pathology*; D002543:Cerebral Hemorrhage / Q000453:epidemiology* / Q000235:genetics / Q000473:pathology*; D005260:Female; D005838:Genotype; D006801:Humans; D007055:Iceland; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D015995:Prevalence; D012307:Risk Factors; D012737:Sex Factors
chemical_list: D053327:Apolipoprotein E4