title: Strictly lobar microbleeds are associated with executive impairment in patients with ischemic stroke or transient ischemic attack.
abstract: OBJECTIVE
  Cerebral microbleeds (CMBs) are a marker of small vessel diseases, including hypertensive arteriopathy and cerebral amyloid angiopathy, and may be associated with cognitive impairment. The relationship between CMBs and cognitive function in ischemic cerebrovascular disease remains uncertain. We, therefore, investigated the cognitive impact of CMBs in a cohort of patients with ischemic stroke or transient ischemic attack.
  
  
  METHODS
  All patients underwent detailed and comprehensive neuropsychological testing and standardized MRI, including fluid attenuation inversion recovery, T1, T2, and gradient-recalled echo T2*-weighted sequences. CMBs, white matter changes, lacunes, and territorial cortical infarcts (defined by standardized criteria) were identified, and associations with cognition assessed.
  
  
  RESULTS
  Three hundred twenty patients with a diagnosis of ischemic stroke or transient ischemic attack were included. Of these, 72 (22.5%) had at least 1 CMB. Of all the cognitive domains tested, only executive impairment was more prevalent in patients with CMBs than without (38% versus 25%; P=0.039). In univariate analysis, the presence of strictly lobar (but not deep) CMBs was associated with executive impairment (odds ratio, 2.49; 95% confidence interval, 1.16-5.36; P=0.019). In adjusted multivariate analyses, the presence (OR, 2.34; 95% confidence interval, 1.08-5.09; P=0.031) and number (OR, 1.33; 95% confidence interval, 1.04-1.69; P=0.022) of strictly lobar CMBs were significantly associated with executive impairment. CMBs were not associated with impairment in other cognitive domains.
  
  
  CONCLUSIONS
  Strictly lobar CMBs are independently associated with executive dysfunction in patients with ischemic stroke or transient ischemic attack. Our findings suggest that a microangiopathy related to strictly lobar CMBs (eg, cerebral amyloid angiopathy) contributes to cognitive impairment in this population.
authors.affiliation: Department of Brain Repair and Rehabilitation, National Hospital for Neurology and Neurosurgery, Queen Square, London WC1N 3BG, United Kingdom.
authors.forename: Simone M
authors.initials: SM
authors.lastname: Gregoire
authors.forename: Grit
authors.initials: G
authors.lastname: Scheffler
authors.forename: Hans R
authors.initials: HR
authors.lastname: Jäger
authors.forename: Tarek A
authors.initials: TA
authors.lastname: Yousry
authors.forename: Martin M
authors.initials: MM
authors.lastname: Brown
authors.forename: Constantinos
authors.initials: C
authors.lastname: Kallis
authors.forename: Lisa
authors.initials: L
authors.lastname: Cipolotti
authors.forename: David J
authors.initials: DJ
authors.lastname: Werring
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002545:Brain Ischemia / Q000150:complications / Q000523:psychology*; D056344:Executive Function / Q000502:physiology*; D005260:Female; D006801:Humans; D020300:Intracranial Hemorrhages / Q000150:complications / Q000523:psychology*; D002546:Ischemic Attack, Transient / Q000150:complications / Q000523:psychology*; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D009483:Neuropsychological Tests; D020521:Stroke / Q000150:complications / Q000523:psychology*