title: Hemodynamic correlates of transient cognitive impairment after transient ischemic attack and minor stroke: A transcranial Doppler study.
abstract: Transient cognitive impairment (TCI) on the Mini Mental State Evaluation score is common after transient ischemic attack/minor stroke and might identify patients at increased risk of dementia. We aimed to replicate TCI using the Montreal Cognitive Assessment (MoCA), compare it with persistent Mild Cognitive Impairment (PMCI), and to determine whether global cerebral hemodynamic changes could explain transient impairment.
  
  
  
  Consecutive patients with transient ischemic attack/minor stroke (NIHSS ≤ 3) were assessed with the MoCA and transcranial Doppler ultrasound acutely and at 1 month. We compared patients with TCI (baseline MoCA < 26 with ≥ 2 points increase at 1 month), PMCI (MoCA < 26 with < 2 points increase), and no cognitive impairment (NCI; MoCA ≥ 26).
  
  
  
  Of 326 patients, 46 (14.1%) had PMCI, 98 (30.1%) TCI, and 182 (55.8%) NCI. At baseline, TCI patients had higher systolic blood pressure (150.95 ± 21.52 vs 144.86 ± 22.44 mmHg, p = 0.02) and lower cerebral blood flow velocities, particularly end-diastolic velocity (30.16 ± 9.63 vs 35.02 ± 9.01 cm/s, p < 0.001) and mean flow velocity (48.95 ± 12.72 vs 54 ± 12.46 cm/s, p = 0.001) than those with NCI, but similar clinical and hemodynamic profiles to those with PMCI. Systolic BP fell between baseline and 1 month (mean reduction = 14.01 ± 21.26 mmHg) and end-diastolic velocity and mean flow velocity increased (mean increase = + 2.42 ± 6.41 and 1.89 ± 8.77 cm/s, respectively), but these changes did not differ between patients with TCI, PMCI, and NCI.
  
  
  
  TCI is detectable with the MoCA after transient ischemic attack and minor stroke and has similar clinical and hemodynamic profile to PMCI. However, TCI does not appear to be due to exaggerated acute reversible global hemodynamic changes.
authors.affiliation: Nuffield Department of Clinical Neurosciences, University of Oxford, Oxford, UK sara.mazzucco@ndcn.ox.ac.uk.
authors.forename: Sara
authors.initials: S
authors.lastname: Mazzucco
authors.affiliation: Nuffield Department of Clinical Neurosciences, University of Oxford, Oxford, UK.
authors.forename: Linxin
authors.initials: L
authors.lastname: Li
authors.affiliation: Nuffield Department of Clinical Neurosciences, University of Oxford, Oxford, UK.
authors.forename: Maria A
authors.initials: MA
authors.lastname: Tuna
authors.affiliation: Nuffield Department of Clinical Neurosciences, University of Oxford, Oxford, UK.
authors.forename: Sarah T
authors.initials: ST
authors.lastname: Pendlebury
authors.affiliation: Nuffield Department of Clinical Neurosciences, University of Oxford, Oxford, UK.
authors.forename: Rose
authors.initials: R
authors.lastname: Wharton
authors.affiliation: Nuffield Department of Clinical Neurosciences, University of Oxford, Oxford, UK.
authors.forename: Peter M
authors.initials: PM
authors.lastname: Rothwell
mesh_terms: D000368:Aged; D001921:Brain / Q000098:blood supply / Q000000981:diagnostic imaging* / Q000503:physiopathology; D002560:Cerebrovascular Circulation; D060825:Cognitive Dysfunction / Q000000981:diagnostic imaging* / Q000209:etiology / Q000503:physiopathology; D005500:Follow-Up Studies; D006439:Hemodynamics; D006801:Humans; D015994:Incidence; D002546:Ischemic Attack, Transient / Q000150:complications / Q000000981:diagnostic imaging* / Q000503:physiopathology / Q000523:psychology; D008137:Longitudinal Studies; D008875:Middle Aged; D020521:Stroke / Q000150:complications / Q000000981:diagnostic imaging* / Q000503:physiopathology / Q000523:psychology; D013997:Time Factors; D017585:Ultrasonography, Doppler, Transcranial
keywords: Transcranial Doppler; blood flow velocity; cerebrovascular diseases; cognitive impairment; dementia; stroke