title: Blood viscosity in subcortical vascular mild cognitive impairment with versus without cerebral amyloid burden.
abstract: BACKGROUND
  Subcortical vascular dementia (SVaD) is a common form of dementia, attributed to ischemic small-vessel disease. Blood viscosity (BV) may contribute to the pathophysiology of SVaD. However, SVaD patients with coexisting amyloid deposition may not show differences in BV because their small-vessel disease may result from amyloid angiopathy independently of BV. We, therefore, hypothesized that BV might show different changes compared with control subjects in subcortical vascular mild cognitive impairment (svMCI) that refers to the prodromal stage of SVaD according to cerebral amyloid burden detected by the [(11)C] Pittsburgh compound B (PiB) PET (positron emission tomography), and apolipoprotein 4 (ApoE4) genotype (a known risk factor for vascular and parenchymal amyloid).
  
  
  METHODS
  Our subjects consisted of 33 healthy normal controls (NC), 28 patients with PiB(-) svMCI, and 12 with PiB(+) svMCI. They underwent scanning capillary tube viscometer measuring BV during systolic and diastolic phases.
  
  
  RESULTS
  Compared with the NC group, the PiB(-) svMCI group showed increased diastolic blood viscosity (DBV) but no difference in systolic blood viscosity (SBV). By contrast, there was no significant difference in SBV and DBV between the NC and PiB(+) svMCI groups. Within the PiB(+) svMCI group, ApoE4(-) subgroup showed increased DBV compared with the ApoE4(+) subgroup.
  
  
  CONCLUSIONS
  Increased DBV is an important contributor to the development of "pure" svMCI (ie, without cerebral amyloid deposition). The relationship between BV and PiB(+) svMCI differed according to ApoE genotype, suggesting that the pathogenesis of PiB(+) svMCI might also be heterogeneous.
authors.affiliation: Department of Neurology, Sungkyunkwan University School of Medicine, Samsung Medical Center, Seoul, Korea.
authors.forename: Hyun J
authors.initials: HJ
authors.lastname: Noh
authors.affiliation: Department of Neurology, Sungkyunkwan University School of Medicine, Samsung Medical Center, Seoul, Korea. Electronic address: sangwonseo@empal.com.
authors.forename: Sang W
authors.initials: SW
authors.lastname: Seo
authors.affiliation: Department of Bio and Brain Engineering, Korea Advanced Institute of Science and Technology, Daejeon, Korea.
authors.forename: Yong
authors.initials: Y
authors.lastname: Jeong
authors.affiliation: Department of Cardiology, Sungkyunkwan University School of Medicine, Samsung Medical Center, Seoul, Korea.
authors.forename: Jeong E
authors.initials: JE
authors.lastname: Park
authors.affiliation: Department of Neurology, Inha University School of Medicine, Incheon, Korea.
authors.forename: Geon H
authors.initials: GH
authors.lastname: Kim
authors.affiliation: Department of Neurology, Gachon University Gil Medical Center, Incheon, Korea.
authors.forename: Young
authors.initials: Y
authors.lastname: Noh
authors.affiliation: Department of Neurology, Sungkyunkwan University School of Medicine, Samsung Medical Center, Seoul, Korea.
authors.forename: Hanna
authors.initials: H
authors.lastname: Cho
authors.affiliation: Department of Neurology, Sungkyunkwan University School of Medicine, Samsung Medical Center, Seoul, Korea.
authors.forename: Hee J
authors.initials: HJ
authors.lastname: Kim
authors.affiliation: Department of Neurology, Inha University School of Medicine, Incheon, Korea.
authors.forename: Cindy W
authors.initials: CW
authors.lastname: Yoon
authors.affiliation: Department of Neurology, Sungkyunkwan University School of Medicine, Samsung Medical Center, Seoul, Korea.
authors.forename: Byong S
authors.initials: BS
authors.lastname: Ye
authors.affiliation: Department of Brain Repair and Rehabilitation, University College of London Institute of Neurology, Queen Square, London, UK.
authors.forename: David J
authors.initials: DJ
authors.lastname: Werring
authors.affiliation: Department of Neurology, Sungkyunkwan University School of Medicine, Samsung Medical Center, Seoul, Korea.
authors.forename: Duk L
authors.initials: DL
authors.lastname: Na
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D000814:Aniline Compounds; D053327:Apolipoprotein E4 / Q000235:genetics; D001809:Blood Viscosity; D016022:Case-Control Studies; D016657:Cerebral Amyloid Angiopathy / Q000097:blood* / Q000175:diagnosis / Q000235:genetics; D060825:Cognitive Dysfunction / Q000097:blood* / Q000175:diagnosis / Q000235:genetics; D015140:Dementia, Vascular / Q000097:blood* / Q000175:diagnosis / Q000235:genetics; D005260:Female; D020022:Genetic Predisposition to Disease; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D009483:Neuropsychological Tests; D010641:Phenotype; D049268:Positron-Emission Tomography; D011237:Predictive Value of Tests; D011446:Prospective Studies; D019275:Radiopharmaceuticals; D012307:Risk Factors; D013844:Thiazoles
chemical_list: C475519:2-(4'-(methylamino)phenyl)-6-hydroxybenzothiazole; D000814:Aniline Compounds; D053327:Apolipoprotein E4; D019275:Radiopharmaceuticals; D013844:Thiazoles
keywords: Hemodynamic; MRI; amyloid; artherosclerosis; vascular dementia