title: Cerebral amyloid angiopathy burden associated with leukoaraiosis: a positron emission tomography/magnetic resonance imaging study.
abstract: OBJECTIVE
  We hypothesized that vascular amyloid contributes to chronic brain ischemia, therefore amyloid burden measured by Pittsburgh compound B retention on positron emission tomography (PiB PET) would correlate with the extent of magnetic resonance imaging (MRI) white matter hyperintensities (WMH; or leukoaraiosis) in patients with high vascular amyloid deposition (cerebral amyloid angiopathy [CAA]) but not in patients with high parenchymal amyloid deposition (Alzheimer disease [AD]; mild cognitive impairment [MCI]) or in healthy elderly (HE) subjects.
  
  
  METHODS
  Forty-two nondemented CAA patients, 50 HE subjects, and 43 AD/MCI patients had brain MRI and PiB PET. Multivariate linear regression was used to assess the independent association between PiB retention and white matter disease volume, controlling for age, gender, apolipoprotein E genotype, and vascular risk factors within each group.
  
  
  RESULTS
  CAA patients were younger than HE and AD subjects (68 ± 10 vs 73.3 ± 7 and 74 ± 7.4, p < 0.01) but had higher amounts of WMH (median = 21 vs 3.2 and 10.8 ml, respectively, p < 0.05 for both comparisons). Global PiB retention and WMH showed strong correlation (rho = 0.52, p < 0.001) in the CAA group but not in HE or AD. These associations did not change in the multivariate models. Lobar microbleed count, another marker of CAA severity, also remained as an independent predictor of WMH volume.
  
  
  CONCLUSIONS
  Our results indicate that amyloid burden in CAA subjects (with primarily vascular amyloid) but not AD subjects (with primarily parenchymal amyloid) independently correlates with WMH volume. These findings support the idea that vascular amyloid burden directly contributes to chronic cerebral ischemia and highlights the possible utility of amyloid imaging as a marker of CAA severity.
authors: Hemorrhagic Stroke Research Center, Department of Neurology, Massachusetts General Hospital, Harvard Medical School, Boston, MA; Department of Biostatistics, Harvard School of Public Health, Boston, MA.
authors: M Edip
authors: ME
authors: Gurol
authors: Anand
authors: A
authors: Viswanathan
authors: Christopher
authors: C
authors: Gidicsin
authors: Trey
authors: T
authors: Hedden
authors: Sergi
authors: S
authors: Martinez-Ramirez
authors: Andrew
authors: A
authors: Dumas
authors: Anastasia
authors: A
authors: Vashkevich
authors: Alison M
authors: AM
authors: Ayres
authors: Eitan
authors: E
authors: Auriel
authors: Ellis
authors: E
authors: van Etten
authors: Alex
authors: A
authors: Becker
authors: Jeremy
authors: J
authors: Carmasin
authors: Kristin
authors: K
authors: Schwab
authors: Jonathan
authors: J
authors: Rosand
authors: Keith A
authors: KA
authors: Johnson
authors: Steven M
authors: SM
authors: Greenberg
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D000544:Alzheimer Disease / Q000000981:diagnostic imaging / Q000473:pathology; D000814:Aniline Compounds; D053327:Apolipoprotein E4 / Q000235:genetics; D016657:Cerebral Amyloid Angiopathy / Q000150:complications / Q000000981:diagnostic imaging / Q000473:pathology; D003072:Cognition Disorders / Q000000981:diagnostic imaging / Q000209:etiology / Q000473:pathology; D005260:Female; D006801:Humans; D049292:Leukoaraiosis / Q000150:complications / Q000000981:diagnostic imaging / Q000473:pathology; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D049268:Positron-Emission Tomography; D018709:Statistics, Nonparametric; D013844:Thiazoles
chemical_list: C475519:2-(4'-(methylamino)phenyl)-6-hydroxybenzothiazole; D000814:Aniline Compounds; D053327:Apolipoprotein E4; D013844:Thiazoles