title: Low cerebral blood flow is associated with lower memory function in metabolic syndrome.
abstract: BACKGROUND
  Metabolic syndrome (MetS)--a cluster of cardiovascular risk factors--is linked with cognitive decline and dementia. However, the brain changes underlying this link are presently unknown. In this study, we tested the relationship between MetS, cerebral blood flow (CBF), white matter hyperintensity burden, and gray matter (GM) volume in cognitively healthy late middle-aged adults. Additionally, the extent to which MetS was associated with cognitive performance was assessed.
  
  
  METHODS
  Late middle-aged adults from the Wisconsin Registry for Alzheimer's Prevention (N = 69, mean age = 60.4 years) underwent a fasting blood draw, arterial spin labeling perfusion MRI, T1-weighted MRI, T2FLAIR MRI, and neuropsychological testing. MetS was defined as abnormalities on three or more factors, including abdominal obesity, triglycerides, HDL-cholesterol, blood pressure, and fasting glucose.
  
  
  RESULTS
  Mean GM CBF was 15% lower in MetS compared to controls. Voxel-wise image analysis indicated that the MetS group had lower CBF across a large portion of the cortical surface, with the exception of medial and inferior parts of the occipital and temporal lobes. The MetS group also had lower immediate memory function; a mediation analysis indicated this relationship was partially mediated by CBF. Among the MetS factors, abdominal obesity and elevated triglycerides were most strongly associated with lower CBF.
  
  
  CONCLUSIONS
  The results underscore the importance of reducing the number of cardiovascular risk factors for maintaining CBF and cognition in an aging population.
authors.affiliation: Geriatric Research, Education and Clinical Center, William S. Middleton Memorial Veteran's Hospital, Madison, Wisconsin, USA.
authors.forename: Alex C
authors.initials: AC
authors.lastname: Birdsill
authors.forename: Cynthia M
authors.initials: CM
authors.lastname: Carlsson
authors.forename: Auriel A
authors.initials: AA
authors.lastname: Willette
authors.forename: Ozioma C
authors.initials: OC
authors.lastname: Okonkwo
authors.forename: Sterling C
authors.initials: SC
authors.lastname: Johnson
authors.forename: Guofan
authors.initials: G
authors.lastname: Xu
authors.forename: Jennifer M
authors.initials: JM
authors.lastname: Oh
authors.forename: Catherine L
authors.initials: CL
authors.lastname: Gallagher
authors.forename: Rebecca L
authors.initials: RL
authors.lastname: Koscik
authors.forename: Erin M
authors.initials: EM
authors.lastname: Jonaitis
authors.forename: Bruce P
authors.initials: BP
authors.lastname: Hermann
authors.forename: Asenath
authors.initials: A
authors.lastname: LaRue
authors.forename: Howard A
authors.initials: HA
authors.lastname: Rowley
authors.forename: Sanjay
authors.initials: S
authors.lastname: Asthana
authors.forename: Mark A
authors.initials: MA
authors.lastname: Sager
authors.forename: Barbara B
authors.initials: BB
authors.lastname: Bendlin
mesh_terms: D000367:Age Factors; D000368:Aged; D000544:Alzheimer Disease / Q000209:etiology / Q000503:physiopathology; D053327:Apolipoprotein E4 / Q000378:metabolism; D001786:Blood Glucose / Q000378:metabolism; D001794:Blood Pressure; D001921:Brain / Q000033:anatomy & histology; D002560:Cerebrovascular Circulation / Q000502:physiology*; D008076:Cholesterol, HDL / Q000097:blood; D003072:Cognition Disorders / Q000209:etiology / Q000503:physiopathology*; D003430:Cross-Sectional Studies; D005215:Fasting; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008568:Memory / Q000502:physiology*; D024821:Metabolic Syndrome / Q000150:complications / Q000503:physiopathology*; D008875:Middle Aged; D009483:Neuropsychological Tests; D009929:Organ Size; D012039:Regional Blood Flow; D012307:Risk Factors; D013113:Spin Labels; D014280:Triglycerides / Q000097:blood; D014922:Wisconsin
chemical_list: D053327:Apolipoprotein E4; D001786:Blood Glucose; D008076:Cholesterol, HDL; D013113:Spin Labels; D014280:Triglycerides