title: Aortic reservoir characteristics and brain structure in people with type 2 diabetes mellitus; a cross sectional study.
abstract: BACKGROUND
  Central hemodynamics help to maintain appropriate cerebral and other end-organ perfusion, and may be altered with ageing and type 2 diabetes mellitus (T2DM). We aimed to determine the associations between central hemodynamics and brain structure at rest and during exercise in people with and without T2DM.
  
  
  METHODS
  In a sample of people with T2DM and healthy controls, resting and exercise measures of aortic reservoir characteristics (including excess pressure integral [P(excess)]) and other central hemodynamics (including augmentation index [AIx] and aortic pulse wave velocity [aPWV]) were recorded. Brain volumes (including gray matter volume [GMV] and white matter lesions [WML]) were derived from magnetic resonance imaging (MRI) scans. Multivariable linear regression was used to study the associations of hemodynamic variables with brain structure in the two groups adjusting for age, sex, daytime systolic BP (SBP) and heart rate.
  
  
  RESULTS
  There were 37 T2DM (63 ± 9 years; 47% male) and 37 healthy individuals (52 ± 8 years; 51% male). In T2DM, resting aPWV was inversely associated with GMV (standardized β = -0.47, p = 0.036). In healthy participants, resting P(excess) was inversely associated with GMV (β = -0.23, p = 0.043) and AIx was associated with WML volume (β = 0.52, p = 0.021). There were no associations between exercise hemodynamics and brain volumes in either group.
  
  
  CONCLUSIONS
  Brain atrophy is associated with resting aortic stiffness in T2DM, and resting P(excess) in healthy individuals. Central vascular mechanisms underlying structural brain changes may differ between healthy individuals and T2DM.
authors.forename: Rachel E D
authors.initials: RE
authors.lastname: Climie
authors.forename: Velandai
authors.initials: V
authors.lastname: Srikanth
authors.forename: Richard
authors.initials: R
authors.lastname: Beare
authors.forename: Laura J
authors.initials: LJ
authors.lastname: Keith
authors.forename: James
authors.initials: J
authors.lastname: Fell
authors.forename: Justin E
authors.initials: JE
authors.lastname: Davies
authors.forename: James E
authors.initials: JE
authors.lastname: Sharman
mesh_terms: D000328:Adult; D000368:Aged; D062186:Arterial Pressure / Q000502:physiology; D001921:Brain / Q000473:pathology*; D003430:Cross-Sectional Studies; D003924:Diabetes Mellitus, Type 2 / Q000175:diagnosis* / Q000503:physiopathology*; D005260:Female; D006439:Hemodynamics / Q000502:physiology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D059289:Vascular Stiffness / Q000502:physiology*