title: Sex differences in brain aging: a quantitative magnetic resonance imaging study.
abstract: BACKGROUND
  Little is known about the effect of sex on age-related changes in brain structure.
  
  
  METHODS
  Quantitative magnetic resonance imaging of the brain was performed in 330 elderly (age range, 66-96 years) volunteers living independently in the community, all of whom were participants in the Cardiovascular Health Study. Blinded measurements of global and regional brain size were made from T1-weighted axial images by means of computer-assisted edge detection and trace methods. High measurement reliabilities were obtained.
  
  
  RESULTS
  Age-specific changes in brain size were significantly greater in men than women for the peripheral (sulcal) cerebrospinal fluid volume, the lateral (sylvian) fissure cerebrospinal fluid volume, and the parieto-occipital region area. Main effects of age were observed for all the remaining brain regions examined (cerebral hemisphere volume, frontal region area, temporoparietal region area, lateral ventricular volume, and third ventricle volume), but these effects were similar in men and women. Asymmetries in brain structures were not affected by aging in either sex.
  
  
  CONCLUSIONS
  Our results are generally consistent with the few published studies on sex differences in brain aging and suggest that, for at least some structures, aging effects may be more apparent in men than women. The neurobiological bases and functional correlates of these sex differences require further investigation.
authors.affiliation: Department of Psychiatry, Henry Ford Health System, Detroit, Mich 48202, USA. ecoffey1@hfhs.org
authors.forename: C E
authors.initials: CE
authors.lastname: Coffey
authors.forename: J F
authors.initials: JF
authors.lastname: Lucke
authors.forename: J A
authors.initials: JA
authors.lastname: Saxton
authors.forename: G
authors.initials: G
authors.lastname: Ratcliff
authors.forename: L J
authors.initials: LJ
authors.lastname: Unitas
authors.forename: B
authors.initials: B
authors.lastname: Billig
authors.forename: R N
authors.initials: RN
authors.lastname: Bryan
mesh_terms: D017677:Age Distribution; D000368:Aged; D000369:Aged, 80 and over; D000375:Aging / Q000502:physiology*; D001284:Atrophy / Q000473:pathology; D001921:Brain / Q000473:pathology*; D002555:Cerebrospinal Fluid / Q000502:physiology; D003936:Diagnosis, Computer-Assisted; D005260:Female; D006304:Health Status; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D012044:Regression Analysis; D012727:Sex Characteristics; D017678:Sex Distribution