title: Adiposity estimated using dual energy X-ray absorptiometry and body mass index and its association with cognition in elderly adults.
abstract: OBJECTIVE
  To determine whether obesity, estimated according to body mass index (BMI), waist circumference, and body fat and abdominal fat assessed using dual-energy X-ray absorptiometry (DEXA), was associated with cognitive performance.
  
  
  METHODS
  Cross-sectional.
  
  
  METHODS
  Community based.
  
  
  METHODS
  Individuals aged 74-94 (N = 406).
  
  
  METHODS
  BMI, waist circumference, body fat, and abdominal fat were assessed using DEXA. Cognitive performance was assessed using a comprehensive neuropsychological battery.
  
  
  RESULTS
  When categorized using BMI, overweight individuals had higher global cognitive function and executive function scores than normal-weight individuals. This relationship did not differ according to sex. When categorized according to DEXA, there were no relationships between body fat and cognitive function in the whole group, but women in the middle and highest tertiles of DEXA body fat had better executive function than those in the lowest tertile. Men in the middle tertile of DEXA body fat had significantly better executive function and memory than those in the lowest tertile. BMI had greater power to predict executive function than DEXA body fat. No significant associations were found between cognition and estimates of abdominal adiposity.
  
  
  CONCLUSIONS
  This study found an association between being overweight and better executive function in elderly adults; this association was stronger for the simpler BMI than the more-elaborate DEXA measures.
authors.affiliation: Department of Developmental Disability Neuropsychiatry, School of Psychiatry, University of New South Wales, Sydney, New South Wales, Australia; Centre for Healthy Brain Ageing, School of Psychiatry, University of New South Wales, Sydney, New South Wales, Australia.
authors.forename: Evelyn
authors.initials: E
authors.lastname: Smith
authors.forename: Phoebe E
authors.initials: PE
authors.lastname: Bailey
authors.forename: John
authors.initials: J
authors.lastname: Crawford
authors.forename: Katherine
authors.initials: K
authors.lastname: Samaras
authors.forename: Bernhard T
authors.initials: BT
authors.lastname: Baune
authors.forename: Lesley
authors.initials: L
authors.lastname: Campbell
authors.forename: Nicole
authors.initials: N
authors.lastname: Kochan
authors.forename: Jasmine
authors.initials: J
authors.lastname: Menant
authors.forename: Daina L
authors.initials: DL
authors.lastname: Sturnieks
authors.forename: Henry
authors.initials: H
authors.lastname: Brodaty
authors.forename: Perminder
authors.initials: P
authors.lastname: Sachdev
authors.forename: Julian N
authors.initials: JN
authors.lastname: Trollor
mesh_terms: D015502:Absorptiometry, Photon; D050154:Adiposity; D000368:Aged; D000369:Aged, 80 and over; D001823:Body Composition; D015992:Body Mass Index; D003071:Cognition / Q000502:physiology*; D003430:Cross-Sectional Studies; D005260:Female; D006801:Humans; D007407:Interviews as Topic; D008297:Male; D009483:Neuropsychological Tests; D009765:Obesity / Q000503:physiopathology; D050177:Overweight / Q000503:physiopathology; D055105:Waist Circumference
keywords: body mass index; cognition; dual-energy X-ray absorptiometry; elderly; fat mass; obesity