title: Association between insulin resistance and lean mass loss and fat mass gain in older men without diabetes mellitus.
abstract: OBJECTIVE
  To examine the associations between insulin resistance and changes in body composition in older men without diabetes mellitus.
  
  
  METHODS
  Longitudinal cohort study of older men participating in the Osteoporotic Fractures in Men (MrOS) study.
  
  
  METHODS
  Six U.S. clinical centers.
  
  
  METHODS
  Three thousand one hundred thirty-two ambulatory men aged 65 and older at baseline.
  
  
  METHODS
  Baseline insulin resistance was calculated for men without diabetes mellitus using the homeostasis model assessment of insulin resistance (HOMA-IR). Total lean, appendicular lean, total fat, and truncal fat mass were measured using dual energy X-ray absorptiometry scans at baseline and 4.6 ± 0.3 years later in 3,132 men with HOMA-IR measurements.
  
  
  RESULTS
  There was greater loss of weight, total lean mass, and appendicular lean mass and less gain in total fat mass and truncal fat mass with increasing quartiles of HOMA-IR (P<.001 for trend). Insulin-resistant men in the highest quartile had higher odds of 5% or more loss of weight (odds ratio (OR)=1.88, 95% confidence interval (CI)=1.46-2.43), total lean mass (OR=2.09, 95% CI=1.60-2.73) and appendicular lean mass (OR=1.57, 95% CI=1.27-1.95) and lower odds of 5% or more gain in total fat mass (OR=0.56, 95% CI=0.45-0.68) and truncal fat mass (OR=0.52, 95% CI=0.42-0.64) than those in the lowest quartile. These findings remained significant after accounting for age, site, baseline weight, physical activity, and change in physical activity. These associations were also independent of other metabolic syndrome features and medications.
  
  
  CONCLUSIONS
  Greater lean mass loss and lower fat mass gain occurred in insulin-resistant men without diabetes mellitus than in insulin-sensitive men. Insulin resistance may accelerate age-related sarcopenia.
authors: Division of Endocrinology, Diabetes and Clinical Nutrition, Department of Medicine, Oregon Health & Science University, Portland, OR 97239, USA. leechr@ohsu.edu
authors: Christine G
authors: CG
authors: Lee
authors: Edward J
authors: EJ
authors: Boyko
authors: Elsa S
authors: ES
authors: Strotmeyer
authors: Cora E
authors: CE
authors: Lewis
authors: Peggy Mannen
authors: PM
authors: Cawthon
authors: Andrew R
authors: AR
authors: Hoffman
authors: Susan A
authors: SA
authors: Everson-Rose
authors: Elizabeth
authors: E
authors: Barrett-Connor
authors: Eric S
authors: ES
authors: Orwoll
mesh_terms: D015502:Absorptiometry, Photon; D000273:Adipose Tissue / Q000033:anatomy & histology*; D000368:Aged; D001823:Body Composition; D001835:Body Weight; D015331:Cohort Studies; D003710:Demography; D006801:Humans; D007333:Insulin Resistance / Q000502:physiology*; D008137:Longitudinal Studies; D008297:Male