title: Hyperglycemia is associated with relatively lower lean body mass in older adults.
abstract: OBJECTIVE
  Older adults with known diabetes are vulnerable to accelerated loss of lean body mass. However, the relationship of hyperglycemia per se with lean body mass is not fully understood. We sought to examine the independent relationship of hyperglycemia with relative lean body mass in older persons without a reported history of diabetes.
  
  
  METHODS
  Cross-sectional nationally representative survey.
  
  
  METHODS
  United States.
  
  
  METHODS
  We studied U.S. adults >50 years without known diabetes (n=5434) in the National Health and Nutrition Examination Survey (1999-2004).
  
  
  METHODS
  In linear regression models, we studied the relationship of measured HbA1c (<5.0%, 5.0-5.4%, 5.5-5.9%, 6.0-6.4%, ≥6.5%) with percent lean body mass, measured by dual-energy x-ray absorptiometry, after accounting for potential confounders.
  
  
  RESULTS
  Among older U.S. men and women, progressively higher HbA1c was associated with relatively lower total, appendicular, and trunk percent lean mass, independent of demographics and height (all p<0.05). Accounting for physical activity, C-reactive protein, and diabetes-related comorbidities (heart disease, peripheral arterial disease, arthritis, neuropathy, hip fracture, amputation, cancer, pulmonary disease), undiagnosed diabetes (i.e. HbA1c ≥6.5%) versus reference (<5.0%) in both men and women was associated with lower total (-3.5±0.8% and -2.9±0.8%), appendicular (-1.8±0.5% and -1.2±0.4%), and trunk percent lean mass (-1.2±0.4% and -1.3±0.5%), respectively (all p<0.05). Persons at increased risk for diabetes (i.e. HbA1c 6.0-6.4%) also had significant decrements at these sites versus reference.
  
  
  CONCLUSIONS
  Hyperglycemia is associated with relatively lower lean mass in a nationally representative population of older adults without history of diabetes. Future longitudinal studies are needed to investigate the relationship of hyperglycemia with the accelerated decline of skeletal muscle mass in older persons.
authors.affiliation: Dr. Rita Rastogi Kalyani, Division of Endocrinology, Diabetes, and Metabolism, Department of Medicine, Johns Hopkins University School of Medicine, 1830 East Monument Street, Suite 333, Baltimore, Maryland 21287, Tel: (410) 502-6888, Fax: (410) 955-8172, E-mail: rrastogi@jhmi.edu.
authors.forename: Rita R
authors.initials: RR
authors.lastname: Kalyani
authors.forename: Y
authors.initials: Y
authors.lastname: Tra
authors.forename: J M
authors.initials: JM
authors.lastname: Egan
authors.forename: L
authors.initials: L
authors.lastname: Ferrucci
authors.forename: F
authors.initials: F
authors.lastname: Brancati
mesh_terms: D015502:Absorptiometry, Photon; D000368:Aged; D000369:Aged, 80 and over; D001823:Body Composition; D001835:Body Weight; D003430:Cross-Sectional Studies; D048909:Diabetes Complications / Q000503:physiopathology; D005260:Female; D006442:Glycated Hemoglobin / Q000032:analysis; D006801:Humans; D006943:Hyperglycemia / Q000150:complications / Q000503:physiopathology*; D008297:Male; D008875:Middle Aged; D018482:Muscle, Skeletal / Q000033:anatomy & histology*; D009749:Nutrition Surveys; D009929:Organ Size; D014481:United States
chemical_list: D006442:Glycated Hemoglobin; C517652:hemoglobin A1c protein, human