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Context Older adults have the greatest burden of diabetes; however, the contribution of age-related muscle loss to its development remains unclear. Objective We assessed the relationship of lean body mass with aging to incident diabetes in community-dwelling adults. Design and Setting We studied participants in the Baltimore Longitudinal Study of Aging with median follow-up of 7 years (range 1-16). Cox proportional hazard models with age as the time scale were used. Time-dependent lean body mass measures were updated at each follow-up visit available. Participants Participants included 871 men and 984 women without diabetes who had  ≥ 1 assessment of body composition using dual x-ray absorptiometry. Main Outcomes Incident diabetes, defined as self-reported history and use of glucose-lowering medications; or fasting plasma glucose ≥ 126 mg/dL and 2-hour oral glucose tolerance test glucose ≥ 200 mg/dL either at the same visit or 2 consecutive visits. Results The baseline mean [standard deviation] age was 58.9  [17.3] years. Men and women with a higher percentage of total lean body mass had lower fasting and 2-hour glucose levels, and less prediabetes (all P  < 0.01). Among men, comparing highest versus lowest quartiles, percentage of total lean body mass (hazard ratio [HR],  0.46; 95% confidence interval, 0.22-0.97), percentage leg lean mass (HR, 0.38; 0.15-0.96), and lean-to-fat mass ratio (HR, 0.39; 0.17-0.89) were inversely associated with incident diabetes after accounting for race and attenuated after adjustment for height and weight. Conversely, absolute total lean body mass was positively associated with incident diabetes among women, with similar trends in men. No associations were observed with muscle strength or quality. Conclusions Relatively lower lean body mass with aging is associated with incident diabetes in men and partially related to anthropometrics, but not so in women. [ABSTRACT FROM AUTHOR]

Background: The current studies were designed to examine the effect of aging and diabetes on the enteroinsular axis.Methods: Healthy young control subjects (n = 10 young; age 23 +/- 1 years; body mass index [BMI] 24 +/- 1 kg/m(2)), healthy elderly subjects (n = 10; age 80 +/- 2 years; BMI 26 +/- 1 kg/m(2)), and elderly patients with type 2 diabetes (n = 10; age 76 +/- 2 years; BMI 26 +/- 2 kg/m(2)) underwent a 3-hour oral glucose tolerance test (glucose dose 40 gm/m(2)).Results: Insulin responses were not different between young controls and elderly patients with diabetes but were significantly lower in elderly patients with diabetes and young controls than in elderly controls (young control: 178 +/- 27 pM; elderly control: 355 +/- 57 pM; elderly diabetes: 177 +/- 30 pM; p <.05 elderly control vs young control and elderly diabetes). Total glucagon-like peptide 1 (GLP-1) responses were not significantly different between young and elderly controls and patients with diabetes (young control: 15 +/- 2 pM; old control: 8 +/- 2 pM; elderly diabetes: 12 +/- 3 pM; p = ns). Active GLP-1 responses were also not different between young and elderly controls and patients with diabetes (young control: 5 +/- 1 pM; old control: 6 +/- 1 pM; elderly diabetes: 7 +/- 1 pM; p = ns). However, the difference between total and active GLP levels was significantly greater in the young controls (young control: 10 +/- 2 pM; old control: 2 +/- 2 pM; elderly diabetes: 4 +/- 2 pM; p <.05, young vs elderly). Glucose-dependent insulinotropic polypeptide responses were not different between young and elderly controls and between elderly controls and patients with diabetes but were significantly higher in elderly patients with diabetes than in young controls (young control: 97 +/- 12 pM; elderly control: 121 +/- 16 pM; elderly diabetes: 173 +/- 27 pM; p <.05, young vs elderly diabetes). Glucagon responses were reduced in elderly controls but were similar in young controls and elderly patients with diabetes (young control: 15 +/- 1 pM; elderly control: 9 +/- 1 pM; elderly diabetes: 16 +/- 1 pM; p <.01 elderly control vs young control and elderly diabetes). Dipeptidyl peptidase IV levels were lower in both elderly controls and patients with diabetes when compared with young controls (young control: 0.17 +/- 0.01; elderly control: 0.15 +/- 0.01; elderly diabetes: 0.15 +/- 0.01 DeltaOD/20 minutes; p <.05, elderly vs young).Conclusions: We conclude that normal aging and diabetes are associated with multiple changes in the enteroinsular axis. [ABSTRACT FROM AUTHOR]