A recent study conducted at the Johns Hopkins School of Medicine and published in the Journal of the Endocrine Society assessed the relationship between lean body mass with aging and to the development of diabetes in men and women. 871 men and 984 women who were participants of the Baltimore Longitudinal Study of Aging with a median follow-up of seven years and were without diabetes at baseline were screened for the study.

      Participants underwent DXA measurements to assess total body composition, fat mass, fat-free mass and bone mineral content for total body and lower extremities. Participants were stratified by quartiles for each baseline body composition measure. Percentage of total lean body mass quartile cutoffs for men of was 43.6% to 62.8%, 62.9% to 67.7%, 67.9% to 72.8% and 72.8% to 91.5%. Percentage of total lean body mass quartile cutoffs for women was 37.3% to 52.24%, 52.34% to 57.6%, 57.6% to 62.2%, and 62.2% to 86.6%. Cox proportional hazard model was used with age as timeline to analyze the incidence of diabetes. Lean body mass measurements were updated at each follow-up visit.

      The study observed that men and women with a higher percentage of total lean body mass had lower fasting and 2-hour glucose measurements, and a lower prevalence of prediabetes at baseline (P = .01 for all). Among men, comparing highest to lowest quartiles, the percentage of total lean body mass (HR=0.46, 95% CI=0.22-0.97), percentage leg lean mass (HR=0.38,0.15-0.96) and lean: fat mass ratio (HR=0.39,0.17-0.89) were found to be inversely associated with the incidence of diabetes after counting for race, and attenuated after adjustment for height and weight. Interchangeably, absolute total lean body mass was found to be positively associated with incident diabetes among men and women. There was no relationship observed with muscle strength or quality with incidence of diabetes.

      The researchers arrived at the concluding remark that relatively lower lean body mass with aging is associated with incident diabetes in men but not in women and are partially related to anthropometrics.