Age-Related Changes in Body Composition and Bone Mineral Density and Their Relationship with the Duration of Diabetes and Glycaemic Control in Type 2 Diabetes

PURPOSE: To investigate age-related changes in body composition (BC) and bone mineral density (BMD) in type 2 diabetes (T2D) and analyse whether diabetes duration or glycaemic control affects these factors. PATIENTS AND METHODS: We enrolled 1474 hospitalized T2D patients (817 males and 657 females; 45–85 years). BC and BMD were assessed by dual-energy X-ray absorptiometry (DEXA). Patients were stratified into age groups: 45–54, 55–64, 65–74, and ≥75 years. Continuous variables were compared using t-tests or one-way analysis of variance (ANOVA), and categorical variables were compared using chi-square tests. Effects of age, diabetes duration, and haemoglobin A(1C) (HbA(1c)) on BC and BMD were assessed with multiple linear regression models. RESULTS: In T2D, in females, changes in fat mass index (FMI) were positively correlated with age, while changes in lean mass index (LMI) were unrelated to age. Changes in FMI or LMI in males were unrelated to age. For regional BC distribution, changes in visceral adipose tissue (VAT) were positively correlated with age for both males and females, while changes in appendage lean mass (ALM) were negatively correlated with age. For BMD, changes in total BMD (TBMD) in males were not correlated with age, while changes in lumbar spine BMD (LBMD) were positively correlated with age, and femoral neck BMD (FNBMD) was negatively correlated with age. Changes in BMD in all parts of females were negatively correlated with age. In addition, changes in BC and BMD were unrelated to diabetes duration, and HbA(1c) was mainly associated with decreases in lean mass but had little effect on other BC and BMD parameters. CONCLUSION: In T2D, changes in BC and BMD were associated with age but not diabetes duration. A higher HbA(1c) is associated with lower lean mass.