Bone material strength in normoglycemic and hyperglycemic black and white older adults.

Abstract

This cross-sectional study assessed cortical bone properties via impact microindentation in adults with normoglycemia, prediabetes, and early-stage T2D. Bone material strength index was stable across the glycemia categories in whites but it declined in blacks. Blacks may be more susceptible than whites to impaired cortical bone properties in early diabetes. Individuals with long-standing type 2 diabetes (T2D) have altered cortical bone material properties as determined by impact microindentation. This cross-sectional study was done to determine whether altered cortical bone material properties could be detected in adults with prediabetes or early-stage T2D. Men and postmenopausal women aged ≥ 50 years with no diabetes (50 white, 6 black), prediabetes (75 white, 13 black), and T2D of ≤ 5 years duration (24 white and 16 black) had assessments of bone material strength index (BMSi) by impact microindentation, trabecular bone score (TBS), and bone mineral density (BMD) by DXA and the advanced glycation end product, urine pentosidine. The association between glycemia category and BMSi differed by race (interaction p = 0.037). In the whites, BMSi did not differ across the glycemia categories, after adjustment for age, sex, and BMI (no diabetes 76.3 ± 1.6 (SEM), prediabetes 77.2 ± 1.3, T2D 76.2 ± 2.5, ANCOVA p = 0.887). In contrast, in the blacks, BMSi differed (ANCOVA p = 0.020) and was significantly lower in subjects with T2D than in those with prediabetes (p < 0.05) and no diabetes (p < 0.05) (mean ± SEM BMSi in no diabetes 86.0 ± 4.3, prediabetes 91.0 ± 3.2, and T2D 71.6 ± 2.9). Neither TBS nor urine pentosidine differed significantly across the glycemia categories in either whites or blacks. These findings suggest different associations of glycemia with cortical bone material properties in blacks and whites, with blacks possibly being more susceptible to impaired cortical bone properties than whites in early diabetes. A larger study is needed to verify these observations.