In Men With Obesity, T2DM Is Associated With Poor Trabecular Microarchitecture and Bone Strength and Low Bone Turnover

Abstract

Introduction: Obesity and type 2 Diabetes (T2D) are both associated with greater bone mineral density (BMD) but increased risk of fractures. The effect of the combination of both conditions on bone metabolism, microarchitecture, and strength in the obese population remains unknown.

Methods: Data from 112 obese men were collected. Bone turnover and biochemical markers were measured by enzyme-linked immunosorbent assay, body composition and BMD at all sites were assessed by dual energy X-ray absorptiometry, whereas bone microarchitecture and strength (stiffness and failure load) were measured by high-resolution peripheral computed tomography. Data were compared among metabolically healthy obese (MHO) and metabolically unhealthy obese (MUHO) with and without T2D and between obese without and with T2D.

Results: Compared to MHO and MUHO without T2D, MUHO with T2D had significantly lower levels of osteocalcin ((7.49 ± 3.0 and 6.03 ± 2.47 vs 4.24 ± 2.72 ng/mL, respectively, P = 0.003) and C-terminal telopeptide of type I collagen (CTx) (0.28 ± 0.10 and 0.29 ± 0.13 vs 0.21 ± 0.15 ng/mL, respectively, P = 0.02). Dividing our subjects simply into those with and without T2D showed that obese men with T2D had significantly lower levels of osteocalcin (P = 0.003) and CTx (P = 0.005), greater trabecular separation at the tibia and radius (P = 0.03 and P = 0.04, respectively), and lower tibial failure load and stiffness (both P = 0.04), relative to obese men without T2D.

Conclusion: In men, the combination of obesity and T2D is associated with reduced bone turnover and poorer trabecular bone microarchitecture and bone strength compared to those who are obese but without T2D, suggesting worse bone disease.

Trial registration: ClinicalTrials.gov NCT03490513.

Keywords: bone microarchitecture; diabetes mellitus; obesity; osteoporosis.

Published by Oxford University Press on behalf of the Endocrine Society 2021.

Figures

Figure 1.

Flow diagram of recruitment.

Figure 2.

Osteocalcin and C-terminal telopeptide of type 1 collagen (CTx) serum levels in metabolically healthy obese (MHO), metabolically unhealthy obese without T2D (MUHO no T2D) and MUHO with T2D (MUHO + T2D); error bars represent SD. post-hoc analysis for Osteocalcin showed P-value < 0.05 for the comparison between MUHO with T2D vs MHO$ and vs MUHO without T2D (A); post-hoc analysis for CTx showed P-value < 0.05 for the comparison between MUHO with T2D vs MUHO without T2D. $P < 0.05 for comparison of MUHO with T2D to MHO; #P < 0.05 for comparison of MUHO with T2D to MUHO without T2D (B). Comparison of osteocalcin levels between obese subjects without and with T2D showed a P-value 0.003 (C), and CTx levels between obese subjects without and with T2D showed P-value of 0.0005 (D).

Figure 3.

Tibial bone failure load (F.load) (A) and stiffness (B) in metabolically healthy obese (MHO), metabolically unhealthy obese without T2D (MUHO no T2D) and MUHO with T2D (MUHO + T2D); error bars represent SE. Values were adjusted for age (years), free testosterone (nmol), and free estradiol (pmol). P = 0.09 between groups. Considering progression in metabolic condition (3 groups) as linear, trend analyses show statistically significant decrease in F.load and stiffness (both P = 0.03). Tibial bone failure load (F.load) (C) and stiffness (D) in obese without T2D (Obese no T2D) and obese with T2D (Obese + T2D); error bars represent SE. Values are adjusted for age (years), free testosterone (nmol) and free estradiol (pmol).