Compared with male patients with type 2 diabetes mellitus (T2DM), those with type 1 diabetes mellitus (T1DM) or latent autoimmune diabetes in adults (LADA) have lower bone mineral densities (BMDs), according to study results published in the Journal of Endocrinological Investigation.
While metabolic alterations in patients with diabetes may adversely affect bone mass, limited data exist on the association between specific diabetes types and osteoporosis. The objective of the current study was to compare BMDs among male patients with LADA, classical T1DM, and T2DM, and to identify risk factors for developing low BMD.
In the cross-sectional study, the researchers included 57 patients (mean age, 58.1 years; duration of diabetes, 9.7 years) with LADA, 67 patients (mean age, 44.7 years; duration of diabetes, 11.7 years) with classical T1DM, and 223 patients (mean age, 56.9 years; duration of diabetes, 9.4 years) with T2DM, all of whom received treatment at the endocrinology department of Shanghai Tenth People’s Hospital between January 2017 and October 2020. Dual-energy x-ray absorptiometry was used to assess BMD at the lumbar spine, femoral neck, and right hip.
Compared with patients with T2DM, among those with LADA, BMDs, T-scores, and Z-scores at the lumbar spine (0.89 g/cm3, -1.63, and -0.96, respectively), femoral neck (0.75 g/cm3, -1.38, and -0.50, respectively), and right hip (0.82 g/cm3, -1.26, and -0.81, respectively) were significantly low; however, the BMDs, T-scores, and Z-scores in the LADA group were comparable to the classical T1DM group. Osteoporosis was more common in patients with LADA and classical T1DM compared with patients with T2DM.
Multiple linear regression analysis of the association between BMD and clinical indicators in all patients with diabetes showed that body mass index (BMI), uric acid, and fasting C-peptide were significantly positively associated with BMD at all 3 skeletal sites.
In patients with T2DM, there was a positive association between BMI and BMD at all sites; fasting C-peptide and uric acid were positively associated with BMD at the femoral neck and right hip; age was negatively associated with BMD at the femoral neck and right hip; and osteocalcin was negatively associated with BMD only at the femoral neck. In patients with LADA, osteocalcin was negatively associated with BMD at the lumbar spine and femoral neck.
The study had several limitations, including the single center and cross-sectional design, relatively small sample size, the exclusion of women, and potential selection bias.
“Compared with male patients with T2DM, lower BMDs were observed in patients with LADA and T1DM. Low BMI, uric acid, C-peptide levels, and high osteocalcin levels are risk factors for developing low BMD in male patients with diabetes,” the researchers concluded.
Zhang M, Sheng C, You H, et al. Comparing the bone mineral density among male patients with latent autoimmune diabetes and classical type 1 and type 2 diabetes, and exploring risk factors for osteoporosis. J Endocrinol Invest. Published online January 2, 2021. doi:10.1007/s40618-020-01472-6