The Impact of Serum C-peptide Level on Bone Mineral Density in Postmenopausal Type 2 Diabetic Women.

Abstract

Objective: Recent studies suggested that c-peptide had biological activity on bone metabolism. We aimed to evaluate the impact of c-peptide level on bone mineral density (BMD) in postmenopausal type 2 diabetic women.
 Methods: Thirty-five insulin naïve type 2 diabetic postmenopausal women were included in our prospective cohort study. Fasting and random c-peptide, parathyroid hormone (PTH), vitamin D, insulin, alkaline phosphatase level (ALP) levels and BMD were evaluated.
 Results: The mean age of patients was 61.8±8.56 years. The mean fasting c-peptide, random c-peptide and insulin levels were 3.0±1.24, 7.7±3.7 and 13.9±11.2 µIU/ml, respectively. The mean femoral neck (FN-BMD) and total lumbar spine bone mineral density (L-BMD) were 0.787±0.127 and 0.919±0.122 g/cm2, respectively. C-peptide level was associated with total hip BMD (p<0.05) but this relation disappeared after regression analysis adjusted for confounders. A negative correlation between PTH level and FN-BMD was found (p=0.01). Total hip BMD and L-BMD were negatively correlated with age (p=0.01 and p=0.02, respectively). A positive association between DPP4 inhibitor treatment and total hip BMD was observed (p=0.03).
 Conclusions: We observed a positive association between total hip BMD and serum c-peptide level. However, this relationship disappeared in multiple linear regression analysis. Further studies are necessary to evaluate the impact of c-peptide level on the risk of osteoporosis in T2DM.