Association of Bone Metabolism Markers with Glycemic Parameters in Type 2 Diabetes Mellitus: Insights from a Cross-sectional Study on Serum Osteocalcin, Vitamin D, and Parathyroid Hormone

Background: Bone is increasingly recognized as an endocrine organ that influences glucose metabolism, particularly through markers such as osteocalcin (OC), vitamin D3, and parathyroid hormone (PTH).The aim of this study was to assess the association between these bone metabolism markers and glycemic control in patients with type 2 diabetes mellitus (T2DM), providing insight into their potential impact.Materials and methods: A cross-sectional analytical study was conducted in 200 individuals -100 with T2DM and 100 healthy controls.Blood samples were analyzed for fasting blood sugar (FBS), postprandial blood sugar (PPBS), glycated hemoglobin (HbA1c), total cholesterol (TC), triglycerides (TG), low-density lipoprotein (LDL), serum creatinine, urea, serum OC, 25(OH)D3, and PTH.Statistical analyses included t-tests, Pearson correlation, and Chi-square tests to assess differences and associations between groups.Results: Patients with type 2 diabetes had significantly lower levels of OC (p < 0.001) and vitamin D3 (p < 0.001) and higher levels of PTH (p < 0.001) compared to the control group.Glycated hemoglobin levels were inversely correlated with vitamin D3 (r = -0.430,p < 0.01) and OC (r = -0.296,p < 0.05) and positively correlated with PTH (r = 0.565, p < 0.001).A significant association was also observed between vitamin D deficiency and elevated PTH levels in patients with diabetes (p < 0.001).Serum creatinine levels were significantly higher in the diabetic group (p < 0.001), whereas urea levels did not show a significant difference.Lipid parameters were variably associated with glycemic indexes across groups. Conclusion:This study reveals significant abnormalities in bone metabolism markers in patients with T2DM, with poor glycemic control associated with decreased OC and vitamin D3 levels and elevated PTH levels.These findings highlight the potential clinical importance of bone biomarkers in assessing metabolic risk and guiding therapeutic strategies in patients with T2DM.