The Relationships Between Glycated Hemoglobin and Bone Turnover Markers in Patients with Type 2 Diabetes but No Diabetic Nephropathy

Purpose: To investigate the relationships between glycated hemoglobin (HbA1c) level and bone turnover markers (BTMs) in patients with type 2 diabetes mellitus (T2DM) but no diabetic nephropathy. Patients and Methods: Patients with T2DM were recruited at Hebei General Hospital in China. The participants were allocated to three groups: an HbA1c <7% group, an HbA1c 7%-9% group, and an HbA1c >= 9% group. Their general characteristics, biochemical indices, and BTM concentrations were recorded. Results: The ages of the HbA1c <7% group and the HbA1c 7%-9% group were significantly higher than that of the HbA1c >= 9% group (P<0.05). The prevalence of a history of hypertension in the HbA1c 7%-9% group was significantly higher than that in the HbA1c >= 9% group. The circulating low-density lipoprotein-cholesterol concentration in the HbA1c >= 9% group and the apolipoprotein B concentration in the HbA1c 7%-9% group were significantly higher than those in the HbA1c <7% group (P<0.05). Compared with that in the HbA1c <7% group, the circulating 25-hydroxyvitamin D (250HD) concentration was significantly lower in the HbA1c >= 9% group (P<0.05). Additionally, the circulating 25OHD and osteocalcin (OC) concentrations negatively correlated with HbA1c (P<0.05). Conclusion: An increase in HbA1c is associated with gradual decreases in the circulating concentrations of 25OHD and OC.