Circulating Levels of Sclerostin Are Increased in Patients with Type 2 Diabetes Mellitus

Abstract

Diabetes mellitus is a risk factor for osteoporotic fractures. Sclerostin is an inhibitor of bone formation. However, there are no data about sclerostin levels in type 2 diabetes mellitus (T2DM). The aims were to evaluate serum sclerostin in T2DM patients and to analyze its relationship with bone metabolism. This was a cross-sectional study. We compared serum sclerostin in the T2DM group (n = 74) and control group (n = 50), and we analyzed its relationship with calciotropic hormones, bone turnover markers, bone mineral density (BMD), and morphometric vertebral fractures. Sclerostin levels were significantly higher in T2DM patients than control subjects (P < 0.001) and in T2DM males than in T2DM females (P < 0.001). Serum sclerostin was positively correlated with age in males T2DM (P = 0.031). In linear regression analysis, gender, study group, and age were predictive of sclerostin levels (P < 0.05). Sclerostin concentrations were positively associated with duration of T2DM (P = 0.064) and glycated hemoglobin (P = 0.074) independently of age in T2DM patients. Sclerostin was inversely related to bone turnover markers (P < 0.05) and positively related to lumbar spine, femoral neck, and total hip BMD (P < 0.05) in the T2DM group. Sclerostin was significantly lower in osteoporotic than nonosteoporotic patients with T2DM (P = 0.048). Circulating sclerostin is increased in T2DM independently of gender and age. Serum sclerostin is also correlated with duration of T2DM, glycated hemoglobin, bone turnover markers, and BMD in T2DM patients. Additional studies are needed to evaluate the role of sclerostin on bone metabolism in this population.