Autore: Yan Yang, Xuejun Zhang, Mingjing Bao, Limei Liu, Yang Xian, Jichuan Wu, Pengqiu Li
Rivista: J Diabetes Investig Vol. 7 No. 2 March 2016
Aims/Introduction: To evaluate serum 25-hydroxyvitamin D3 (25(OH)D3) in newly diagnosed type 2 diabetes patients and to explore the associations of 25(OH)D3 with insulin resistance and b-cell function. Materials and Methods: A total of 97 newly diagnosed type 2 diabetes patients and 69 healthy controls were recruited. Serum 25(OH)D3 was determined using high-pressure liquid chromatography. Insulin resistance was measured using a homeostasis model assessment of insulin resistance (HOMA-IR). b-Cell function was determined using the HOMA b-cell function index (HOMA-b), early-phase insulin secretion index (DI30/DG30) and area under the insulin curve (AUCins). Correlation analysis was carried out using Pearson’s correlation and multiple stepwise regression analysis. Results: Serum 25(OH)D3 was much lower in patients with newly diagnosed type 2 diabetes(t = -13.00, P < 0.01), and the prevalence of hypovitaminosis 25(OH)D3 was 62.9% (61/97) in diabetic patients. Among the diabetic patients, patients with hypovitaminosis 25 (OH)D3 showed higher glycosylated hemoglobin and AUCglu (P < 0.01) as well as lower HOMA-b, DI30/DG30 and AUCins. Serum 25(OH)D3 was independently positively correlated with DI30/DG30 and AUCins (P < 0.05), but was not significantly correlated with either HOMA-IR or HOMA-b. Only triglycerides, glycosylated hemoglobin and DI30/DG30 emerged as independent factors associated with serum 25(OH)D3 in both diabetes patients and the health control group. Conclusions: The present results further showed a low serum 25(OH)D3 concentration in patients with newly diagnosed type 2 diabetes. 25(OH)D3 deficiency is associated with disturbances in glucose metabolism and lipid metabolism. Serum 25(OH)D3 is not correlated with basal insulin resistance or b-cell function, but is significantly positively correlated with glucose-stimulated insulin secretion and b cell function.
Effect of serum 25-hydroxyvitamin D3 on insulin resistance and b-cell function in newly diagnosed type 2 diabetes patients