Effect of different treatment on pancreatic β-cell function and insulin resistance after initial intensive insulin therapy in newly diagnosed type 2 diabetes

Abstract

Objective To explore the effects of different treatment on pancreatic β-cell function and insulin resistance after initial intensive insulin therapy in newly diagnosed type 2 diabetes. Methods One hundred and twenty five newly diagnosed type 2 diabetes patients were enrolled as the subjects from January 2014 to December 2014 in Department of Endocrinology, the People's Hospital of Qingyuan city. These patients were administered with 14 days of continuous subcutaneous insulin infusion with metformin. After the blood sugar reached the standard levels(fasting blood glucose:4.4-6.1 mmol/L and 2 h postprandial blood glucose<8 mmol/L), these patients were randomized divided into the three subsequent treatment groups for 3 months follow-up treatment through the random number table: group A (44 patients): basal insulin analogues; group B(39 patients): premixed insulin analogues; group C(42 patients): sulfonylureas insulin secretagogue. The body mass index(BMI), fasting plasma glucose (FPG), glycosylated hemoglobin(HbA1c), lipids were measured in each group before and after treatment, and the different time's blood C-peptide levels were measured during intravenous glucose tolerance test. Acute insulin response (AIR), C-peptide area under curve, homeostasis model assessment for β cell function (HOMA-β), homeostasis model assessment-insulin resistance(HOMA-IR) were calculated. The least significant difference t-test and one-way ANONA were used to analyze the quantitative variables between groups. Correlation analysis was used test the relationship among variables. Results The HOMA-β significant improved（9.7±1.4 vs 2.3±1.2, 10.0 ± 1.7 vs 2.7 ± 1.3, 7.3 ± 1.8 vs 2.3 ± 1.4，F=28.620，all P<0.01), HOMA-IR(0.28 ± 0.16 vs 0.48 ± 0.33, 0.28±0.13 vs 0.40 ± 0.23, 0.24±0.12 vs 0.39±0.23，F=39.162，all P<0.01) was decreased in each group. HOMA-β in group A and group B were significantly different from that in Group C (9.7 ± 1.4 vs 7.3 ± 1.8, t=-3.23, 10.0±1.7 vs 7.3 ± 1.8, t=2.53, all P<0.01). Conclusion After initial intensive insulin treatment in newly diagnosed type 2 diabetes patients, the efficacy in the insulin intensive therapy groups is significant better in improving the β-cell function. Key words: Diabetes mellitus, type 2; Initial intensive therapy; Subsequent therapy; βcell function; Insulin resistance