Objective: To investigate the effects of early intensive therapy on beta cell function and long-term glycemic control in newly diagnosed type 2 diabetic patients with different recruiting fasting plasma glucose (FPG) levels.
Methods: A total of 382 newly diagnosed type 2 diabetic patients with FPG 7.0 - 16.7 mmol/L were randomly assigned to therapy with insulin in the form of continuous subcutaneous insulin infusion (CSII) or multiple daily injection (MDI) or oral hypoglycemic agents (OHA, by using gliclazide and/or metformin) for initial rapid correction of hyperglycemia. The treatments were stopped after euglycemia had been maintained for 2 weeks. The patients were followed longitudinally on diet alone for 1 year. Intravenous glucose tolerances tests (IVGTTs) were performed and blood glucose, insulin and proinsulin were measured before and after therapy as well as at 1-year follow-up. Homeostasis model assessment (HOMA) of beta cell function and insulin resistance index (HOMA-beta and HOMA-IR) were calculated. All the patients were stratified on the recruiting FPG: stratum A (7.0 mmol/L </= FPG < 11.1 mmol/L), stratum B (11.1 mmol/L </= FPG </= 16.7 mmol/L).
Results: More patients in stratum A achieved target glycemic control (94.4% vs 89.8%) and in shorter time [(5.9 +/- 3.8) d vs (6.9 +/- 3.6) d, P < 0.05] as compared with those in stratum B. beta cell function represented by HOMA-beta and acute insulin response (AIR) improved significantly after intensive interventions in both stratum A and B patients. However, the remission rate at 1 year was significantly higher in stratum A patients (47.8%) than those in stratum B (35.7%, P < 0.05). The patients treated with insulin (especially with CSII) had higher remission rates and better improvement of AIR at 1 year follow-up irrespective of the recruiting FPG (CSII or MDI vs OHA: 57.1%, 51.8% vs 32.8% in stratum A, P < 0.05; 44.4%, 38.7% vs 18.6% in stratum B, P < 0.05).
Conclusions: Compared with OHA, early short time intensive insulin treatment had more favorable outcomes on maintaining AIR and prolonged glycemic remission in newly diagnosed type 2 diabetic patients irrespective of the recruiting FPG levels.