Long-term Glycemic Control After 6 Months of Basal Insulin Therapy

Objectives To compare the effects of a 6-month course of insulin therapy versus oral antidiabetic drugs (OADs) on long-term (5-year) glycemic control in patients newly diagnosed with type 2 diabetes mellitus (T2DM) with severe hyperglycemia. Study Design 5 years' follow-up of a randomized controlled trial. Methods Newly diagnosed patients with T2DM and severe hyperglycemia were hospitalized and treated with intensive insulin injections for 10 to 14 days. Fifty patients were randomized to receive either insulin injections or OADs for an additional 6 months. Subjects were followed for 5 years to evaluate long-term glycemic control. We compared the glycated hemoglobin (A1C) levels of the treatment groups and the proportion of patients in each group who reached the treatment targets. We also examined the remission rate (A1C <= 6.5% without antidiabetic medication) at the end of the 5 years. The mechanisms of improved glycemic control and possible mechanism of remission were also investigated. Results At 5 years, A1C levels remained lower in the insulin group than in the OAD group (6.49 +/- 0.72% vs 7.72 +/- 06%; P = .012). The proportion of subjects with A1C levels <= 6.5% was significantly higher in the insulin group than in the OAD group (63.6% vs 23.5%; P = .013). The remission rate was 27.3% in the insulin group and 5.9% in the OAD group (P = .048). Conclusions This randomized trial demonstrated that a 6-month course of insulin therapy led to better 5-year glycemic control, reflected by lower A1C levels, than did oral antidiabetic agent therapy. Moreover, the insulin-treated group had a significantly higher rate of remission from diabetes.