Effect of acarbose on additional insulin therapy in type 2 diabetic patients with late failure of sulphonylurea therapy

Aim: The present study investigated the effect of acarbose on insulin requi rements and glycaemic control in patients with type 2 diabetes receiving ex ogenous insulin due to secondary failure of maximum dose sulphonylurea ther apy. Methods: A single-centre, double-blind, randomized, placebo-controlled stud y was performed in 48 type 2 diabetic patients with late-term failure follo wing at least 3 years of sulphonylurea therapy requiring additional insulin therapy to determine the impact of acarbose on glycaemic control and insul in requirements. The primary end points were glycaemic response rate (respo nders being predefined as patients who achieve a decrease in HbA(1c) to les s than 8% or a reduction by at least 15% as compared to the baseline values ) and the daily insulin dose at 6 months. Secondary parameters assessed inc luded postprandial changes in blood glucose, serum insulin and C-peptide du ring the treatment period. Results: There were significantly more responders in the acarbose-treated g roup compared with the placebo group (20/24 patients vs. 10/19 patients; p < 0.05). The mean daily insulin dose after 24 weeks of treatment was 16.4 /- 10.1 IU in the acarbose group and 22.4 +/- 12.2 IU in the placebo group (mean +/- s.d.; p < 0.07). Postprandial increases in blood glucose, insulin and C-peptide were consistently lower in the acarbose-treated group than i n the placebo group. For example, the mean increase in 2-h postprandial ser um insulin remained almost unchanged in the acarbose group at the end of 24 weeks of treatment compared to an increase to 43 +/- 29 mu U/ml (mean +/- s.d.) at the end of the study period for the placebo group. Conclusions: The findings of this study suggest that the addition of acarbo se to sulphonylurea/insulin combination therapy can improve glycaemic contr ol in type 2 diabetic patients. Acarbose may also reduce insulin resistance and hyperinsulinaemia.