A study of the effects of acarbose on glucose metabolism in patients predisposed to developing diabetes: the Dutch acarbose intervention study in persons with impaired glucose tolerance (DAISI)

Background We hypothesized that acarbose would delay conversion from impaired glucose tolerance (IGT) to type 2 diabetes by alleviating postprandial hyperglycaemia. Our study's main objective was to investigate the effect of acarbose in IGT‐persons on their 2‐h plasma glucose level and beta‐cell function. Subjects and Methods The study included a random sample of 45–70‐year‐old residents of Hoorn, Netherlands, with mean fasting plasma glucose < 7.8 mmol/L and mean 2‐h plasma glucose of 8.6–11.1 mmol/L (measured by two successive oral glucose tolerance tests). After a qualification period, participants were randomized to acarbose treatment or placebo. Insulin secretion and insulin sensitivity were measured by hyperglycaemic clamp. After a 3‐year treatment, analyses were performed of both the intention‐to‐treat and the per‐protocol groups. Results Of the 12 093 residents who received postal invitations, 118 participants were randomized. The mean difference of the post‐load plasma glucose after 3 years, was − 1.16 mmol/L (95% CI: − 2.03; − 0.17). The absolute risk reduction for diabetes was 6% (95% CI: − 9; 21). No effect was seen on insulin secretion and insulin sensitivity. Conclusions In patients with IGT, treatment with acarbose was associated with beneficial effects on 2‐h plasma glucose levels but not with improvement of beta‐cell function.