The preventive effect of Acarbose and Metformin on the IGT population from becoming diabetes mellitus: a 3-year multicentral prospective study

Objective To assess the effect of pharmacological and non pharmacological interventions on Chinese subjects with impaired glucose tolerance (IGT). Methods In this 3 year prospective study, 321 subjects aged above 25 years with IGT were included. IGT was defined by 1985 WHO criteria utilizing a 75 g oral glucose tolerance test (OGTT). The subjects were divided into control (C), diet plus exercise (D+E), Acarbose (Glucobay, A) and Metformin (M) groups. The subjects in the group D+E underwent an individually designed diet and exercise program, the importance of which was reiterated annually. The group C only received conventional education on diabetes prevention. The two pharmacological groups were orally given Acarbose (50 mg, t.i.d) and Metformin (0.25 g, t.i.d) respectively. OGTT, weight, height, blood pressure, lipids were measured yearly during the follow up. The t test, Chi square test and proportional hazard regression analysis were used to analyze the risk reduction in diabetes conversion from each group. Results The baseline data of 4 groups had no statistical differences. By the end of study, both the fasting plasma glucose (FPG) and the 2h postprandial plasma glucose (2hPG) in group C elevated (FPG from 6.02 mmol/L to 6.59 mmol/L, 2hPG from 8.83 mmol/L to 9.13 mmol/L), and the annual diabetes incidence was 11.6%. The corresponding changes in group D+E were FPG from 6.11 mmol/L to 6.21 mmol/L, PG2h from 9.28 mmol/L to 8.98 mmol/L, and 8.2% of annual diabetes incidence. In contrast, both the FPGandthe2hPG significantly decreased in group A (FPG from 6.03 mmol/L to 5.47 mmol/L, 2hPG from 8.34 mmol/L to 7.21 mmol/L)andingroup M (FPG from 6.01 mmol/L to 5.85 mmol/L, 2hPG from 9.05 mmol/L to 7.92 mmol/L). Theannualdiabetesincidencedecreasedto2.0% in group A, and 4.1% in group M. Proportional hazard regression analysis showd that the annual diabetes incidence was positively correlated with the baseline 2hPG and body mass index (OR=1.33, P=0.006 and OR=1.11, P=0.008, respectively), and negatively correlated with group C and group M (OR=0.12, P=0.0001 and OR=0.23, P=0.0002, respectively). Conclusion Thenaturaldiabetesincidenceis 11.6% in IGT population, and 8.2% in population with conventional diet and exercise interventions, between them there is no significant difference. The pharmacological interventions with Acarbose or Metformin significantly decrease diabetes incidence of IGT population.