Abstract: AIM: To prospectively study the effect of Metformin and life style education on plasma glucose and the progression of intima-media thickness (IMT)of the common carotid in patients with impaired glucose tolerance (IGT). METHODS: Patients with IGT were randomizely divided into two groups (group A and group B).Patients in group A were educated by healthy life style and patients in group B took Metformin 250 mg three times daily associated with healthy life style education for one year.One year later patients of two groups were measured carotid IMT and oral glucose tolerance test again. RESULTS: At study entry there was no significant difference of plasma glucose and carotid IMT between the two groups.One year later postprandial plasma glucose in group B was significantly lower than that in group A (7.9±1.2 mmol/L vs 8.7 ±1.4 mmol/L, P =0.002)and the increasement of IMT in group B was significantly lower than that in group A (0.001 ±0.010 mm vs 0.006 ±0.014 mm, P =0.042). CONCLUSION: Metformin reduces postprandial plasma glucose and delays the progression of IMT of common carotid.

Key words: impaired glucose tolerance, metformin, intima-media thickness, atherosclerosis