Context：  The worldwide explosive increase in type 2 diabetes mellitus and its cardiovascular morbidity are becoming major health concerns.

Objective： To evaluate the effect of decreasing postprandial hyperglycemia with acarbose,an a-glucosidase inhibitor,on the risk of cardiovascular disease and hypertension in patients with impaired glucose tolerance(IGT).

Design,Setting,and Participants： International,multicenter double-blind,placebo-controlled,randomized trial,undertaken in hospitals in Canada,Germany,Austria,Norway,Denmark,Sween,Finland,Israel,an Spain from July 1998 through August 2001.A total of 1429 patients with IGT were randomized with 61 patients(4%) excluded because they did not have IGT or had no postrandomization data,leaving 1368 patients for a modified intent-to-treat analysis.Both men(49%) and women(51%) participated with a mean (SD) age of 54.5(7.9) years and body mass index of 30.9(4.2).These patients were followed up for a mean (SD) of 3.3(1.2) years.

Intervention： Patients with IGT were randomized to receive either placebo(n=715) or 100 mg of acarbose 3 times a day(n=714).

Main Outcome： Measure The deelopment of major cardiovascular events(coronary heart disease,cardiovascular death,congestive heart failure,cerebrovascular event,and peripheral vascular disease) and hypertension(>140/90 mmHg).

Results： Three hundred forty-one patients (24%) discontinued their participation prematurely,211 in the acarbose-treated group and 130 in the placebo group;these patients were also followed up for outcome parameters.Decreasing postprandial hyperglycemia with acarbose was associated with a 49% relative risk reduction in the development of cardiovascular events(hazard ratio [HR],0.51;95% confidence interval[CI];0.28-0.95;P=0.03) and a 2.5% absolute risk reduction. Among cardiovascular events, the major reduction was in the risk of myocardial infarction(HR,0.09;95%CI,0.01-0.72;P=0.02).Acarbose was also associated with a 34% relative risk reduction in the incidence of new cases of hypertension(HR,0.66;95%CI,0.49-0.89;P=0.006) and a 5.3% absolute risk reduction.Even after adjusting for major risk factors,the reduction in the risk of cardiovascular events(HR,0.47;95%CI,0.24-0.90;P=0.02) and hypertension (HR,0.62;95%CI,0.45-0.86;P=0.004) associated with acarbose treatment was still statistically significant.

Conclusion： This study suggests that treating IGT patients with acarbose is associated with a significant reduction in the risk of cardiovascular disease and hypertension.