Does Treatment of Impaired Glucose Tolerance Improve Cardiovascular Outcomes in Patients with Previous Myocardial Infarction?

PURPOSE: We evaluated the effects of an alpha-glucosidase inhibitor, voglibose, on cardiovascular events in patients with a previous myocardial infarction (MI) and impaired glucose tolerance (IGT).

METHODS: This prospective, randomized, open, blinded-endpoint study was conducted in 112 hospitals and clinics in Japan in 3000 subjects with both previous MI and IGT receiving voglibose (0.6 mg/day, n = 424) or no drugs (n = 435) for 2 years. The Data and Safety Monitoring Board (DSMB) recommended discontinuation of the study in June 2012 after an interim analysis when the outcomes of 859 subjects were obtained. The primary endpoint was cardiovascular events including cardiovascular death, nonfatal MI, nonfatal unstable angina, nonfatal stroke, and percutaneous coronary intervention/coronary artery bypass graft. Secondary endpoints included individual components of the primary endpoint in addition to all-cause mortality and hospitalization due to heart failure.

RESULTS: The age, ratio of males, and HbA1 C were 65 vs. 65 years, 86 vs. 87%, and 5.6 vs. 5.5% in the groups with and without voglibose, respectively. Voglibose improved IGT; however, Kaplan-Meier analysis showed no significant between-group difference with respect to cardiovascular events [12.5% with voglibose vs. 10.1% without voglibose for the primary endpoint (95% confidence interval, 0.82-1.86)]; there were no significant differences in secondary endpoints.

CONCLUSION: Although voglibose effectively treated IGT, no additional benefits for cardiovascular events in patients with previous MI and IGT were observed. Voglibose may not be a contributing therapy to the secondary prevention in patients with MI and IGT.

TRIAL REGISTRATION: Clinicaltrials.gov number: NCT00212017.