Does Glucose Control in Type 2 Diabetes Affect Cardiovascular Risk?

Findings from the ACCORD and ADVANCE studies (JW Cardiol Jun 6 2008) called into question the benefit of intensive glucose control for patients with type 2 diabetes. Results are now available from a third study, the open-label Veterans Affairs Diabetes Trial, which also compares an intensive glucose-lowering strategy with standard therapy in these patients.

The investigators enrolled 1791 veterans (mean age, 60.4; mean years since diabetes diagnosis, 11.5) with poorly controlled type 2 diabetes (mean HbA_1c level, 9.4%). Patients with body-mass indexes ≥27 initially received metformin plus rosiglitazone, and those with BMI <27 initially received glimepiride plus rosiglitazone. Participants randomized to intensive therapy were prescribed maximal doses, and those randomized to standard therapy were prescribed half the maximal doses. Insulin was added for patients who did not achieve HbA_1c levels <6% in the intensive-therapy group and <9% in the standard-therapy group. The primary outcome was time to first occurrence of a cardiovascular event.

The median HbA_1c stabilized by 6 months at 8.4% in the standard-therapy group and at 6.9% in the intensive-therapy group. At a median follow-up of 5.6 years, no significant benefit in the primary outcome was associated with intensive therapy (hazard ratio, 0.88; P=0.14). Ninety-five deaths occurred in the standard-therapy group, and 102 occurred in the intensive-therapy group (HR, 1.07; P=0.62). The two groups did not differ in the incidence of microvascular complications, including retinopathies, neuropathies, and nephropathies.