Fewer Long-Term Cardiovascular Events with Intensive Glycemic Control

Ten years later, patients with type 2 diabetes assigned to intensive glucose-lowering therapy have fewer major adverse cardiovascular events but no reduction in cardiovascular mortality, according to a study in the New England Journal of Medicine.

The study reports extended follow-up data on patients enrolled in the Veterans Affairs Diabetes Trial. In that study of 1791 veterans with type 2 diabetes, intensive glucose-lowering therapy did not reduce the rate of major cardiovascular events at a median 5.6 years’ follow-up. For the primary outcome of major cardiovascular events, follow-up (median, 9.8 years) was available for 703 patients assigned to intensive therapy and 688 assigned to standard therapy. For the secondary outcomes of cardiovascular and all-cause mortality, the analysis included 837 and 818 patients, respectively (median, 11.8 years).

The median glycated hemoglobin levels during the trial were 6.9 percent in the intensive therapy group and 8.4 percent in the standard therapy group. Three years after the study ended, the difference was only 0.2 to 0.3 percentage points. At long-term follow-up, the risk of major cardiovascular events was significantly lower in the intensive therapy group: hazard ratio 0.83, with an absolute risk reduction of 8.6 events per 1000 person-years.

Neither cardiovascular nor overall mortality was significantly different between groups. The effects of intensive glucose control were similar for patients at higher versus lower cardiovascular risk.

Intensive glucose control may reduce the long-term risk of major cardiovascular events in older patients with long-standing type 2 diabetes, the results suggest. However, there is no reduction in the risk of death, overall or from cardiovascular causes. The potential benefits of intensive glycemic control should be weighed against the burdens and side effects of the specific treatment being considered, the researchers conclude [Hayward RA, et al. Follow-up of glycemic control and cardiovascular outcomes in type 2 diabetes. N Engl J Med 2015; 372:2197–2206].