Boosting Insulin May Prolong Lives Post-Heart Attack

Diabetes patients who have a heart attack improve survival odds with intensive insulin

(RxWiki News) People with diabetes who have had a heart attack face an even greater likelihood of having a second one. Keeping glucose levels under control through insulin therapy may reduce this risk.

When blood sugar levels are high, fatty deposits are more likely to build up in blood vessel walls and block blood flow. This narrowing of arteries (atherosclerosis) increases mortality risk.

Swedish scientists have recently discovered that patients with type 2 diabetes who have had a heart attack survived an average of two to three years longer if they received concentrated insulin treatment early on rather than the standard therapy to lower blood sugar.

"Control blood sugar levels to reduce heart attack risk."

Viveca Ritsinger, MD, with the Unit of Cardiology of the Department of Medicine, Karolinska Institute, Stockholm, Sweden and colleagues followed 620 diabetes patients who participated in the Diabetes Mellitus Insulin Glucose Infusion in Acute Myocardial Infarction (DIGAMI 1) trial, which began in 1990.

Of the subjects who were admitted to the hospital for suspected heart attack, 306 were randomly selected to receive intensive insulin treatment. This therapy involved an insulin-glucose infusion for at least 24 hours, followed by insulin injections four times a day for at least three months.

The goal of the insulin-glucose infusion was to stabilize a patient’s blood glucose between 7.0 and 10.9 mmol/L. Patients originally had blood glucose concentrations of more than 11 mmol/L.

The other 314 patients served as the control group and were given standard treatment for one year. They received insulin rarely — only if considered necessary by an attending physician.

Over the course of 20 years of follow-up, most patients died, but those in the intensive treatment group tended to live longer. The median survival time for the intensive-therapy patients was 7.0 years compared to 4.7 years for those receiving the standard treatment. Scientists said the intensive-insulin patients lived an average of two to three years longer.

The authors noted that the survival difference between the two groups may not be as great today because standard treatment has improved over the decades to include medications that lower cholesterol and blood pressure.

In an accompanying commentary, Denise Bonds, MD, of the National Institutes of Health, Bethesda, Maryland, emphasized that the study still demonstrates the benefit of good glucose control.

“In 20 years, we have gone from few glucose-lowering therapies to over half a dozen oral therapy drugs, plus insulin, plus effective treatments to reduce the risk of elevated lipids and blood pressure,” she wrote. “Now, the challenge is choosing the best treatment option for our patients.”

The study was published in May in The Lancet Diabetes & Endocrinology. Funding was provided by the Swedish Heart-Lung Foundation and the Kronoberg County Council.

Review Date: 
May 17, 2014