Moderate Glucose Target May Reduce Deaths : Moderate blood glucose control was linked to a significant 40% reduced mortality after CABG.

Major Finding: After receiving a coronary artery bypass graft, patients who maintained a moderate blood glucose level of 126–179 mg/dL had a significant 40% lower mortality and a significant 30% lower rate of major complications, compared with patients whose mean blood glucose was 180 mg/dL or higher. Mortality and morbidity were not significantly lower in patients who maintained a blood glucose level of less than 126 mg/dL, compared with patients with levels that were 180 mg/dL or higher.

Data Source: Review of more than 4,600 post-CABG patients at a single U.S. center during 1995–2008.

Disclosures: Dr. Ailawadi said that he and his associates had no disclosures. Dr. Lazar disclosed that he has received research support from Eli Lilly & Co.

TORONTO — Moderate glucose control during the first days following coronary artery bypass graft surgery led to better outcomes than did liberal control, judging by a review of more than 4,000 patients at one U.S. center.

Patients who were maintained on tight glucose control, however, with an average blood glucose level of less than 126 mg/dL during the first 3 days after undergoing CABG, had no significant outcome advantage over those who were maintained on liberal control at a mean glucose level of more than 180 mg/dL.

On the basis of these findings as well as those of previous published studies, the ideal blood glucose target after CABG is 150 mg/dL, with a target range of 120–150 mg/dL, Dr. Gorav Ailawadi said.

Moderate glucose control, defined by Dr. Ailawadi as a mean blood glucose level during the first 3 days after surgery of 126–179 mg/dL, was linked to a significant reduction in both mortality and major complications, compared with liberal control, said Dr. Ailawadi, who is a cardiothoracic surgeon at the University of Virginia in Charlottesville.

“At our institution, our postoperative glucose control policy as of January 2010 has been a target range of 120–150 mg/dL hospitalwide,” not just in cardiac surgery patients, he said in an interview.

“The previous goal had been 80–110 mg/dL, but we felt there were enough data, including our own data, to support the change. We're not saying that you can be lax about glucose, but that you don't need to be as tight as 80–110 mg/dL. The goal is 120–150 mg/dL, and be sure it doesn't go above 180 mg/dL.”

Although it's unclear why tight control may not be as effective as moderate control, Dr. Ailawadi suggested that perhaps patients in the tight-control group have more hypoglycemic episodes.

In this series, the incidence of first postoperative glucose levels that measured 60 mg/dL or less ran 1.5% in the tight-control patients, 0.4% in the moderate-control group, and 0.1% in the liberal-control group, a significant difference for the tight-control patients compared with the other two groups.

Dr. Ailawadi said that the evidence in favor of moderate control confirms results from several recent randomized, controlled studies, including:

The Normoglycemia in Intensive Care Evaluation—Survival Using Glucose Algorithm Regulation (NICE-SUGAR) study, which included 6,100 intensive care unit patients and found that a glucose target of less than 180 mg/dL led to significantly better survival than did a target of 81–108 mg/dL (N. Engl. J. Med. 2009;360:1283–97).

A study that randomized 400 on-pump cardiac surgery patients to tight postoperative glucose control with a target of 80–100 mg/dL or to conventional treatment with a blood glucose goal of less than 200 mg/dL and an achieved mean level of 157 mg/dL.

At 30 days' follow-up, the incidence of the primary end point—a composite of death, sternal infections, prolonged ventilation, cardiac arrhythmias, stroke, and renal failure—was identical in the two groups.

But the group on tight control had a trend toward more deaths that neared significance (P = .061) and a significantly higher rate of stroke (Ann. Intern. Med. 2007;146:233–43).

An unpublished study that randomized cardiac surgery patients to tight postoperative glucose control with a target mean level of 90–120 mg/dL, compared with a target mean of 120–180 mg/dL, and showed no significant difference in the rates of major adverse cardiovascular events between the two groups.

Dr. Harold L. Lazar, professor of cardiothoracic surgery at Boston University and lead investigator of that study, summarized the results during the discussion of Dr. Ailawadi's report.

Dr. Lazar also noted that the 2009 report from the Blood Glucose Guideline Task Force of the Society of Thoracic Surgeons set an “optimal glucose range” of 120–180 mg/dL for the peroid during and after adult cardiac surgery (Ann. Thorac. Surg. 2009;87:663–9).

A reason the task force selected this range was “to make it easier for people to be in compliance,” he said.