A new study in CMAJ indicates that intensive insulin therapy considerably increases the risk of hypoglycemia in critically ill patients. http://www.cmaj.ca/press/cmaj.090206.pdf

Numerous intensive care units worldwide use rigorous insulin therapy to control blood sugar. A range of organizations, such as the American Diabetes Association and the American Association of Clinical Endocrinologists, recommend it as a standard care for critically ill patients.

In 2001, a randomized trial found that intensive insulin therapy considerably reduced hospital mortality. However, later trials have reported conflicting results on mortality and higher rates of severe hypoglycemia.

Information from twenty six trials is taken into account in the CMAJ study. It includes the NICE-SUGAR Study on intensive insulin therapy which is an international, multicentre randomized trial, and is the leading intensive insulin therapy trial to date. The New England Journal of Medicine issues online the NICE -SUGAR study on March 24, 2009 and publishes it in the print edition on March 26, 2009.

Dr. Donald Griesdale, anesthesiologist and critical care physician, Vancouver General Hospital and clinical instructor, University of British Columbia and his team write: “By including the largest trial on intensive insulin therapy published to date, we provide the most current and precise estimate of the effect of intensive insulin therapy on vital status and hypoglycemia in the ICU setting.”

The twenty six trials analyzed in the CMAJ study included 13,567 patients. Results showed that the risk of hypoglycemia increased six times more than the control treatment.

The study was carried out by researchers from the University of British Columbia and Vancouver General Hospital, Vancouver, BC; Harvard School of Public Health, Brigham and Women’s Hospital, Beth Israel Deaconess Medical Center, Boston, Mass; Queen’s University and Kingston General Hospital, Kingston, Ontario; McMaster University, Hamilton, Ontario; Royal North Shore Hospital and the University of Sydney, Australia.

The researchers write, “We suggest that policy makers reconsider recommendations promoting the use of intensive insulin therapy in all critically ill patients.” However, as the study incorporated data from trials in diverse populations with a wide range of illness severity, they “cannot exclude the possibility that some patients may benefit from intensive insulin therapy and be at less risk of hypoglycemic events.”

Dr. Greet Van Den Berghe and his team note in a related observation that the variations in how the therapy was given explain the different results of each separate study. One single guideline for intensive insulin therapy suitable for all patients is not a valid proposal.

Written by Stephanie Brunner (B.A.)