Continuous Glucose Monitoring Urged in Type 1 Diabetes

By Kristina Fiore, Staff Writer, MedPage Today

Published: October 14, 2011
Reviewed by Robert Jasmer, MD; Associate Clinical Professor of Medicine, University of California, San Francisco and Dorothy Caputo, MA, RN, BC-ADM, CDE, Nurse Planner

Both pediatric and adult patients with type 1 diabetes should use continuous glucose monitoring (CGM) to measure blood glucose levels, according to new guidelines.

There's high-quality evidence from studies showing that CGM can reduce the risk of hypoglycemia and help maintain good glycated hemoglobin (HbA1c) control in both populations, David Klonoff, MD, of Mills-Peninsula Health Services in San Mateo, Calif., and colleagues reported in a clinical practice guideline from the Endocrine Society. The guideline was published in the October issue of the Journal of Clinical Endocrinology and Metabolism.

"There are still concerns about the high costs of CGM and the accuracy of the various systems available," Klonoff said in a statement. "However, the new guideline shows that CGM can be a beneficial tool to help maintain target levels of glycemia and limit the risk of hypoglycemia."

Standard blood glucose monitoring with finger sticks can provide only intermittent snapshots of glucose levels, the researchers said, and often miss sustained hyperglycemic and hypoglycemic excursions.

On the other hand, CGM allows for more complete blood glucose profiles, though there have been concerns over the accuracy of interstitial tissue sampling compared with actual blood levels. However, newer devices have shown improved accuracy, Klonoff and colleagues reported.

In their review of the literature for creating the guidelines, they found sufficient high-quality evidence to recommend the use of real-time CGM in children and adolescents with type 1 diabetes who are at least 8 years old.

There was also high-quality evidence to recommend CGM in adult type 1 diabetes patients, they wrote.

The guidelines also suggested intermittent use of CGM in both children and adults who can't use real-time CGM, in order to analyze nocturnal hypoglycemia, the "dawn phenomenon," and postprandial hyperglycemia. Intermittent use also can help manage hypoglycemic unawareness, as well as assist patients when significant changes are made to their diabetes regimens.

They noted, however, that this suggestion was made on the basis of low-quality evidence.

The guidelines also recommend against the use of CGM in the intensive care unit or in the operating room "until further studies provide sufficient evidence for its accuracy and safety in those settings."