“Studies have found that people with type 1 diabetes who use CGMs [continuous glucose monitors] are able to maintain better control of their blood sugar without increasing episodes of hypoglycemia when blood sugar drops to dangerous levels, compared to those who self-monitor blood glucose with periodic finger sticks,” the chair of the guideline task force, Anne Peters, MD, a professor of medicine at the University of Southern California, Los Angeles, said in a Sept. 26 statement.
The group recommended CGMs for well-controlled type 1 patients as well as those above hemoglobin A1c (HbA1c) targets, so long as they want and understand how to use the devices. It also suggested short-term, intermittent CGM use to help type 2 patients meet HbA1cgoals. Insulin pumps were recommended over multiple daily injections for type 1 patients above target HbA1clevels, as well as those who meet their target but continue to have severe hypoglycemia or high glucose variability. For patients with type 2 disease, pumps were suggested for cases of poor glycemic control despite intensive insulin therapy, oral agents, and other measures.
The Endocrine Society and others have been pushing Medicare to cover CGMs for a while; the new guideline seems to support the effort. Although the devices are used by type 1 patients and covered by some insurance plans, they are only indicated as finger-stick adjuncts, not replacements. For Medicare coverage, they would “need to serve a primary medical purpose and not be used adjunctively,” according to a recent review by Dexcom, a company seeking a primary monitoring indication for its CGM.
The Endocrine Society noted in its evidence-based guideline that standard capillary blood glucose measurements “offer only a limited perspective on the constant daily changes in blood glucose levels,” and, unlike continuous monitoring, “do not provide alarms that indicate when blood glucose levels are above or below various thresholds, and do not indicate trends in blood glucose levels.”
The society commissioned a pooled analysis of 11 randomized trials that showed a 0.3% reduction in HbA1c with real-time glucose monitoring, mostly in patients 15 years or older. Other studies cited by the group also showed better HbA1c control than with finger sticks, without an increased risk of hypoglycemia.
The guideline also suggested insulin pumps for type 1 patients who want greater flexibility and convenience and that insulin pump therapy should continue during hospitalizations. It also suggested encouraging patients to use the embedded bolus calculators in their pumps so long as they “have appropriate education regarding their use and limitations.”
The Endocrine Society funded the work, with cosponsorship from the American Association for Clinical Chemistry, the American Association of Diabetes Educators, and the European Society of Endocrinology. Several of the authors have industry ties to companies that make CGMs or insulin pumps. Dr. Peters is an advisor for Abbott, Becton Dickinson, AstraZeneca, Biodel, Medtronic, and other companies, as well as a speaker, investigator, and advisor for Janssen.