Continuous Glucose Monitoring for Diabetes Management

Introduction to Continuous Glucose Monitors

The American College of Physicians recommends the Dexcom G6/G7 real-time continuous glucose monitoring system for most people with diabetes requiring glucose monitoring, particularly for those on insulin therapy, due to its FDA approval for treatment decisions without confirmatory blood glucose checks and its integration capabilities with automated insulin delivery systems 1, 2, 3

Real-time CGM (rtCGM) continuously measures and displays glucose levels with alarms for hypo/hyperglycemia, as recommended by the American Diabetes Association 4, 5
Intermittently scanned CGM (isCGM) measures glucose continuously but requires scanning for visualization, and is suitable for patients who do not require real-time alerts 4, 5

The FDA has approved the Dexcom G5/G6 systems for making treatment decisions without confirmatory blood glucose monitoring checks, as stated by the American College of Cardiology 1, 2, 3
The Dexcom G6, Dexcom G7, FreeStyle Libre 2 Plus, and Eversense E3 are FDA-approved for use with automated insulin delivery systems, according to the Endocrine Society 4

Real-time CGM in conjunction with intensive insulin regimens lowers HbA1c levels in adults with type 1 diabetes, with a Grade A recommendation from the American Diabetes Association 1, 2, 3
Real-time CGM is particularly beneficial for those with hypoglycemia unawareness or frequent hypoglycemic episodes, with a Grade B recommendation from the American College of Physicians 1, 2, 3
Daily use of real-time CGM provides maximal benefit, with a Grade A recommendation from the American Academy of Clinical Endocrinologists 1, 2, 3

The Dexcom G6/G7 has advantages including real-time glucose readings, FDA approval for treatment decisions, and compatibility with automated insulin delivery systems, as recommended by the American College of Endocrinology 1, 2, 3, 4
The FreeStyle Libre systems have advantages including lower cost and newer versions with alarms, but may have limitations such as requiring scanning for glucose readings and potential interference with certain medications, as noted by the European Association for the Study of Diabetes 1, 2, 3, 6
The Senseonics Eversense has advantages including implanted device providing real-time CGM for 5-6 months and FDA approval for use with AID systems, but requires minor surgical procedure for implantation, as stated by the International Diabetes Federation 6, 7

Certain medications and conditions can affect CGM accuracy, including high doses of acetaminophen, salicylic acid, and ascorbic acid, as well as acute physiological disturbances, according to the American Association of Clinical Endocrinologists 6, 7
Skin reactions due to irritation or allergy should be assessed and addressed, as recommended by the American Academy of Dermatology 5
Real-time CGM should be used daily for maximum benefit, and intermittently scanned CGM devices should be scanned at minimum once every 8 hours to avoid data gaps, as stated by the American Diabetes Association 1, 2, 3, 5

Patients with type 1 diabetes on insulin should use the Dexcom G6/G7 for real-time alerts and integration with insulin pumps, as recommended by the American College of Endocrinology 1, 2, 3
Patients with type 2 diabetes on multiple daily insulin injections should use either real-time CGM or intermittently scanned CGM based on need for alerts, as stated by the American Association of Clinical Endocrinologists 4, 5
Patients with type 2 diabetes on non-insulin therapy should consider intermittently scanned CGM for cost-effectiveness, as recommended by the American College of Physicians 4, 5
Patients with hypoglycemia unawareness should use real-time CGM with alerts, as strongly recommended by the American Diabetes Association 1, 2, 3