Current iterations of continuous glucose monitoring (CGM) evolved from enzyme-based electrochemical glucose sensors developed in the 1960s at Cincinnati Children’s Hospital in Ohio, USA. Glucose oxidase (GOx) placed on a platinum electrode catalyzed the oxidation of glucose to gluconolactone in the presence of oxygen, producing hydrogen peroxide and water as by-products. In the 1980s, oxygen was replaced with a synthetic redox electron acceptor, improving the accuracy of secondgeneration biosensors. Proprietary technical improvements resulted in an array of GOx CGM systems obtaining regulatory approval for routine use.
Despite considerable initial reluctance from many leading diabetologists to include CGM in diabetes management, clinical evidence has accumulated from research encompassing adult and pediatric populations with diabetes (1,2), hypoglycemia (3), use with sensor-augmented pumps (4,5), stand-alone use with multiple daily injections (6), outcomes during pregnancy (7), utility in type 1 and type 2 diabetes (8,9), and effects in real-life clinical settings (10). The article on p. 3 of this compendium offers a detailed discussion of published randomized clinical trials to date.
A recently introduced factory-calibrated intermittently scanned interstitial glucose monitoring system, also known as flash CGM (FCGM), is also based on GOx CGM technology and represents a new option with clinical benefit comparable to real-time CGM (11). FCGM received regulatory approval as a substitute for blood glucose testing and could conceivably replace traditional self-monitoring of blood glucose in diabetes management for people with diabetes who test multiple times per day (Figure 1).
The maturation of CGM technology and research is not only facilitating imminent development of closed-loop insulin delivery (12), but also substantiating the collection and analysis of continuous data as a routine treatment modality in major clinical guidelines (13,14). CGMderived metrics such as time in range and coefficient of variation are now regarded as viable parameters for everyday diabetes management, as well as for clinical research (15).
As newer CGM systems with patient-centered features (see the article on p. 8 of this compendium) become a clinical reality for individuals with type 1 or type 2 diabetes, appropriate educational and technical support for both people with diabetes and health care providers will be needed to solidify the emerging status of continuous glucose data as a standard of care for daily diabetes management.
The opinions expressed are those of the authors and do not necessarily reflect those of Abbott Diabetes Care or the American Diabetes Association. The content was developed by the authors and does not represent the policy or position of the American Diabetes Association, any of its boards or committees, or any of its journals or their editors or editorial boards.
Article Information
Dualities of Interest
I.B.H. has served as a consultant to Abbott Diabetes Care, Adocia, Bigfoot, and Roche. His institution has received research grant support from Medtronic.
T.B. has served on advisory boards of Bayer Health Care, Boehringer Ingelheim, DreaMed Diabetes, Eli Lilly, Medtronic, Novo Nordisk, and Sanofi. His institution has received research grant support, with receipt of travel and accommodation expenses in some cases, from Abbott Diabetes Care, Diamyd, GluSense, Medtronic, Novo Nordisk, Sandoz, and Sanofi. He has received honoraria for participating on the speakers bureaus of Bayer Health Care, Eli Lilly, Medtronic, Novo Nordisk, Roche, and Sanofi. He owns stock in DreaMed Diabetes.
A.L.P. has served on advisory boards for Abbott Diabetes Care, Becton Dickinson, Bigfoot, Boehringer Ingelheim, Eli Lilly, Lexicon, Livongo, Medscape, Merck, Novo Nordisk, OptumHealth, Sanofi, and Science 37. She has received research grant support from Dexcom and Mannkind. She participates on a speakers bureau for Novo Nordisk.J.J.C. participates in speakers bureaus for Janssen, Merck, Novo Nordisk, and Sanofi.
G.A. has served as a consultant and on a steering committee for Dexcom and on an advisory board for Novo Nordisk, and her institution has received research grant support from AstraZeneca and Novo Nordisk.
R.M.B.’s institution has received payment for his services as a research investigator, consultant, or advisory board member for Abbott Diabetes Care, Becton Dickinson, Boehringer Ingelheim, Bristol-Myers Squibb/AstraZeneca, Dexcom, Eli Lilly, Hygieia, Johnson & Johnson, Medtronic, Merck, Novo Nordisk, Roche, Sanofi, and Takeda. R.M.B. has inherited Merck stock, volunteers for the American Diabetes Association and JDRF, and receives funding from the National Institutes of Health for diabetes technology research.
Acknowledgments
Writing support services for this compendium were provided by Carol Verderese of The Diabetes Education Group in Lakeville, CT. Editorial and project management services were provided by Debbie Kendall of Kendall Editorial in Richmond, VA.
Author Contributions
All authors researched and wrote their respective section(s). Lead author I.B.H. reviewed all content and is the guarantor of this work.
REFERENCES
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