Issue: November 2019
November 21, 2019
3 min read

Is CGM use appropriate for people with non-insulin-dependent type 2 diabetes?

Issue: November 2019
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Click here to read the Cover Story, "As diabetes technologies advance, matching patients to the ‘right’ device challenges providers."


CGM should be used in every diabetes education program for newly diagnosed patients.

I tend to agree with most of my colleagues and say the way glucose monitoring is currently used, it has no value in this population. The data have no value unless they are perceived as actionable information that is reviewed by someone who knows what to do with the numbers. That is the issue.

It is true that most people with type 2 diabetes, especially if they are on medications that are not putting them in danger — meaning putting them at risk for hypoglycemia — will not need to have glucose numbers flashing all the time. However, CGM offers an opportunity for the person with diabetes to “check in” with themselves and, ideally, with a health care provider, to look at a variety of things. Am I on the right medication, and is it working? Do I have an opportunity to learn what I need to know to manage my diabetes effectively?

William H. Polonsky

There are two ways you can use CGM and flash data for the person with type 2 diabetes. One is in the moment, which is potentially very valuable. The other is reviewing retrospective data, which we greatly underuse even in type 1 diabetes. That is understandable, because people do not want to sit down and look at their retrospective data for the same reason someone won’t sit down and balance their checkbook. What I see is tremendous opportunity for using episodic CGM in all diabetes populations to help people get on track and stay on track with their disease. This is something that could be done once every quarter. Think of it as a “How am I doing?” visit.

Why would you give a patient another boring lecture on carbohydrates or the importance of exercise when you could give them a CGM and say, “Let’s hang out here, eat and see what happens.” This is discovery learning and passing along useful knowledge that is meaningful for people. We could do this tomorrow. This is an incredible opportunity that patients and providers should utilize.

William H. Polonsky, PhD, CDE, is president of the Behavioral Diabetes Institute and an associate professor at the University of California, San Diego. Disclosure: Polonsky reports he has served as a consultant for AstraZeneca, Dexcom, Eli Lilly, Intarcia, MannKind, Merck, Novo Nordisk and Sanofi.



A complex and time-consuming therapy will not overcome patient and physician inertia.

Most clinicians agree that CGM use among people with type 2 diabetes using insulin, at least for the multiple daily injection population, can be helpful. The use of CGM among people with type 2 diabetes prescribed oral diabetes therapy is much more controversial, as there is less data around this topic.

Big picture, diabetes is a disease of managing glucose values. If you have more data, the patient and the provider can see that data in real time. As CGM becomes more cost-effective, we will use it for those patients on basal insulin, people who are newly diagnosed and even in prediabetes. There is real-time value for the person using CGM when they get to see how certain foods, drinking alcohol or going for a walk affect them. Once they see it, it really starts to hit home.

Jeremy H. Pettus

That said, available data are a lot less impressive with respect to changes in HbA1c following CGM use in this population. If you have an individual with type 2 diabetes on metformin monotherapy and their HbA1c is 6.5%, what else is CGM data going to do other than provide education? That tipping point will change as costs come down. For right now, CGM is not practical. Our patients prescribed oral agents might not need that information.

For now, clinicians should focus on getting patients to adhere to current regimens. The emphasis should be placed on adding therapy at an appropriate, and ideally early, time. These therapies must be easy to prescribe, easy to obtain and easy to take, and have a large and recognizable benefit.

Currently, CGM does not fit these criteria for people with type 2 diabetes not taking insulin.

CGM will one day become the standard of care for type 2 diabetes, especially as the technology becomes easier to use and cost comes down. With the proper support, CGM could become a powerful motivational tool. However, we need innovative training materials and new methods for providing CGM feedback.

Episodic use may be useful for some patients, but much more evidence is needed to determine who will derive the most benefit.

Jeremy H. Pettus, MD, is assistant clinical professor of medicine in the School of Health Sciences at the University of California, San Diego. Disclosure: Pettus reports he has served on advisory boards for Insulet, MannKind, Novo Nordisk, Sanofi, Tandem and Valeritas, and has received speaking fees from Sanofi and Valeritas.