Continuous glucose monitoring has most often been used by people with Type 1 diabetes. That may change.
You’ve seen him sing, act, dance. This February you got a chance to hear him complain about fingersticks. In case you missed it, Nick Jonas appeared in a Super Bowl commercial to plug the Dexcom G6 continuous glucose monitor. Jonas was diagnosed with Type 1 diabetes when he was 13.
People with Type 1 diabetes (a condition in which the pancreas produces little or no insulin) are already familiar with continuous glucose monitoring (CGM). But as they watched Jonas on TV, how many millions of those with Type 2 diabetes were left wondering if they too could benefit from CGM?
The Super Bowl ad was just one boost for CGM in 2021:
- In April, a study funded by Abbott (which makes the FreeStyle Libre) and published in the Journal of the Endocrine Society showed that acquisition of its flash CGM system was associated with reductions in acute diabetes-related events and all-cause inpatient hospitalizations. (Flash CGM systems allow users to scan the sensor and view current glucose value and trends.)
- On July 15, Dexcom announced that the U.S. Food and Drug Administration cleared for marketing the Dexcom Partner Web application programming interfaces (APIs), allowing the company to enable third-party developers (e.g., Garmin, Livongo) to integrate CGM data into their digital health apps and devices.
- Three days later, on July 18, Medicare eliminated the requirement of the four-time-daily fingerstick in order to qualify for coverage of a continuous glucose monitor. The American Diabetes Association called the decision a “big win,” adding that the requirement “was an unnecessary barrier for Medicare beneficiaries.”
Instead of requiring users to prick their fingertips multiple times per day, CGMs use a tiny sensor wire inserted below the surface of the skin (usually on the abdomen or back of the arm) and secured with an adhesive patch. The sensor monitors the person’s glucose levels throughout the day and night. The readings are transmitted to a handheld electronic receiver (a “reader”) or smart device, where real-time data is provided to users about their glucose levels. The person can also review how their glucose changes over a few hours or days. Ideally, viewing glucose levels in real time can help people make more informed decisions throughout the day about how to balance food, physical activity and medicines.
Studies have shown the effectiveness of CGMs for people with Type 1 diabetes. In 2020, for example, the American Diabetes Association said that practical and quality-of-life-related benefits of CGM were “well documented.”
How about Type 2?
Statistics support growing interest in CGM for people with Type 2 diabetes. Of the 34 million Americans who have diabetes, only 5% to 10% have Type 1, according to the Centers for Disease Control and Prevention. The rest have Type 2.
Another 88 million have prediabetes, meaning their blood sugar levels are higher than normal, but not yet high enough to be diagnosed as Type 2 diabetes. Even people with prediabetes could potentially benefit from CGM by encouraging them to improve their lifestyles, according to researchers at UAB Medicine in Birmingham, Alabama.
Two years after Dexcom introduced its fully mobile G5 CGM in August 2015, the company published a study in the Annals of Internal Medicine demonstrating that CGM by adults who received multiple daily insulin injections for Type 2 diabetes led to improved glycemic control. This past June, the company published a study in JAMA Network showing that in a randomized clinical trial including 175 adults with Type 2 diabetes, there was a significantly greater decrease in HbA1c levels over eight months with continuous glucose monitoring than with blood glucose meter monitoring (–1.1% vs –0.6%).
Not everyone is convinced of the efficacy of CGM for those with Type 2 diabetes.
“Most people with type 2 diabetes do not require self-monitoring of blood glucose, and unnecessary monitoring not only wastes money but can negatively impact quality of life,” wrote Allen F. Shaughnessy, PharmD, MMedEd, Tufts University School of Medicine, in the June 2020 issue of American Family Physician. “Until we have research supporting continuous glucose monitoring for patients with Type 2 diabetes, especially those not receiving regular insulin injections, there are no patient-oriented benefits to justify its great expense and additional hassles for patients and physicians.”
But recent developments show the market is moving in a different direction.
In March 2021, researchers from Oregon Health and Science University in Portland, Oregon, reported that randomized controlled trials in intensively insulin-treated T2D demonstrated the efficacy and safety of real-time CGM (rtCGM) in reducing glycated hemoglobin without increasing hypoglycemia.
At the American Diabetes Association 81st Scientific Sessions in June 2021, Newton, Massachusetts-based Onduo shared data from its virtual care program for people with Type 2 diabetes demonstrating significant and sustained improvement in HbA1c.
The Onduo health management program combines a mobile app with remote lifestyle coaching and telemedicine visits with specialists. Individuals with Type 2 diabetes have access to endocrinologists, monitoring, and prescriptions for Dexcom G6 continuous glucose monitoring devices for intermittent use in high-risk participants.
“Participants who have an A1c >8% when they join Onduo, or are on insulin or a sulfonylurea, or haven’t seen their primary care provider in a year, or have had a recent emergency room visit, are offered CGM for intermittent use,” said Onduo Senior Director of Medical Affairs in an email to Repertoire. “Onduo will continue to follow clinical guidelines and best practices for use of CGM. We also will continue to conduct research on the use of CGM in type 2 diabetes, as we are uniquely positioned to advance knowledge in this field.”
The CMS decision
Meanwhile, the recent CMS decision to offer coverage for a continuous glucose monitor even without the four-time-daily-fingerstick requirement could be significant for people with Type 2 diabetes who use multiple daily injections of insulin, said Laura Young, M.D., PhD, associate professor of medicine at UNC School of Medicine in Chapel Hill, North Carolina, in an email to Repertoire.
“When patients do not achieve adequate glycemic control with non-insulin therapies, basal insulin is generally initiated. In this situation, patients will typically check their blood glucose values 1-2 times per day. If after initiation of basal insulin, glycemic targets are still not met, intensification to multiple daily injections [is warranted]. It is estimated that 24% to 54% of patients with type 2 diabetes fall into this category. In this situation testing blood glucose values at least four times per day is required to help patients and caregivers adequately dose insulin and avoid hypoglycemia.”
Meanwhile, the development of newer, non-insulin agents, and a resulting decrease in the number of patients requiring basil bolus therapy, could affect the impact of the CMS change, she said.
Diabetes by the numbers
- 34.2 million U.S. adults have diabetes, and one in five of them don’t know they have it.
- Approximately 5-10% of those 34 million people have Type 1 diabetes. The remainder have Type 2.
- Diabetes is the seventh leading cause of death in the United States.
- Diabetes is the No. 1 cause of kidney failure, lower-limb amputations
and adult blindness.
- In the last 20 years, the number of adults diagnosed with diabetes has more than doubled.