Are CGMs too expensive, and can the information overwhelm some?
The biggest obstacle to many people using CGM is cost. “The main downside of using a CGM without diabetes is cost, since insurance won’t usually cover a CGM if the patient does not have diabetes,” said Marilyn Tan, MD, FACE, chief of the Endocrine Clinic, Stanford Health Clinic, Palo Alto, Calif. “Even for patients with diabetes but not on insulin, CGM coverage can be challenging, as out-of-pocket costs for CGM are variable.”
The lifestyle companies mentioned above charge $139-$399 per month, which covers two CGM sensors, each one good for 14 days. Users need to subscribe to a plan for service and delivery. Additional services such as nutrition counseling may be available at an additional cost. Because CGMs in the United States require a prescription, these companies offer web screening and access to a web-based provider.
If healthy patients feel that the informational value of CGMs is worth the money, then they shouldn’t be discouraged, the experts believe.
“There’s little risk of harm with wearing a CGM,” Dr. Tan said, although she acknowledges that “[t]oo much information can also be overwhelming for some individuals.”
Users need to consult with their clinicians to ensure they understand the readings, Dr. Peters said. “You have to tell them not to overreact if the device reads low [glucose] or not to freak out if they get an alarm.” A high glucose reading, indicating hyperglycemia, can be caused by a steroid injection, or older people may experience a postprandial high after eating, she added. “They need to talk to their healthcare provider to interpret the data especially if they are out of [the ideal glucose] range.”
Dr. Klonoff agreed that there is a risk of people trying to “medicalize” too much information. “If you have a fever, you don’t have to go to a doctor to know you have an infection,” he said.
And the point, he added, is not to obsess over the individual numbers but to look for patterns particularly as predictors of metabolic syndrome. If a patient’s glucose is primarily in range, he or she wouldn’t necessarily worry about diabetes. But if it’s out of range more than 10% of the time, it might mean that patient is at risk for diabetes. “It might be time to counsel the patient to eat healthier and exercise more,” he said. “It’s never wrong to steer people to a healthier lifestyle.”
But another issue is whether the numbers from CGMs are entirely accurate in people without diabetes. A 2020 study published in the American Journal of Clinical Nutrition had 16 adults without diabetes wear both the Dexcom G4 Platinum CGM and Abbott FreeStyle Libre Pro for 28 days.
Researchers found that mean postprandial glucose was higher with the Dexcom than with the Abbott system, suggesting that “postprandial glycemic excursions were somewhat inconsistent between the CGMs.” The authors concluded that it may be too early to personalize meal recommendations via CGM.
Dr. Isaacs said perhaps the happy medium is for those without diabetes to just use CGMs occasionally. “It’s ... unclear [if] the right [use] of CGM needs to be continuous or if periodic use, such as once every 3 months, is enough for benefits,” she concluded.
A version of this article first appeared on Medscape.com.