Today, I want to talk to you about glucose monitoring. There are two ways to do this. The traditional way is to use a blood glucose monitor (BGM). People with diabetes prick their fingers and place the drop of blood onto a test strip. This can be done daily or multiple times per day. Because it involves a fingerstick, people usually don’t do it more than once or twice a day.
However, we are in the midst of a glucose monitoring revolution.
More and more people with diabetes are using continuous glucose monitors (or CGM). With the CGM devices, a small transmitter device plus sensor attaches to the skin. The person with diabetes gets continuous readings throughout the day by just looking at a reader or an app on their mobile phone. If the user looks at a glucose level every 5 minutes, then he or she will see 288 glucose readings per day without doing a single fingerstick. Such dense data allows people with diabetes to really see how food, exercise, and medications affect their glucose levels.
Most diabetes specialists like myself have always believed that giving a CGM to a person with type 1 diabetes or a person with type 2 diabetes who is using mealtime insulin would be very beneficial. In fact, clinical research studies have proven that. Recently, Dr. Thomas Martens and colleagues published the results of the MOBILE Study, where CGM was examined in people with type 2 diabetes not on meal-time insulin.* The study participants were treated with basal insulin. Those who used the Dexcom CGM device for 8 months had a lower A1C, lower average glucose, fewer high glucoses over 250 mg/dL and spent more time in the target range. In an extension study, patients whose CGM was taken away had worsening of their glucose levels.
This study shows that CGM can help people not by helping them dose their insulin better (the study participants were not on mealtime insulin) but rather by helping them adjust their food choices and exercise levels.
I think it is a matter of human nature. If you tell someone with diabetes that their glucose is high, that person might go for a walk or skip dessert or do something different to get the glucose down into range. With BGM, you don’t really know what your glucose level is all the time, so eating seconds of the pasta dish or having a piece of pie would not result in any negative feedback.
As CGM devices are getting smaller, more accurate, and less expensive, it makes a lot of sense that more and more people with diabetes will benefit from using them. Annoying fingersticks will eventually become a thing of the past.
*Martens, T, Beck RW, Bailey R, et al.; MOBILE Study Group. JAMA 2021;325:2262–2272