The Future of Continuous Glucose Monitoring Technology

In a recent diaTribe interview with David Panzirer and Dana Ball, two of the main figures behind the Helmsley Charitable Trust’s Type 1 Diabetes program, both men were asked what would be the most important advance in type 1 diabetes over the next five or ten years. Both men answered that improved continuous glucose monitoring technology has the potential to revolutionize the lives of people with type 1 diabetes.  David Panzirer:  “I think the most important advance in the next five years will be a CGM that will be accurate enough to begin to automate some insulin delivery. I have always said if we can automate basal rates overnight and keep people in control, that this would have a dramatic impact on those living with type 1 diabetes.” Dana Ball: “In the next five years, incredibly accurate, easy to wear, connected sensors. I believe the future of personalized care for patients with diabetes is in sensor use and adoption.”

I read their comment with particular attention, both because our eight-year-old daughter, Bisi, just started on the Dexcom G4 Platinum in April and because I had just been to an event in Boston put on by the Glu network (an online community that’s part of the T1D Exchange) where two people from Dexcom talked about the future of their product; a panel of people affected by type 1 diabetes talked about constant glucose monitoring and other topics related to the condition; and people in the audience shared their thoughts on CGMs, diabetes management, and the importance of finding a community. Below, I’ve picked out some of the highlights of the event.

David Rogers, the Dexcom territory business manager, started by giving a quick history of his company and glucose sensor technology. CGMs are based on engineering work done in the 1960s that developed the idea of using an enzyme electrode as a biometric sensor. Dexcom was founded in 1999, and has released several models over the years, each becoming more and more accurate. The latest is the Dexcom G4 Platinum, released for adults in 2012 and for children as young as two earlier this year. The mean accuracy of the G4 is now within 13% of hospital-calibrated glucose meters. (They did not talk about the accuracy of the pediatric sensor. I was told by Dexcom when Bisi started on the sensor to follow the 20/20 Rule: Above 80, I could expect the sensor number to be within a 20% range of the blood glucose numbers we get from Bisi’s meter—so anywhere from 20% above to 20% below. Below 80, I could expect the sensor number to be within 20 points, above or below, of the number on Bisi’s meter.  From our limited experience, admittedly short and anecdotal, the pediatric monitor does not seem quite as accurate as the adult one is purported to be.) The company is planning a software upgrade to the G4’s algorithm that will bring the accuracy to within 10%, and the ultimate goal of the company is to replace fingersticks with CGM technology. For the next generation G5, the company is working on improved accuracy, a simpler applicator, longer sensor life, and reduced calibration (the G4 must be calibrated with glucose numbers from finger sticks at least twice a day).

Of course, the holy grail of diabetes technology right now is an accurate sensor integrated with a pump (in Europe, Dexcom has already been integrated into the Animas Vibe). Here in the U.S., Dexcom has deals with several pump companies at various stages of development. The Dexcom-Animas match is under review at the FDA; a Dexcom integrated into a Tandem t:slim pump is at an earlier stage of development. And the company has just reopened talks with Omnipod—a fact I was particularly glad to learn, since Bisi is a very happy Omnipod user. (Omnipod and Dexcom broke off an agreement about three years ago. As Dexcom’s CEO describes it, “We were engaged, we broke off the engagement, but now we are talking again.”)

Separate from these agreements, there are now 23 different artificial pancreas projects going on just in the U.S. Dexcom is working with 19 of those.

Dexcom also has another product under review at the FDA, called Share: a cradle with Bluetooth capabilities that will share your glucose number and high or low alarms via smartphone with up to five people you choose (note that this will only work when the transmitter is sitting in the cradle, so perhaps would be more useful for nighttime numbers than daytime, when a person and their transmitter are usually on the move). Eventually, said Laura Endres, Dexcom’s national sales director, the company hopes to be able to skip the cradle and have numbers go directly from the Dexcom transmitter to an iPhone. I could imagine that this could be very useful when Bisi is older and more independent. Even when she’s out and about, I could see her numbers pop up on my phone. Endres pointed out that it could give an extra layer of safety to adults too, say if someone’s on a business trip and their transmitter alerts their spouse back home of a low during the night. Future sensors, she predicted, would bypass the transmitter and communicate directly with smart phones, or with something as small and convenient as a watch.

Both the Dexcom representatives and people in the audience talked about the barriers to adoption of the G4: the cost of the technology, and the fact that some insurance programs—including Medicare—don’t cover it. One older woman in the audience pointed out that while her CGM and the expensive sensors that go with it are covered now, as soon as she switches to Medicare, they won’t be. Endres said that Dexcom is working very hard to get CGMs covered under all insurance plans (which would help bump up the number of users), but that type 1 diabetes patients should also try to push their representatives in Congress for better coverage of medical technology.

Once Endres and Rogers finished their presentation, the attention switched to the panelists: Kerri Sparling of the blog Six Until Me, Scott Scolnick, a territory manager for the Tandem pump company (who was diagnosed 37 years ago), Megan Gable, who is the parent of a child with type 1 diabetes, and Anna Floreen, who was diagnosed at six and works for Glu. Their answers to the first question—“would you give up your pump before your CGM”—hinted at how much people come to rely and depend on the data provided by their CGMs.

Scolnick: “Yes, in a heartbeat, and I work for a pump company. I’m sorry, I’ll tell anybody. A pump is just a way to deliver insulin. What it’s really all about is your blood sugar.”

Sparling said she relied equally on both devices but admitted: “After seeing my numbers in context, I couldn’t go back. I feel unsafe when I’m separated from my Dexcom—it’s my safety net.” She also described how essential the CGM was during pregnancy, when your body is prone to “sneaky” lows, and, now that she’s a parent, to warn her of impending lows when she’s taking care of her child.

Scolnick commented that the CGM provides a tool to help discover and correct the mistakes that any diabetic inevitably makes when making constant decisions, day after day, week after week, and year after year. “What’s got me hooked is that feedback we get. When we make mistakes, and we all do, it catches you.  You catch those errors sooner and you can take action quicker.”

Floreen said that putting the numbers from her finger sticks in context has been incredibly valuable, and has helped shape her decisions about how she manages her diabetes. “For me just knowing this information of where I’d been—a certain meal didn’t show up as a road bump but as a Mt.  Washington! Having that information taught me to make better decisions.

She pointed out that even though many people in the room, including the panelists, viewed their CGMs as absolutely essential for managing their disease, fewer than 50% of type 1 patients use a CGM or are on a pump. “We need more so they develop the next generation. We need more people involved, we need people to talk about diabetes.” An audience member shared the same thought: “We are a bunch of diabetic nerds getting together. A lot of people don’t ask these questions or take advantage of these technologies. How do we get more people involved?”

The importance of patients being their own best and most knowledgeable advocates was a common theme. People pointed out that most endocrinologists specialize in type 2 diabetes, not type 1, and may not even know about advances like the newest CGM or the latest pump. An audience member commented: “This is a disease where the individual is managing it minute to minute. It is such a unique situation; doctors telling you what to do doesn’t necessarily work in this case.” Bill Woods, who works for Glu and the T1D Exchange, said that one of his goals at the T1D Exchange was to get all the non-profits to work together, to use their united strength to get advances pushed through more quickly. He also encouraged patients to become as knowledgeable as possible about the advances in treatment coming down the pike. “If Dexcom has a financial call for investors, listen to it so you can know what they’re working on. All this information is public.”

People also talked about the importance of connecting with others with type 1 diabetes—through message boards like on Glu, through events like this one, even through reaching out to someone else who’s wearing a pump or a CGM. One audience member said that this was the biggest group of type 1s he’d ever been in a room with. Woods said something that for me, as the parent of someone with type 1 diabetes, really struck a chord, and made think more about how isolating this disease must feel at times for Bisi. He described how when he goes to his doctor and gets an A1C number that’s higher than he’d like, his family members without diabetes are sympathetic, but there’s no way that they really understand what it feels like. “The networking around here is so impactful. All the other times I have a bubble around me, but all of you here have type 1 diabetes. This is who I really am. You all get it.”

With Bisi just starting out on the Dexcom CGM, it was great timing to hear a little bit more about how it works and what its future is. Even more important for me, though, was hearing the essential difference that CGMs are making in the lives of many of the people with type 1 at this event. We may be just at the beginning of the revolution that Panzirer and Ball of the Helmsley Trust describe, but it’s already clear that reliable continuous glucose monitoring technology is making a lot of people’s lives better than they were before.

Katie Bacon

Katie Bacon is a writer and editor based in Boston. Her daughter, Bisi, was diagnosed with type 1 diabetes in August, 2012, when she was six. Katie worked as an editor at The Atlantic, and her writing has appeared in The New York Times, The Boston Globe, and other publications. Katie and her husband, Mark, have two children—Bisi and her older brother, Jamie.

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Katie Bacon

Katie Bacon is a writer and editor based in Boston. Her daughter, Bisi, was diagnosed with type 1 diabetes in August, 2012, when she was six. Katie worked as an editor at The Atlantic, and her writing has appeared in The New York Times, The Boston Globe, and other publications. Katie and her husband, Mark, have two children—Bisi and her older brother, Jamie.