For nearly two decades, people with insulin-dependent diabetes have been using continuous glucose monitors (CGMs): Wearable sensors that detect glucose levels in the intracellular fluid just under the skin, transmit readings wirelessly to receivers or smartphones, and cue patients to take steps such as adjusting insulin or boosting their blood sugar levels. The CGM loop was closed in the fall of 2016, when the FDA approved the first hybrid closed-loop CGM system, Medtronic’s MiniMed670G, that collects and analyzes glucose data with sophisticated algorithms that determine both the timing and amount of insulin needed by the patient. When the system is placed in auto mode, data is used to trigger a small insulin pump for calculated delivery of insulin.
Closed-loop systems with wearable technology may be the key to offering real-time interventions for patients with burdensome conditions that require constant vigilance.
Brian Layden, M.D., Ph.D., associate professor of medicine at the University of Illinois at Chicago and an endocrinologist with the Jesse Brown Veterans Affairs Medical Center, said the closed-loop CGM is useful for people with Type 1 diabetes, the autoimmune form that often requires patients to inject insulin several times daily. “Type 1 diabetes is increasing, but not dramatically. It only represents about 5 percent of our diabetes cases now.” The vast majority of Layden’s patients, particularly older veterans, have the more lifestyle-dependent Type 2 diabetes, which is often treated with oral medications.
Casual observers may notice an important element missing from this loop: the physician. But when clinicians such as Ansari and Shaikh talk about closing the loop, they’re not talking about making themselves obsolete; they’re acknowledging the impossibility of monitoring and delivering health care around the clock. Layden spends plenty of time with patients – both those with Type 1 and Type 2 diabetes – and is intimately involved in their care. Said Huang: “We don’t want patients to feel as if, once they’re given a technology, they’ll rely on that and never meet with the doctor anymore or do therapy.”
Ansari foresees the next generation of wearable monitors, and even closed-loop systems, as complementary to physicians’ care. “My thought as a physician,” she said, “is that it will help improve patients’ relationships with their doctors.” Her migraine patients, for example, often have difficulty documenting symptoms in their prescribed headache diaries. “If there were a way to automatically sense that, or if we were able to find a way to have patients input data with the click of a button, all of the sudden that improves the doctor/patient relationship and makes it so much easier for us to give the advice they’re going to need to improve their migraines, or whatever else is going on.”
A graphic depicting an interpretation of the “Internet of Wearable Things.” Image courtesy of Dr. Ming-Chun Huang, EECS CWRU
When he looks to the future, Huang, the computer scientist, envisions an “Internet of Wearable Things” that not only assists in the care of individual patients, but also forms pools of data that can be studied and mined by research physicians – essentially combining the data collected by wearables with environmental context to improve clinical care in the same way map applications crunch constant streams of user data to recommend the best routes for other users.
Such an approach, he realizes, raises important questions about the security of patient data, particularly when it’s being processed by an artificial intelligence to perform big-picture analyses. “That makes it more complicated to protect the data itself,” he said. “Of course, some people say we should never share that data, but that contradicts our vision of the Internet of Wearable Things – that we can use that data from sensors to improve other people’s lives.”
When the next generation of wearables begins to affect patient care – and perhaps collect data that can be aggregated for big-picture analysis – this concern will become paramount, Ansari cautions. If doctors and researchers are collecting mountains of data about patients, there will need to be safeguards in place to keep patient-specific data out of the hands of third parties with other motivations, such as employers or insurers. “These are some questions we don’t necessarily have the answers to right now,” she said, “but I think we’re going to have to sort [them] out as time goes on.”
Still, she sees the next generation of wearables as inevitable – and welcome – tools for improving patient care, which is why she’s devoted so much time and effort to investigations at the VA’s Advanced Platform Technology Center. “As these technologies grow and we get even a better understanding of how we’re able to use them,” she said, “I think we’re going to be able to get a lot more holistic and well-rounded care provided to our patients.”