Continuous Glucose Monitoring: Forever Changing Diabetes Management
Friday, August 14, 2020
Today, patients with diabetes have a plethora of options when it comes to the treatment of their diabetes. Thanks to the internet and now smartphones, they have instant access to information. There are thousands of websites and apps which can help the patient better manage their diabetes. Yet even with all this advanced technology and newer and better drugs, that one glaring statistic remains a constant reminder that we have yet to crack the toughest nut of all: getting the majority of patients with diabetes under good control.
In this series we will first review CGM, explaining what it is, provide an overview of the current FDA approved systems, and explain how transformative this technology can be. We’ll examine how to incorporate CGM into your practice and look to the future and how this one piece of technology will forever change, for the better, the relationship between the patient with diabetes and their physician.
Before we jump into the deep end of the CGM, first, a brief history of glucose monitoring—a technology which, when first introduced back in the late 60s and early 70s, was complex to use while providing uneven results. It took 10 years or so before glucose meters became more patient friendly while providing more accurate results. At the time, these meters introduced several notable advancements, notably faster test results (5 seconds for some systems), even greater accuracy, alternate site testing, and connectivity so that data could be shared.
However, with each corresponding improvement in this technology, one indisputable fact remained: the majority of patients with diabetes were not monitoring their glucose as frequently as they should, or worse, not monitoring at all. Pundits attributed this to the fact that glucose monitoring was “painful” as the patient had to prick their finger to gather a blood sample. While we would never contend that finger pricks were an enjoyable experience, “pain” was not the real reason patients did not monitor their glucose regularly.
The real reason was that patients did not value the information provided, plus there was no action step executed based on these results. It should surprise no one that insulin pump patients were the most frequent testers, monitoring their glucose on average eight times per day, multiple daily injection (MDI) patients were next at four times per day, and so on. Insulin-using patients not only valued this information, but needed it so they could properly dose their insulin.
Yet even with frequent testers, these point to point systems had another major limitation: they provided an incomplete picture of what was really going on. Simply put, when it comes to diabetes management, some data is better than no data, but more data is better . (And yes, we will cover how CGM systems have evolved to combine all this data with analytics.) HbA1c is widely considered the gold standard for measuring control; however, this gold standard also provides an incomplete picture of the patient.
Simply put, CGM fills in the blanks while providing a more comprehensive overview of the patient. This is the true value of CGM for both the patient and the physician as it allows a three-dimensional look. Think of it this way: CGM allows the patient and physician to see what’s really going on. It can be seen whether the therapy regimen is working. It can be seen what happens after meals. It can be seen what happens while the patient is sleeping or exercising. CGM provides bright light where only darkness or limited light existed before.
CGM also has the additional benefit in that it’s more patient friendly, making glucose monitoring simple. Currently there are two systems which do not require any calibrations with a conventional glucose monitor. So, the days of a patient pricking their finger are gone forever; the “pain” factor has been eliminated. All four of the currently FDA-approved systems come with connectivity therefore eliminating the need to log readings. It also allows a patient to easily share this data with their physician. Even better, CGM sensor life has improved over the years, with sensors being worn for 10 or more days.
One of the hidden benefits of CGM is it eliminates the need for the patient to carry around any testing supplies. No lancets, no test strips, nothing. This may seem like a small benefit until you talk with a patient using CGM. When it comes to diabetes management the patient has enough to worry about already and the less “stuff” they have to have with them, the better.
In summary, CGM not only provides a better, clearer picture of what’s happening, it’s also more patient friendly. This is why we believe that in the not so distant future, CGM will replace conventional glucose monitoring as the standard for glucose measurement. CGM systems are widely reimbursed improving patient access to this technology. The data provided by CGM is extraordinarily accurate, so much so that insulin-using patients can now dose their insulin based on data provided by their CGM without also using a conventional monitor.
Sensor insertion has become quick and relatively pain-free. And thanks to connectivity, all the heavy lifting of the analytics is also done for the patient. As we know, data by itself is just a set of meaningless numbers, but data combined with analytics leads to knowledge. Armed with this knowledge, the patient and physician can take action, action which hopefully will lead to the ultimate goal of better outcomes.
Yet what really makes CGM the most transformative technology ever invented for patients with diabetes is that it helps ALL patients no matter how they manage their diabetes. This is perhaps one the most misunderstood aspects of this revolutionary technology: it’s not just for insulin-using patients, it’s for all patients. Yes, there are some very obvious benefits for insulin-using patients. However, this technology is still valuable for a patient on orals alone or orals plus insulin. The difference is how each subset of patients will use and interact with their CGM. While intensively-managed insulin using patients will use CGM 24/7/365, less intensively-managed patients may only use CGM once or twice a month.
With less intensively-managed patients, CGM is first used as a discovery tool to find out what’s going on. Next, it’s used as a validation tool: we discovered what’s going put a plan in place to handle what’s going on, validate what we did, and make sure it’s working. Finally, it will be used as a maintenance tool, to make sure the plan is working and that no adjustments need to be made.
The bottom line here is that CGM provides real evidence and a clear view. The patient and physician can now SEE what’s going on, with no more guessing and no more relying on just HbA1c alone to make decisions. Ultimately, this is why we see CGM as the most transformative technology ever invented for patients with diabetes and their physicians. CGM brings light where only darkness existed before.
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