Just what is good control?

Just what is good control?

For as long as we can remember HbA1c has been considered the gold standard for measuring whether a patient with diabetes is under good control. There are several reasons for this not the least of which being the mountain of clinical data that has shown the relationship between A1C and complications. Yet there is another reason A1C has become the gold standard, the number is actionable.

As we have been noting for some time one of the biggest issues with interconnected diabetes management (IDM) is transforming data into patient relevant, patient actionable information. This is the same reason why the majority of patients fail to monitor their glucose levels regularly. We have long argued that this is one of the reasons why even if there was such a thing as non-invasive glucose monitor this device would not increase testing frequency. The simple fact is the reason patients don’t test more frequently has nothing to do with the “pain” associated with performing the test. No the reason is the information gained from the test is not relevant to the patient.

It should come as no surprise that average testing frequency corresponds directly to which therapy regimen the patient is following.  This is why insulin pump patients are the most frequent testers averaging nearly 7 tests per day, followed by patients following multiple daily injection (MDI) therapy and so on. The fact is insulin using patients value this information as its needed so they can properly dose their insulin. There is an action step performed based on the test results. This is also the reason why insulin pump and MDI patients are the primary users of continuous glucose monitoring systems.

This is in sharp contrast to a non-insulin using patient as rarely is there an action step taken based on test results. The obvious exception being a patient experiencing a hypoglycemic event. Yet other than that exception there isn’t much a non-insulin patient can do should the test reveal the patient is not in the proper range. This does not mean that these non-insulin patients should not test their glucose levels regularly rather a single data point by itself is meaningless.

Diabetic Investor has long argued that even though these non-insulin using patients don’t act on the test results gathering this data is as valuable as it is for insulin using patient. Since the advent of CGM technology there is growing consensus of the importance of understanding glycemic variability. The importance of not a single data point rather a series of data points. Understanding glucose trends yields valuable insights into how a patient is doing and in some respects is actually a better method for determining whether the patient is actually under good control.

Still the uptake of CGM technology with non-insulin patients has been painfully slow. While there are several reasons for this one has to do with data analytics. Again transforming all these data points into patient relevant, patient actionable information. This again is in sharp contrast to A1c which is an easy number for the patient to understand and is actionable. An A1c result of 7 or below is good, no action needed, a result of 7 or above not so good, action may be needed.

Over the years’ numerous studies have concluded that there is no correlation between increased testing frequency and better outcomes for non-insulin using patients. These studies have given payors cover to limit the number of test strips they reimburse for non-insulin using patients. These same studies are also the reason Diabetic Investor believes that it’s not a question of if payors will stop reimbursement for non-insulin using patients but when they will stop.

Given this set of circumstances we found yesterday’s announcement from the American Association of Clinical Endocrinologists (AACE) very interesting. According to a press release;

“Citing glycemic measurement as an essential component of care for all patients with diabetes, the American Association of Clinical Endocrinologists (AACE) today announced the publication of its outpatient glucose monitoring consensus statement.

The statement provides detailed analyses to support precise recommendations for the type of system and frequency of use for either self-monitoring blood glucose (SMBG) therapy or continuous glucose monitoring (CGM) to reduce short- and long-term complications of diabetes.”

The full statement which can be found at  http://journals.aace.com/doi/full/10.4158/EP151124.CS contains the following passage;

“Patients and clinicians should be educated to understand and use GM data. Glucometric data analysis can help both patients and clinicians assess the quality of glycemic control, identify glucose patterns and responses to therapy, and evaluate glucose variability. Glucometric analysis can also be used as an educational tool. Education is essential to making apparent the relationship of specific glucose data with medication and other therapeutic interventions.”

Basically what AACE is saying is what Diabetic Investor has been stating, that collecting data is the easy part, turning this data into patient relevant, patient actionable information is what’s important. We also found it interesting the statement specifically noted the importance of identifying glucose patterns and evaluating glucose variability.

What is AACE is acknowledging with this statement is HbA1c the current gold standard for determining what constitutes good control is an incomplete gold standard. That as easy as this number is to understand and act upon it does not tell the whole story.   That the definition of what constitutes good control may need to be expanded beyond just A1c and include a measurement for glucose variability. That it is just as important to keep a patient in a tighter glucose range than it is to keep their A1c at 7 or below. That these two measurements, HbA1c and glucose variability, should be used TOGETHER. That when used together they will provide a better picture for when a patient is or isn’t under good control.

One person who won’t be surprised by this statement and not just because he was on the task force, is Dr. Irl Hirsch. Dr. Hirsch is one of the most respected researchers on the topic of glycemic variability. Diabetic Investor can remember sitting in a presentation given by Dr. Hirsch when he showed two patients both with A1c’s of 7 yet one who’s glycemic pattern (variability) was in a tight range the other who’s pattern looked like a chart of MannKind ‘s (NASDAQ: MNKD) stock price. His argument then, and this was years ago, was looking at A1c alone one would think both patients were under good control when in reality this was not the case.

Since that time additional studies have shown the correlation between glycemic variability and complications. Basically adding credence to what Dr. Hirsch noted years before, namely that HbA1c by itself does not tell the whole story.

The statement by AACE and the lessons learned from Dr. Hirsch should not be lost on the companies in the IDM space.  As the AACE statement notes clearly data by itself is not the answer and “EDUCATION IS ESSENTIAL”. As Momma Kliff used to say data alone is worthless, data combined with education leads to knowledge. With knowledge patients can and will take action. Like Dr. Hirsch Momma Kliff was not just well ahead of the curve, she was also spot on.