AINsight: Diabetes and Flying

 - December 13, 2019, 11:49 AM

Diabetes Mellitus is a disease that involves impaired glucose metabolism. Sudden adverse changes in blood glucose (high or low) can lead to altered mental status, to seizures, and even death. Long-term complications include damage to “end organs,” such as eyes, kidneys, heart, and the neurological system.

Further, this is a condition that would render an existing medical certificate invalid from the moment the pilot knew of the diagnosis, regardless of any theoretical period of validity that might appear to remain for that certificate.

Are all pilots with diabetes grounded indefinitely? Is there any hope for a pilot with diabetes to fly again? What about commercially?

The answers are reassuring. Private pilots with well-controlled diabetes have been flying for many years. And a recently implemented program with the support of the Federal Air Surgeon will now enable even more diabetics to return to commercial flying.

Without going into an elaborate explanation of its physiology, let’s break diabetes down into two categories: non-insulin-dependent and insulin-dependent.

Insulin is a hormone that is released by the pancreas in response to blood glucose levels. All body tissues use glucose for energy. When blood glucose rises, the pancreas secretes insulin, permitting the bodily tissues to store and use glucose for various metabolic functions.

In certain cases of diabetes, the production of insulin is significantly decreased or completely absent. Common names include juvenile, type 1, or insulin-dependent diabetes (IDDM). Don’t let the term “juvenile” confuse the situation, as there are times when insulin dependence might not occur until well into adulthood.

The relevant premise here is that the body has stopped producing sufficient insulin to regulate blood glucose, regardless of the person’s age. You might also see the term insulin-treated diabetes (ITDM) in various publications, and for the purposes of FAA medical certification, IDDM and ITDM can be used synonymously.

In other cases, the bodily tissues have become resistant to the insulin that the pancreas is dutifully producing (obesity is a common cause of insulin resistance). Terms familiar to most people include adult-onset, type 2, or non-insulin-dependent diabetes.

Google “mellitus” for the amusing reference of how that word became part of the lore of diabetes centuries ago. I will provide more pathophysiologic information when I discuss the individual types of diabetes and the respective FAA certification programs more specifically in future submissions.

Therefore, I won’t go into the formalities and minutia of how to diagnose, treat, and monitor diabetes in this discussion. Suffice it to say that poorly-controlled diabetes poses a significant threat to aviation safety, not to mention long-term health.

Diabetes that can be controlled with diet, exercise, and weight loss is the proverbial no-brainer in FAA medical certification. Anything a pilot can do without medical intervention is always preferable for long-term health maintenance.

All classes of medical certificates can be easily obtained in this setting and usually a special issuance is not required (at times this is followed through a slightly amended protocol for “pre-diabetes” that I’ll discuss at a future date).

The necessity for oral and some of the injectable non-insulin medications that lower blood glucose to control diabetes also does not preclude FAA medical certification. In this case, while the pilot will be followed under a special issuance authorization, all classes of medical certificates are again included in this protocol. I have had many pilots flying commercially on first- and second-class medical certificates for many years who are taking oral diabetic medications.

If a pilot requires insulin, however, things change. Before 1996, any insulin-dependent pilot was unable to fly (all classes of medical certificates were excluded). Beginning in 1996, pilots could obtain a third-class FAA medical certificate if they are taking insulin and their diabetes is “well controlled.”

Fortunately, the program for third-class IDDM pilots has been a great success. The very rare adverse in-flight incidents over the years with diabetic pilots usually have occurred in pilots with poorly controlled diabetes who likely would not have been granted a special issuance authorization in the first place.

A pilot who requires insulin for treatment has been excluded for classes of FAA medical certificates higher than third-class until just recently. I have been a vocal advocate to the FAA and its various Federal Air Surgeons over the years that well-controlled IDDM pilots should be considered for first- and second-class certification.

With the current precise continuous glucose monitoring (CGM) electronics and advancements available, an insulin-dependent diabetic is now able to maintain tightly-controlled blood glucose levels.

In 2002, Canada began permitting IDDM pilots to fly commercially in a multi-pilot crew environment. The UK began doing so in 2012, and now the U.S. joined that group last month (on November 7).

Notably, there is no restriction in the FAA protocol that an IDDM pilot must be in a crew environment. Thus, an FAA-licensed pilot with a special issuance for IDDM can fly single-pilot so long as all provisions are met. The FARs don’t permit the FAA to put restrictions such as “must be part of a multi-pilot crew” on first-class medical certificates.

There are also several other countries that permit private flying in pilots with various forms of diabetes.

As you can imagine, the FAA was very cautious and reviewed the advances in diabetic management technologies methodically over many years before authorizing this new program. No different than any other special issuance program, the FAA did not want aviation accidents resulting from a poorly conceived program.

This would, of course, be a tragedy for anyone involved in the accident and could jeopardize the entire program itself. Out of respect for caution, the FAA spent many years working on this program. And now, it’s finally here!

However, the requirements are probably the most extensive of any special issuance program that we have. There will be ongoing evaluations of numerous organ systems. In addition to using the latest technology to monitor and treat a pilot's diabetes, evaluations will be ongoing for eyes, heart, kidneys, and neurological systems.

The data presentation to the FAA is also extensive and thorough. As with some of the other special issuance conditions, the FAA has developed comprehensive checklists—for pilots, their AMEs, and the treating physicians—and flow sheets to assist in the detailed data presentation to the FAA. Ongoing CGM data will also be required.

As exhaustive as this program is, it has finally opened the world of commercial flying to IDDM pilots who require a first- or second-class FAA medical certificate. I am hopeful that the program will be as successful as the earlier program for third-class pilots has been.

Those with IDDM are often some of the most motivated pilots there are, and the new gadgetry involved has demonstrated to the FAA that precise control of diabetes can indeed be achieved and, therefore, such pilots do not pose a threat to aviation safety. Thus, it is predicted that IDDM pilots will be able to fly safely in commercial operations—on first- and second-class special issuance authorizations—in the U.S.

For a pilot to obtain a special issuance authorization under this new IDDM protocol, they will need an organized and motivated team of support. The pilot, first and foremost, must adequately control their diabetes using modern electronics, including CGM devices, as that also will improve the likelihood of maintaining long-term health.

Next, the treating physician must be willing to complete thorough FAA flow sheets and, at select times, consulting physicians will have to provide evaluation data of the other organ systems mentioned above. Finally, the AME must be willing to choreograph all of the data into a packet that will be acceptable to the FAA.