Insulin-Dependency in Aviation

Editorial, by Jon L. Jordan, MD, JD

For the most part, FAA medical certification practices and policies are not controversial within the medical community. For most medical conditions, our special issuance, or waiver process, allows for individualized determinations. As a result, persons with a known history of significant cardiovascular disease, alcoholism, and so on, have been issued medical certificates upon showing that their conditions do not jeopardize aviation safety. There are, however, a few exceptions to individual consideration that are controversial.

One such condition is diabetes mellitus where insulin is required for control. Current FAA policy precludes certification of airmen in these circumstances. Over the years, however, approximately 20 insulin-dependent FAA air traffic controllers have been permitted to perform their safety-related duties. Nevertheless, because several hypoglycemic reactions occurred among these controllers, it was deemed necessary to withdraw their medical clearance several years ago. This created substantial criticism from the controllers, their physicians, and the American Diabetes Association.

Accordingly, the FAA last year convened a panel of nationally-recognized endocrinologists to determine whether some protocol could be established to identify those diabetics controlled with insulin who were at low risk for hypoglycemic reactions and who could be medically cleared to safely perform air traffic control duties.

The panel concluded that such is possible--if the controller has no:

  • complication of diabetes mellitus likely to interfere with the ability to safely control air traffic
  • history of severe hyupoglycemic reaction resulting in loss of consciousness or seizure
  • recurrent severe hypoglycemic reaction requiring intervention by another party during the last five years
  • history of recurrent hypoglycemia resulting in impaired cognitive function, without warning symptoms (hypoglycemia awareness).
The FAA, using the panel�s recommendations, allowed 10 diabetic controllers maintained on insulin to resume their air traffic control duties. To provide an adequate basis for medical clearance, each controller is required under the protocol to provide any hospital records, reports of accidents caused by diabetes, and the results of an endocrinologist�s medical evaluation that include two readings of glycated hemoglobin during the prior three months.

Also required: confirmation by an ophthalmologist of no diabetes-related retinal disease, the results of an examination to detect peripheral neuropathy, and a detailed report of insulin dosages and diet utilized for control. It is also required that the controller be educated in diabetes and its control.

Under the protocol, individuals are required to be examined by a specialist every three months, to carry and use a digital, whole blood glucose monitoring device with memory, and to provide the results of an ophthalmological evaluation annually.

For health and safety reasons, controllers are not permitted to work alone. They are required to test their blood glucose concentration one-half hour prior to assuming duties and approximately every two hours during work.

If a controller�s blood glucose falls to less than 60 mg/dl (milligrams per deciliter), he or she is required to stop work, consume an appropriate snack containing glucose, and recheck blood glucose in 30 minutes. If the blood glucose at recheck is 60-99 mg/dl, the individual is required to eat an additional snack and recheck in 30 minutes. This process is repeated until the blood glucose level reaches 100 mg/dl, or greater.

If the level is 100-300 mg/dl, no action is required, but if 300-400 mg/dl, an appropriate dose of insulin is to be taken. If over 400, the controller is directed to cease work and take appropriate action.

About a year has elapsed since the insulin-dependent controllers have returned to their duties. We are now gathering data related to the control of their diabetes and any operational problems that may have been encountered.

Further recommendations are anticipated from the endocrinologists who established the controller assessment and monitoring protocols.

It appears likely that these endocrinologists will also consider whether it is appropriate to recommend that similar protocols be extended to pilots.

The FAA continues to receive petitions from many sources, including the American Diabetes Association, to consider allowing certification of insulin-dependent airmen. Of course, any change in our policy on insulin use by airmen must not compromise aviation safety.

JLJ