Medical Stuff: The AME's Definition of Hypertension

By Donato Borillo, MD, JD
Reprinted with permission from FAA Aviation News
This article originally appeared in the Federal Air Surgeon's Medical Bulletin

High blood pressure is a risk factor or a cause of more than 210,000 deaths in the U.S. each year and is often called the silent killer.

There is a saying among aviators, 'Being legal does not mean you're safe or proficient.' The same axiom holds true regarding high blood pressure, since recent changes in this disease's definition seemingly conflict with FAA regulations.

Aviation medical examiners (AMEs) understand the measurement of blood pressure as an essential part of the FAA medical certification examination. A pilot is disqualified for all classes if she, or he, has a sitting systolic blood pressure above 155 mm mercury at the time of the exam.

However, on May 14, 2003, the National Heart, Lung, and Blood Institute (NHLBI), a division of the Department of Health and Human Services and National Institutes of Health, issued new blood pressure standards. [Note: The Seventh Report of the Joint National Committee on Prevention, Detection, Evaluation, and Treatment of High Blood Pressure (JNC 7).]

As defined by the NHLBI, a blood pressure of 120/80 mmHG (or higher) is now considered pre-hypertension; a precursor condition to hypertension, which serves as a warning signal that risk is increased for high blood pressure. The new report also changes the former blood pressure definitions.

The new guidelines also recommend a change in medication use. [Note: Simplified and strengthened drug treatment recommendations. The guidelines recommend use of a diuretic, either alone or in combination with another drug class, as part of the treatment plan in most patients. The report notes that even though many studies have found diuretics to be effective in preventing hypertension's cardiovascular complications, they are currently not being sufficiently used. The guidelines also list other drug classes that have been shown to be effective in reducing hypertension's cardiovascular complications and that may be considered to begin therapy; angiotensin converting enzyme (ACE) inhibitors angiotensin receptor blockers, beta-blockers, and calcium channel blockers. The report also gives the 'compelling indications''or high-risk conditions'for which such drugs are recommended as initial therapy. Use of additional drugs for severe hypertension or to lower blood pressure to the desired level. According to the new report, most persons will need two, and at times three or more, medications to lower blood pressure to the desired level.]

An aviator could therefore, have untreated stage 1 hypertension (and possibly stage 2 hypertension) and still be within the medical standards'to fly.

We know that pilots with a diagnosis of hypertension or those on medication to control blood pressure must provide a detailed cardiovascular evaluation for FAA consideration. So, what's an AME to do? And, does this 'new definition' imply an increased risk for sudden incapacitation (the underlying factor for medical disqualifications)?

The simple answer is, no. The AME should identify the elevated, but legal, blood pressure, inform the airman applicant of its health impact, and make recommendations for life style changes and medical follow-up. The AME should refer the patient back to his, or her, primary care physician and may issue the certification. If the AME happens to be the primary care provider for the aviator, a work-up for essential hypertension should be conducted.

If a diagnosis of high blood pressure is subsequently made, or anti-hypertensive medication is initiated, these actions effectively suspend the medical certificate, since this would be consider a significant change in medical condition or history. Pilots with a diagnosis of hypertension or those on medication to control blood pressure must provide a detailed cardiovascular evaluation for FAA consideration.

The consequences of high blood pressure, if left untreated, should be stressed to the aviator, since damage to major organs, including the heart, brain, and kidney may occur. It is a major risk factor in heart failure, heart attack, stroke, kidney failure, and certain kinds of blindness. High blood pressure is a risk factor or a cause of more than 210,000 deaths in the U.S. each year, and is often called the silent killer.

Although it is legal to fly with pre-hypertensive condition, it may not be healthy in the long run.

Dr. Borillo is the Medical Director of Occupational and Hyperbaric Medicine, The Toledo Hospital, ProMedica Health System. He is also a senior aviation medical examiner, an attorney, and a pilot with a Commercial rating.