What is hypertension?
Hypertension is another name for high blood
pressure. It occurs when the pressure inside the arteries is too high.
This causes strain on the arteries, which can result in them becoming
clogged or weakened. This in turn can lead to damage to the heart and
other organs in the body.
People who have hypertension which is not
treated are more likely to suffer from complications such as stroke, heart
attack, heart failure, heart rhythm irregularities and kidney failure,
than people who have normal blood pressure.
What causes hypertension?
High blood pressure can affect anyone, and
it does tend to increase with age. Often no cause is found, but you are
more likely to develop hypertension if:
You have a family history of hypertension,
stroke or heart attack,
You are overweight, eat too much salt and
not enough fruit and vegetables, take little exercise or drink too much
You have certain conditions such as
diabetes, kidney disease or heart disease.
How is hypertension assessed?
Hypertension usually has no signs or
symptoms. The only way to determine if you have hypertension is to have
your blood pressure measured, and this will always be done at your medical
examinations. Although this is a simple process, it is important that it
is done correctly. If the reading is made while you are agitated,
frightened, excited or angry, it may be high due to your emotional state.
If your blood pressure is recorded as high
when taken by a doctor, but is normal when you are at home, it is called
“white coat hypertension”. To check if you have this, you may be asked to
wear a blood pressure monitor for 24 hours. This will provide a record of
blood pressure away from the clinical setting, and will determine whether
you really have high blood pressure or not.
Your blood pressure is represented as two
numbers. The first is called the systolic pressure and indicates the peak
pressure in your arteries generated when your heart beats. The second is
the diastolic pressure and indicates the residual pressure in your
arteries when your heart is relaxed between heartbeats.
The American Heart
Association has recently redefined blood pressure standards. The old myth
that blood pressure should rise with age is false. The AHA standards based
on considerable research do not make allowances for age. Many studies lead
to the conclusion that the lower an individual’s blood pressure is, the
lower the risk of heart disease. This is especially true for elevated
levels, but holds true within the normal range also, The current standards
are summarized below:
The Seventh Report of the
Joint National Committee on Prevention, Detection, Evaluation, and
Treatment of High Blood Pressure approved by the National Heart, Lung, and
Blood Institute updates guidelines for the prevention and management of
hypertension as of May 2003. These recommendations advocate even lower
levels than those listed above by the AHA.
FAA Blood Pressure Standards
The FAA’s upper limit for blood pressure previously varied depending on a
pilot’s age and class of certificate. The standards now allow
certification for pressures up to 155/95 without an evaluation. Pilots
with blood pressures above this level may still be certified after a
cardiovascular evaluation (CVE). The standards set by the FAA should not
be construed as healthy or "safe" levels. They are maximum levels. Blood
pressure near these limits should be evaluated and treated as per the AHA
The FAA delegated the authority to waive use of blood pressure medication
when flying to the Aviation Medical Examiners (AME) if a Cardiovascular
evaluation is otherwise normal. This change is to encourage pilots to get
their elevated blood pressure evaluated, and treated if necessary, without
reluctance due to medical certification issues.
The maximum allowable blood pressure for controllers age 20-29 is 140/90;
age 30-39 is 150/90; age 40-49 is 150/100; and age 50 and over is 160/100,
although a normal blood pressure is much lower at 120/80.
For controllers, the FAA generally requires three blood pressure readings
in the acceptable range before reinstating your medical qualification with
Special Consideration. Once returned to controlling duty, the Regional
Flight Surgeon will require an annual report from your treating physician
regarding your current medications and blood pressure readings.
Initial Treatment Without Medication
Several steps not involving the use of prescription medications are nearly
universally recommended for all people evaluated for hypertension. Risk
factor modification prior to the use of medication is desirable, although
somewhat difficult for some. These steps include achieving ideal body
weight, lowering salt, fats and cholesterol in the diet, increasing fibre
and heart protecting nutrients in the diet, participation in an exercise
program with your physician’s recommendation and stopping use of tobacco
One study found morning caffeinated coffee raised blood pressure all day.
Other testing is designed to look for treatable cause of hypertension such
as thyroid disease, narrowing of the aorta or renal arteries, endocrine
tumours and diabetes. Co-existent medical conditions should be treated. A
study from Duke University in the American Heart Journal reports that
depression is associated with poor blood pressure control.
Undiagnosed obstructive sleep apnea may be a cause of hypertension.
Treatment for sleep apnea may improve blood pressure and lower risk
factors for other diseases, as well as improving alertness and a sense of
well being. An article, patient handout and editorial in American Family
Physician, Jan 15, 2002, explains more about this phenomenon. Individuals
with sleep apnea are disqualified from flying and controlling by the FAA
until an acceptable treatment documents improvement in the condition.
Search for the VFS article on Sleep Apnea.
Patients interested in self-monitoring should be aware that electronic
home monitoring is easy. However, of the many devices available
commercially very few have actually passed reliable validation tests (a
list is available online at www.dableducational.com). The American Heart
Association does recommend devices with a memory or printouts be used.
FAA Cardiovascular Evaluation
The CVE required by the FAA may be performed by any treating physician,
not necessarily the AME or a cardiologist. Note that the maximal stress
test specified in FAA Protocol for Evaluation of Hypertension, is
optional. It should be performed IF CLINICALLY INDICATED. If your
physician recommends additional tests BECAUSE THEY ARE MEDICALLY
INDICATED, do the testing and protect your health. We strongly advised
AGAINST doing testing that is not medically indicated "just because the
FAA might want to see it." If the FAA wanted it, they would ask for it.
Extra testing can cause significant problems, administrative delays and
The cardiovascular evaluation includes:
1) pertinent personal and family medical history
2) assessment of risk factors for heart disease
3) clinical exam with at least 3 BP readings
4) resting ECG
5) lab reports including fasting glucose, cholesterol (HDL & LDL),
triglycerides, potassium and creatinine
6) Exercise stress test, IF clinically indicated
7) Report of medications, dosage, any side effects
FAA Policy on Blood Pressure Medications
If after the evaluation, your physician feels medication would be
appropriate for your condition, many options exist. The FAA does not
authorize some medications used mainly in the 1950’s and 1960’s, namely
guanethidine, reserpine, guanadrel, guanabenz and methyldopa. All other
blood pressure medications that have been FDA approved are currently
authorized, as are new reformulations of previously approved medications.
Before flying on any medication, the pilot should tolerate the medication
well without significant side effects. Provide reports from the treating
physician to your AME at the time of your next physical to fly. Reports
may also be sent to the FAA for approval. Controllers are also required to
submit documents to the Regional Flight Surgeon.
Different classes of medication and combinations of classes are prescribed
to control blood pressure. The determination of which medication to
prescribe depends on many factors. These factors include findings during
the exam, co-existing medical conditions, lifestyle issues and even
insurance coverage. A brief discussion of each major class of
antihypertensive medication follows with a partial list of some
medications in each class. New medications are continuously marketed,
which is why the FAA does not attempt to publish a listing of "approved"
medications. See the VFS Medications section for more information.
Diuretics are also know as "fluid pills". They increase urination and may
decrease circulating blood volume. ("The lower the oil level, the lower
the oil pressure"). Diuretics are generally well tolerated without side
effects and are inexpensive. For these reasons, they are frequently a
first-line recommendation for treating hypertension. Some diuretics
increase the urine’s output of potassium (K+). Pilots on these diuretics
will periodically have to report their blood potassium level to the FAA.
Some diuretics in this subcategory include hydrochlorothiazide (HCTZ),
furosemide (Lasix), Zaroxyolen and Diuril. Often these medications are
combined in one pill with medications from another category for ease of
use. Some diuretics are known as "potassium sparing." These include
Triamterene and Aldactone. Other diuretics combine the potassium wasting
and potassium sparing characteristics in one pill, such as, aldactazide,
Dyazide, Maxzide and Moduretic.
Beta blockers work by interfering with the nervous system's signals to the
beta adrenergic nervous system. This part of the nervous system sends
signals to increase the heart rate and dilate the bronchioles of the lungs
in preparation for the primitive "fight or flight response." By blocking
this response, the heart rate slows and blood pressure falls, just like
turning off the boost pump. This is the only category of medication proven
to protect against a second heart attack and may have protective effects
against a first heart attack.
Because the maximum heart rate is limited, pilots on this medication may
have difficulty achieving their maximal predicted heart rate on treadmill
stress tests. These medications are usually well tolerated but a small
number of people will experience fatigue and decreased sexual function.
People with diabetes or asthma should not take these medications unless
specifically discussed with your physician. Examples of beta blockers
include propanolol (Inderal), metoprolol (Lopressor, Toprol -XL), atenolol
(Tenormin) and bisoprolol (Zebeta).
Alpha blockers work by interfering with the nervous systems signals to the
alpha adrenergic system. This part of the nervous system acts on the
smooth muscles of the blood vessels and other parts of the body. When
stimulated, the smooth muscles cause the vessels to constrict. The alpha
blockers cause dilation of the vessels, increasing the available volume of
the circulatory system and decreasing pressure. Think of them as adding a
sump to the oil system without adding any oil. They are very effective in
lowering blood pressure, but may do so too quickly, particularly when just
starting the medication. The result may be noticeable light-headedness
when getting up, and even fainting, when just starting the medication. To
avoid this side effect, most physicians initially prescribe reduced doses
of the medication at bed time, gradually increasing the dose as tolerated.
The alpha blockers are also used to treat prostatic hypertrophy and
increase urine flow. They may be an excellent choice for a male with both
hypertension and prostatic hypertrophy as single drug treatment for both
conditions. Examples include doxazosin (Cardura) and terazosin (Hytrin).
Angiotensin Converting Enzyme (ACE) inhibitors block the formation of a
series of compounds produced in the kidney that raise blood pressure. The
kidney regulates blood pressure with chemicals secreted in response to how
much blood flows into the kidneys. If the pressure is low, ACE is one of
several chemicals in a cascade that triggers the body to retain more fluid
and increase blood pressure. Inhibiting this cascade fools the body into
thinking there is plenty of blood pressure for the kidney and shuts down
the reaction to increase blood flow.
Because of the association of hypertension and kidney disease with
diabetes, ACE inhibitors are an excellent first drug to use in individuals
with both conditions. Black individuals do not respond as well to ACE
inhibitors as do whites. The major side effect is an annoying and
persistent cough in approximately 3-5 % of people using the medication.
Examples of ACE inhibitors include lisinopril (Prinivil, Zestril),
enalapril (Vasotec), captopril (Capoten), benazepril (Lotensin),
fosinopril (Monopril), quinapril (Accupril) and ramapril (Altace).
Angiotensin Converting Enzyme II is another chemical in the cascade
mentioned above. The mechanism of action is similar, though at a different
step in the process. The side effects from this category seem to be
minimal. Examples include losartan (Cozaar, Hyzaar, Diovan).
Calcium Channel Blockers
Calcium channel blockers work by impeding the flow of calcium into the
muscles of the cardiovascular system. This interferes with the contraction
of the blood vessels and slows electrical activity in some parts of the
heart. This effect of the heart’s electrical activity may be beneficial in
persons with arrhythmia's (irregular heart rates) as it can simultaneously
keep the heart rate and blood pressure controlled. The major potential
side effects are headache and peripheral edema, swelling of the hands and
feet. Examples include nifedipine (Adalat CC, Procardia XL), verapamil (Calan,
Covera-HS, Verelan, Isoptin), amlodipine (Norvasc), nisoldipine (Sular)
and diltiazem (Cardiazem).
FAA Clearance to Use Medications while
Pilots and controllers may get clearance to fly and control on these
categories of medications from their AME or from the FAA following
completion of the CVE and documentation that their blood pressure is well
controlled without side effects after several days on their final dose of
medication. The FAA has a web site with information of certification of
individuals with hypertension.
Combinations of antihypertensive medications are also authorized for any
class of FAA medical certification. An article and editorial in American
Family Physician discusses the potential benefits of combination therapy
in high risk individuals. Because hypertension is a risk factor for many
more serious medical conditions,Al pilots and controllers
with hypertension are encouraged to seek appropriate evaluation and treatment for the
condition and optimize the opportunity to retain a medical certificate for
The FAA AME aeromedical decision protocol for hypertension allows the AME
to issue a certificate after completion of an appropriate evaluation. The
completed Cardiovascular Evaluations listed on FAA Protocol for Evaluation
of Hypertension and other test results may be mailed to the FAA at:
Federal Aviation Administration
Aeromedical Certification Division
CAMI Bldg./ AAM-300
P.O. Box 26080
Oklahoma City, OK 73126-9922
However, without careful review, direct submittal often can result in
significant delays in certification while the FAA asks for clinical
clarification. Often well-meaning specialists who are not trained in
aerospace medicine fail to address all the aeromedically important aspects
of a particular case. As a result, the case is returned without action
pending further documentation, or worse the pilot receives a potentially
This is a very broad overview of a complex subject with many nuances.