Over-treat Your Blood Pressure and You Could Die Sooner
John McDougall, MD
If you have high blood pressure, your doctor may insist
that your blood pressure must be lowered all the way to “normal” (110/70
mmHg* or less) – but he’s dead wrong. And no matter how much the
pharmaceutical companies protest with their billions of dollars of
marketing money for research and advertising, over-treatment of your
hypertension increases your risk of heart attacks, strokes, and early
(*mmHg means “millimeters of mercury” and is the means
of expressing blood pressure)
Do not confuse this discussion with naturally-occurring
low blood pressure. Without medications a normal blood pressure is 110/70
mmHg or less – and that level is associated with great health.
Lying with Statistics
Your doctor may tell you that by treating your high
blood pressure with drugs you will cut your risk of a stroke almost in
half. You think, “I’d be a fool to take that risk. If I don’t take the
pills I will certainly have a stroke and the medication is unquestionably
The truth is this:
If you have mild hypertension (diastolic – lower number
– of 90 to 110 mmHg) your risk of a stroke over the next 5 years is 15
chances of every 1000 untreated patients (or 1.5 in a 100).1
If you take medication, then your risk for a stroke is 9
chances out of every 1000 treated patients for the next 5 years.
Now that is a relative risk reduction of 40% (15 - 9 /
15)1 – And if someone told you that you could reduce your risk of having a
stroke by 40%, you might jump at the opportunity.
But in real life (absolute) numbers this is not so
impressive. Consider that if you treat 1000 people with drugs for five
years, the benefit is only six fewer strokes (15 vs. 9). In other words,
by spending thousands of dollars and suffering the side effects (which may
include impotency, weakness, or worse) you might reduce your absolute risk
of having a stroke over the next five years by less than 1%. (Actually,
the reduction is 0.6 in a hundred for five years, which calculates out to
about one in a thousand fewer strokes per year of treatment.)
You Deserve Better Than Drug Therapy Can Offer
Faced with these numbers you might think again. Or
better yet you might decide that a change in diet and lifestyle, which
costs nothing, with no side effects and far greater benefits, might be
well worth all your efforts (especially since you now realize you are not
going to be saved by the pharmaceutical industry).2
Treatment of elevated blood pressure with medications
has some benefits; but, aggressive treatment does not bring risks even
close to normal. For example, over a 3-year period, men (40 to 59 years
old) were found to have a 21% risk of death from stroke and a 20% risk of
death from a heart attack even though their pressure was reduced from
183/114 mmHg to a level of 149/91 mmHg with medications.3 This compares to
a 1% risk of death from either disease for people without hypertension
(133/80 mmHg) over this same 3 year trial period. The obvious conclusion
is you want to be a person without hypertension and you accomplish that
goal for free by following a healthy diet and lifestyle.
The J-Curve of Mortality
Many studies of people treated for elevated blood
pressure with medications have shown that when blood pressure is reduced
below a certain level, risk of serious trouble (heart attacks, strokes and
deaths) will increase.4-15 This relationship is referred to as a
“J-shaped” curve. Meaning: lowering the pressure to a certain point is
beneficial (that is the first part of the “J” shape), but beyond that
point, the patient is harmed (the second part of the “J”) when the
pressure is lowered further toward “normal.” This phenomenon is found with
both systolic (top number) and diastolic (bottom number) pressure changes.
Data presented at the 2004 annual meeting of the
American College of Cardiology reaffirmed the “J-curve.”16 A study of
22,576 patients treated for hypertension showed that the death rate
dropped until a nadir (lowest point) was reached at a diastolic pressure
of 84 mmHg. When the diastolic pressure fell below 84 mmHg, then patient
deaths and heart attacks rose again. For example, those with a diastolic
of 70 mmHg had 20% greater risk, at 65 mmHg the risk was 80% greater, and
at 55 mmHg the risk was four times higher than at 84 mmHg.
People treated for isolated systolic hypertension (a
case where the systolic pressure is high, but the diastolic is normal or
low) are particularly vulnerable to the harms from over-treatment.17,18
Your well-meaning doctor has been taught by the pharmaceutical companies
that it is the duty of every good physician to make patients’ blood
pressures normal at all costs, even when the top number is the only one
out of range. Two studies have shown that the J-curve applies to isolated
systolic hypertension and the risk of strokes, too. The Systolic
Hypertension in Elderly Program study found a 14% increase in strokes in
those whose diastolic pressure was lowered only by 5 mmHg with medications
(starting average of 177/77 mmHg).19 Overall, the research suggests the
greatest benefit for stroke prevention is to reduce the diastolic blood
pressure no lower than 85 mmHg.17
Why Low BP Kills
The reason too aggressive treatment of hypertension with
medications causes serious harm is because the artificially lowered blood
pressure impairs the flow of blood to the tissues of the heart and
brain.5,15 The small blood vessels supplying these vulnerable tissues are
the ones most affected. The flow of blood to these vital organs can become
low enough to cause death of tissues, resulting in a heart attack or
stroke. Even before the point of causing death of the heart muscle, an
inadequate blood supply can cause irregular heartbeats (arrhythmias) of
the heart, which are often fatal. Therefore, great caution must be taken
in order to prevent lowering blood pressure too much when medications are
Dumber You Will Be Too with Over-Treatment of BP
In line with the recent findings that blood pressure
medications compromise the circulation to vital tissues, a recent study
found low treated blood pressure was associated with poor thinking, and
mild hypertension was associated with better thinking.20 By
over-aggressive lowering of blood pressure with medication function of the
brain in the elderly was found to be impaired. The best brain function was
associated with a blood pressure of about 159/85 mm Hg (a level consistent
with the lowest risk of strokes, heart attacks, and deaths). This loss of
intelligence may be permanent in some cases. Just published in the journal
Stroke are the findings that patients whose systolic blood pressure (the
top number) dropped 15 mmHg or more in six years or less had triple the
risk of Alzheimer's disease, or other forms of dementia.21 Their findings
indicate that poor blood flow to the brain, resulting from a decline in
blood pressure, in some cases from over-treatment with anti-hypertensive
medications, promotes permanent loss of brain function – dementia.
How I Treat Hypertension
When I find a patient has an elevated blood pressure
reading in my office, my approach is to recommend the following to the
1) Don’t panic; your high blood pressure may be
secondary to excitement, stress, pain or another reaction completely
unrelated to the health of your arteries; and it likely will normalize on
2) Begin taking your blood pressures at home and record
the results so that we can discuss them later. Blood pressures obtained in
an office setting are notoriously inaccurate, because of the “white coat
3) Obtain other information that may help establish your
level of risk for future health problems – these are called “risk factors”
and are such well-known measures as body weight, and blood cholesterol,
triglycerides, and sugar.23 A patient’s history and physical examination
are also very helpful in determining the urgency to treat. The decision to
treat is a judgment (best guess) that is made by the doctor, and should be
made with the patient’s full participation in this decision – after all
this is usually a lifetime commitment.
4) Doctors usually say that once you are on medications
for blood pressure you will be on them for life. This is true only if you
fail to understand three important things: 1) the actual benefits and
risks of these medications; 2) the fact that a healthy diet will lower
blood pressure to normal in most cases and medications can be stopped; and
3) exercise and associated weight loss are also powerful tools for
reducing blood pressure and improving general health. Therefore, I
strongly recommend a healthy diet (low-fat, plant-based and low-sodium),
moderate exercise (like walking), and stopping coffee and tea (see above
article on coffee, July 2004, McDougall Newsletter).
5) If after several months (at least 3 to 6 months) of
recording blood pressures of 160/100 mmHg or greater (on average) I may
recommend drug therapy.23,24 Failure to respond to recommendation four (4)
above may be because the patient will not comply with the recommendation
to change his/her diet and exercise, or occasionally because all efforts
are still insufficient to meet the goal of a blood pressure below 160/100
mmHg (on average).
6) My drugs of choice are time-honored, inexpensive,
well-tolerated diuretics and beta-blockers.23,25 I rarely use the
high-tech, expensive medications like ACE inhibitors. I never use “calcium
channel blockers” because these drugs increase a person’s risk of death
and disease (more heart disease, cancer, bleeding, and suicide) and make
them more stupid (decrease cognitive function).26,27
7) My goal is to reduce the diastolic blood pressure to
no lower than 85 to 90 mmHg. A systolic blood pressure of about 140 mmHg
makes people happy too – however, I do not routinely lower systolic blood
pressure, regardless of the original level, with medications, if that
means also reducing the diastolic pressure below 80 mmHg – the risks are
too great for more stroke and heart attacks. (Remember, without
medications a blood pressure of 110/70 mmHg or lower is ideal.)
8) I often use other medications which lower risk
factors like cholesterol – “statins” are a class of cholesterol-lowering
medications I commonly prescribe after I have squeezed every possible
benefit from a healthy diet. My goal is to have total cholesterol below
150 mg/dl (LDL-cholesterol below 80 mg/dl). (See my June 2003 Newsletter
article: “Cleaning out Your Arteries,” at
Blood pressure is a number – George and Martha are
people. Doctors must first, last, and all the way in between, be focused
on the patient and never do harm by treating numbers at the patient’s
expense. In other words, a doctor should never brag that his patient had a
normal blood pressure from intensive drug therapy during the many months
prior to his stroke or heart attack.
*These are general guidelines that I use and I
individualize each patient’s care based on other aspects of general health
and needs. You must work with your personal physician on your health
issues, and if you are going to use this information, please do so in the
context of this very valuable doctor-patient relationship.
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of nonpharmacologic population-wide blood pressure reduction on coronary
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6) Farnett L. The J-curve phenomenon and the treatment of hypertension.
Is there a point beyond which pressure reduction is dangerous? JAMA.
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between diastolic blood pressure and myocardial infarction. Br Med J.
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electrocardiographic abnormalities: A critical analysis. Circulation.
9) Cooper S. The relation between degree of blood pressure reduction
and mortality among hypertensives in the Hypertensive Detection and
Follow-up Program. Am J Epidemiol. 127:387, 1988.
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17) Kaplan NM. What is goal blood pressure for the treatment of
Arch Intern Med. 2001 Jun 25;161(12):1480-2.
18) Voko Z. J-shaped relation between blood pressure and stroke in
treated hypertensives. Hypertension. 1999 Dec;34(6):1181-5.
19) Somes GW, Pahor M, Shorr RI, Cushman WC, Applegate WB. The role of
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20) Paran E. Blood pressure and cognitive functioning among independent
elderly. Am J Hypertens. 2003 Oct;16(10):818-26.
22) Staessen JA . Antihypertensive treatment based on blood pressure
measurement at home or in the physician's office: a randomized controlled
trial. JAMA. 2004 Feb 25;291(8):955-64.
23) Ramsay LE, Wallis EJ, Yeo WW, Jackson PR. The rationale for
differing national recommendations for the treatment of hypertension. Am J
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