High
Blood Pressure Puts Many US Adults At Risk
May Is National
High Blood Pressure Education Month
Health experts call
it "prehypertension," and it points to a reason why more US
adults than ever before should be concerned about high
blood pressure.
People with prehypertension
have blood pressure ranging from 120/80 to 139/89, readings
previously considered to be the high end of normal.
"We expanded the limits
based on long-standing evidence that blood pressures above 115
or 120 carry a higher risk of cardiovascular disease," says
Dr. Dan Jones, dean of the University of Mississippi School
of Medicine and a member of the government-sponsored board that
redrafted the guidelines for hypertension in 2003.
Learning
More about High Blood Pressure
And with May designated
National High Blood Pressure Education Month,
health experts hope to focus attention on prehypertension and
high blood pressure, and offer information on prevention and
management.
About 45 million Americans
who previously thought they had normal blood pressure are considered
to have prehypertension. That is in addition to the 60
million people who have full-blown high blood pressure.
High blood pressure
increases the risk of coronary heart disease. Left untreated,
it can cause heart attack and stroke - the first and third leading
causes of death, respectively, among US men and women.
High blood pressure
can even occur in children, but it is more common among
people over age 35, according to the American Heart
Association (AHA).
It is particularly
prevalent among African Americans; middle-aged and elderly people;
the obese; heavy drinkers; and women taking birth control pills.
People with diabetes, gout, or kidney disease also are more
likely to develop high blood pressure.
It is impossible
to know without testing if a person has high blood pressure
because the condition has no symptoms. One in four adult Americans
has high blood pressure, and nearly a third of them do not know
it, the AHA says.
Prehypertension was identified
as a risk in guidelines because physicians found people's bodies
were suffering damage from their elevated blood pressure, although
not as much as if they had true hypertension.
"There were certain
patients at high risk," says Dr. Ernesto Schiffrin, a professor
of medicine at the University of Montreal. "Diabetics and people
with chronic renal failure had to be treated at lower blood
pressure levels than earlier recommended."
Dr. Jones says people
with elevated, but not high, blood pressure had been told in
the past that they were suffering from "high-normal" blood pressure,
a diagnosis that did not indicate the seriousness of the situation.
"That term was not
getting the attention of the public or of clinicians," he says.
"We are more keenly aware that it's not healthy to have blood
pressure in that range. This was simply a change in nomenclature
to make people more aware of the risks we already knew about."
Focus
on Prevention Takes Center Stage
The revised guidelines
recommend that people suffering from prehypertension make lifestyle
changes to treat the condition. These include controlling their
weight, taking part in regular physical exercise, and moderating
their intake of salt and alcohol.
People with prehypertension
also are encouraged to take part in the so-called DASH (Dietary
Approaches to Stop Hypertension) diet, which emphasizes fruits,
vegetables, and low-fat dairy products. It has been proven to
lower blood pressure.
Another element of
the new guidelines involves medications for people with full-fledged
high blood pressure. Physicians are now encouraged to emphasize
the use of diuretics, which help rid the body of excess fluids
and salt, to treat hypertension, Dr. Jones says.
"The recommendation
was for clinicians to choose between a group of medications,
but that preference should be given to diuretics for people
who don't have a special reason to take another type of medication,"
Dr. Jones says.
Diuretics are proven
to work well against high blood pressure, but in the past there
was concern that side effects such as low potassium and elevated
blood sugar made them less safe for some patients.
"While those side
effects are there in some patients, recent evidence clearly
indicates that diuretics are equal or superior to other types
of blood pressure medication," Dr. Jones says. "Diuretics also
are inexpensive, and part of this is cost-effectiveness."
The guidelines also
recommend using a combination of medications to treat high blood
pressure, especially when the condition is first diagnosed,
Dr. Schiffrin says.
"The diuretics should
be given priority," Dr. Schiffrin says. "It was considered that
all hypertensives should have a diuretic as part of their medicinal
cocktail. But it was found that many patients require more than
one agent."
Most clinical trials
have found that between two to four medicines working in concert
have helped people lower their blood pressure, he says.
Some well-established
therapies include beta blockers, which reduce the heart rate
and its output of blood. Other beneficial drugs are ACE (angiotensin
converting enzyme) inhibitors, angiotensin II receptor blockers
and calcium channel blockers, the AHA states.
ACE inhibitors interfere
with the body's production of angiotensin, a chemical that causes
arteries to constrict. Angiotensin II receptor blockers thwart
the effects of angiotensin. And calcium channel blockers can
cut the heart rate and relax blood vessels.
Always consult your
physician for more information.
Online
Resources
(Our Organization
is not responsible for the content of Internet sites.)
American
Heart Association
Centers
for Disease Control and Prevention (CDC)
Guide
to Lowering Blood Pressure (NHLBI)
HealthierUS.Gov
National
Heart, Lung, and Blood Institute (NHLBI)
National
Institutes of Health (NIH)
National
Library of Medicine
The
Heart Truth National Awareness Campaign
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May 2004
High
Blood Pressure Puts Many US Adults At Risk
Focus
on Prevention Takes Center Stage
Blood
Pressure FAQ
Risk
Factors for High Blood Pressure
Online
Resources
Blood
Pressure FAQ
Blood pressure, measured
with a blood pressure cuff and stethoscope by a nurse or other
healthcare provider, is the force of the blood pushing against
the artery walls.
Each time the heart
beats, it pumps blood into the arteries, resulting in the highest
blood pressure as the heart contracts.
One cannot take his/her
own blood pressure unless an electronic blood pressure monitoring
device is used. Electronic blood pressure monitors may also
measure the heart rate, or pulse.
Two numbers are recorded
when measuring blood pressure. The higher number, or systolic
pressure, refers to the pressure inside the artery when the
heart contracts and pumps blood through the body.
The lower number,
or diastolic pressure, refers to the pressure inside the artery
when the heart is at rest and is filling with blood.
Both the systolic
and diastolic pressures are recorded as "mm Hg" (millimeters
of mercury). This recording represents how high the mercury
column is raised by the pressure of the blood.
High blood pressure,
or hypertension, directly increases the risk of coronary heart
disease (heart attack) and stroke (brain attack). With high
blood pressure, the arteries may have an increased resistance
against the flow of blood, causing the heart to pump harder
to circulate the blood.
According to the National
Heart, Lung, and Blood Institute (NHLBI), high blood
pressure for adults is defined as:
140 mm Hg or greater
systolic pressure and
90 mm Hg or greater diastolic pressure
In an update of NHLBI
guidelines for hypertension in 2003, a new blood pressure category
was added called prehypertension:
120 mm Hg –
139 mm Hg systolic pressure and
80 mm Hg – 89 mm Hg diastolic pressure
The new NHLBI
guidelines now define normal blood pressure as follows:
Less than 120
mm Hg systolic pressure and less than 80 mm Hg diastolic pressure
These numbers should
be used as a guide only. A single elevated blood pressure measurement
is not necessarily an indication of a problem.
A physician will
want to see multiple blood pressure measurements over several
days or weeks before making a diagnosis of hypertension (high
blood pressure) and initiating treatment.
A person who normally
runs a lower-than-usual blood pressure may be considered hypertensive
with lower blood pressure measurements than 140/90.
Always consult your
physician for more information.
Risk
Factors for High Blood Pressure
High blood pressure
can occur in anyone, but is particularly prevalent in:
-
persons with diabetes mellitus,
gout, or kidney disease
-
African-Americans (particularly
those who live in the southeastern United States)
-
persons in their early to
middle adult years; men in this age group have higher
blood pressure more often than women in this age group
-
persons in their middle to
later adult years; women in this age group have higher
blood pressure more often than men in this age group (more
women have high blood pressure after menopause than men
of the same age)
-
middle-aged and elderly people
- more than half of all Americans age 65 and older have
high blood pressure
-
persons whose parents or
grandparents have/had high blood pressure.
obese people
-
heavy drinkers of alcohol.
women who are taking oral contraceptives
Always consult your
physician for more information.
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