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Please
be aware that the information given in these
articles, features and Q and A should in no
way be taken as a substitute for professional
advice. If you have questions or concerns
regarding your, your family's or your child's
physical or mental health, please seek
professional assistance.
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What
Is Coronary Heart
Disease?
Heart
disease is caused by
narrowing of the
coronary arteries that
feed the heart. Like any
muscle, the heart needs
a constant supply of
oxygen and nutrients,
which are carried to it
by the blood in the
coronary arteries. When
the coronary arteries
become narrowed or
clogged by cholesterol
and fat deposits--a
process called
atherosclerosis--and
cannot supply enough
blood to the heart, the
result is coronary heart
disease (CHD). If not
enough oxygen-carrying
blood reaches the heart,
you may experience chest
pain called angina. If
the blood supply to a
portion of the heart is
completely cut off by
total blockage of a
coronary artery, the
result is a heart
attack. This is usually
due to a sudden closure
from a blood clot
forming on top of a
previous narrowing.
Cholesterol
is a waxy, fat-like
substance that occurs
naturally in all parts
of the body and that
your body needs to
function normally. It is
present in cell walls or
membranes everywhere in
the body, including the
brain, nerves, muscle,
skin, liver, intestines,
and heart. Your body
uses cholesterol to
produce many hormones,
vitamin D, and the bile
acids that help to
digest fat. It takes
only a small amount of
cholesterol in the blood
to meet these needs. If
you have too much
cholesterol in your
bloodstream, the excess
is deposited in
arteries, including the
coronary arteries, where
it contributes to the
narrowing and blockages
that cause the signs and
symptoms of heart
disease.
What
does cholesterol have to
do with heart disease?
The
Framingham Heart Study
established that high
blood cholesterol is a
risk factor for coronary
heart disease (CHD).
Results of the
Framingham study showed
that the higher the
cholesterol level, the
greater the CHD risk. On
the other end of the
spectrum, CHD is
uncommon at total
cholesterol levels below
150 milligrams per
deciliter (mg/dL). A
direct link between high
blood cholesterol and
CHD has been confirmed
by the Lipid Research
Clinics-Coronary Primary
Prevention Trial (1984)
which showed that
lowering total and LDL
("bad")
cholesterol levels
significantly reduces
CHD. A series of more
recent trials of
cholesterol lowering
using statin drugs have
demonstrated
conclusively that
lowering total
cholesterol and LDL-cholesterol
reduces the chance of
having a heart attack,
needing bypass surgery
or angioplasty, and
dying of CHD-related
causes.
Click
on any of the links
below for more specific
information.
In
addition to high
cholesterol, there are
other risk factors that
can increase your chance
of developing heart
disease. To learn more
about risk factors,
click below.
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What
Makes Your
Cholesterol
High or Low?
Your
blood cholesterol
level is affected
not only by what
you eat but also
by how quickly
your body makes
LDL
("bad")
cholesterol and
disposes of it. In
fact, your body
makes all the
cholesterol it
needs, and it is
not necessary to
take in any
additional
cholesterol from
the foods you eat.
Many
factors help
determine whether
your LDL-cholesterol
level is high or
low. The following
factors are the
most important:
Heredity.
Your genes
influence how high
your LDL
("bad")
cholesterol is by
affecting how fast
LDL is made and
removed from the
blood. One
specific form of
inherited high
cholesterol that
affects 1 in 500
people is familial
hypercholesterolemia,
which often leads
to early heart
disease. But even
if you do not have
a specific genetic
form of high
cholesterol, genes
play a role in
influencing your
LDL-cholesterol
level.
What
you eat. Two main
nutrients in the
foods you eat make
your LDL
("bad")
cholesterol level
go up: saturated
fat, a type of fat
found mostly in
foods that come
from animals; and
cholesterol, which
comes only from
animal products.
Saturated fat
raises your LDL-cholesterol
level more than
anything else in
the diet. Eating
too much saturated
fat and
cholesterol is the
main reason for
high levels of
cholesterol and a
high rate of heart
attacks in the
United States.
Reducing the
amount of
saturated fat and
cholesterol you
eat is a very
important step in
reducing your
blood cholesterol
levels.
Weight.
Excess weight
tends to increase
your LDL
("bad")
cholesterol level.
If you are
overweight and
have a high LDL-cholesterol
level, losing
weight may help
you lower it.
Weight loss also
helps to lower
triglycerides and
raise HDL
("good")
cholesterol
levels.
Physical
activity/exercise.
Regular physical
activity may lower
LDL
("bad")
cholesterol and
raise HDL
("good")
cholesterol
levels.
Age
and sex. Before
the age of
menopause, women
usually have total
cholesterol levels
that are lower
than those of men
the same age. As
women and men get
older, their blood
cholesterol levels
rise until about
60 to 65 years of
age. After the age
of about 50, women
often have higher
total cholesterol
levels than men of
the same age.
Alcohol.
Alcohol intake
increases HDL
("good")
cholesterol but
does not lower LDL
("bad")
cholesterol.
Doctors don't know
for certain
whether alcohol
also reduces the
risk of heart
disease. Drinking
too much alcohol
can damage the
liver and heart
muscle, lead to
high blood
pressure, and
raise
triglycerides.
Because of the
risks, alcoholic
beverages should
not be used as a
way to prevent
heart disease. |
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| Stress.
Stress over the
long term has been
shown in several
studies to raise
blood cholesterol
levels. One way
that stress may do
this is by
affecting your
habits. For
example, when some
people are under
stress, they
console themselves
by eating fatty
foods. The
saturated fat and
cholesterol in
these foods
contribute to
higher levels of
blood cholesterol. |
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The
Benefits of Cholesterol
Lowering
Recent
studies have shown that
cholesterol lowering in
people without heart
disease greatly reduces
their risk for
developing CHD,
including heart attacks
and CHD-related death.
This is true for those
with high cholesterol
levels and for those
with average cholesterol
levels.
A
1995 study called the
West of Scotland
Coronary Prevention
Study (WOSCOPS) found
that cholesterol
lowering reduced the
number of heart attacks
and deaths from
cardiovascular causes in
men with high blood
cholesterol levels who
had not had a heart
attack. For 5 years,
more than 6500 men with
total cholesterol levels
of 249 milligrams per
deciliter (mg/dL) to 295
mg/dL were given either
a cholesterol-lowering
drug or a placebo (a
dummy pill that looks
exactly like the
medication), along with
a cholesterol lowering
diet. The drug that was
given is known as a
statin (pravastatin),
and it reduced total
cholesterol levels by 20
percent and LDL
("bad")
cholesterol levels by 26
percent. The study found
that in those receiving
the statin, the overall
risk of having a
nonfatal heart attack or
dying from CHD was
reduced by 31 percent.
The need for bypass
surgery or angioplasty
was reduced by 37
percent and deaths from
all cardiovascular
causes by 32 percent. A
very important finding
is that deaths from
causes other than
cardiovascular disease
were not increased, and
the overall deaths from
all causes were reduced
by 22 percent.
In
1998, the results of the
Air Force/Texas Coronary
Atherosclerosis
Prevention Study (AFCAPS/TexCAPS)
showed that cholesterol
lowering in generally
healthy people with
average cholesterol
levels reduced their
risk for a first-time
major coronary event by
37 percent. Study
participants had no
obvious evidence of CHD
and relatively usual
total cholesterol levels
(average of 221 mg/dL)
and LDL-cholesterol
levels (average of 150
mg/dL) and lower than
usual HDL
("good")
cholesterol levels
(average of 36 mg/dL for
men and 40 mg/dL for
women). This study used
a statin drug (lovastatin)
along with a
low-saturated fat,
low-cholesterol diet to
lower cholesterol
levels. Study
participants who
received a placebo
followed the same
low-saturated fat,
low-cholesterol diet.
After one year, total
cholesterol levels in
the treatment group were
lowered by 18 percent
and LDL-cholesterol
levels by 25 percent.
The risk for a heart
attack was reduced 40
percent, unstable angina
32 percent, the need for
bypass surgery or
angioplasty 33 percent,
and cardiovascular
events 25 percent. The
cholesterol-lowering
benefits in this study
extended to both men and
women as well as older
adults. There were no
significant differences
between treatment and
placebo groups in
non-cardiovascular
disease deaths.
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Risk
Factors and Heart
Disease
Risk
factors are conditions
that increase your risk
for developing heart
disease. Some risk
factors can be changed
and others cannot. In
general, the more risk
factors you have, the
greater your chance of
developing heart
disease. Fortunately,
there are things you can
do to address most of
the risk factors for
heart disease.
The
risk factors that you cannot
control include:
- Age
(45 years or older
for men; 55 years or
older for women)
- Family
history of early
heart disease
(father or brother
affected before age
55; mother or sister
affected before age
65)
The
known risk factors for
heart disease that you can
do something about
include:
- High
blood cholesterol
(high total
cholesterol and high
LDL
("bad")
cholesterol)
- Low
HDL
("good")
cholesterol
- Smoking
- High
blood pressure
- Diabetes
-- if you have
diabetes, your risk
for developing heart
disease is high, as
high as a heart
disease patient's
risk for having a
heart attack. You
will need to lower
your cholesterol
under medical
supervision, in much
the same way as a
heart disease
patient, in order to
reduce your high
risk of getting
heart disease.
- Obesity/overweight
- Physical
inactivity
If
you have not had your
cholesterol level
checked, talk to your
doctor about getting it
checked.
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