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Hyperlipidemia Introduction |
The term
hyperlipidemia signifies high
lipid or fat content in the blood. Most people are familiar with having
high cholesterol, but
hyperlipidemia could also refer to
having high amounts of
triglycerides, phospholipids, or
other fats in the bloodstream.
Hyperlipidemia may be caused by
genetic factors, as in certain
familial diseases. It may also
be caused by secondary
factors like certain dietary
influences, especially in acquired
hyperlipidemia.
It is important to consider what
the health implications of hyperlipidemia are,
and separate out
what causes high levels of fat to be
harmful. Individuals at at
increased risk of development must
understand both the
necessity ,and appropriate types and amounts
of dietary fats.
Cholesterol is a
critical molecule. We get
cholesterol from endogenous sources,
meaning that we produce it. We
also derive cholesterol from those exogenous sources
food we eat, namely, meat, poultry,
eggs and dairy products. It is
important to note that cholesterol
only comes from foods made from
animals. Produced in the liver, it
provides for many critical roles in
human physiology. Cholesterol
is considered the starting
building block for our hormones,
assists in the formation of integral cellular membranes,
and is one of the main substances
that the brain is made from.
Therefore, we need the right amounts
of this substance to maintain
optimal function.
Because cholesterol
and other fats can't dissolve in the
blood, special carriers known as
lipoproteins transport the fats
between cells. These carriers are known as chylomicrons,
and include; low-density
lipoproteins (LDL),
intermediate-density
lipoproteins (IDL),
high-density lipoproteins
(HDL), and very
low-density lipoproteins VLDL. [1] Of most clinical importance are the
low-density, and high-density lipoproteins, or
LDLs and HDLs.. LDLs are also known as the "bad" cholesterol
and high-density lipoproteins, or
HDLs, are known as the "good"
type of cholesterol.
-
LDL cholesterol
is responsible for transporting
fats form the liver to body cells.
In excess they can accumulate in
the arteries, increasing the risk
of heart attack and stroke.
-
HDL cholesterol
on the other hand, carries
cholesterol back to the liver and
is shown to be protective against
the abovementioned diseases.
It should be
understood that cholesterol in
isolation isn't the
problem. Cholesterol becomes
problematic when it becomes oxidized
by free radicals, often leading to a
cascade of events that eventuates in
plaques in the arteries.
Triglycerides are the
most common dietary fats, and are
the main component of vegetable oil
and animal fat. They are comprised
of fatty acids with an esterified
glycerol backbone, and are essential
for producing some of the energy
that our cells depend on for their
functioning. During the digestive
process, triglycerides are split
into specialized components, travel to the
blood stream where they are
reassembled into constituents of
lipoproteins. Various tissues store
these packages, which are broken
down as necessary for energy
production.
A high level of
triglycerides in the blood is known
as hypertriglyceridemia, a subset of
hyperlipidemia. The health
implications of this state are
related to an increased risk of
atherosclerosis (hardening of the
arteries), and by extension, heart
disease, and stroke. In addition,
there is a strong inverse
relationship between high
triglycerides
and low HDL. the condition of high
triglycerides is often paralleled by low
HDL, setting one up for
negative health consequences.
Other markers related
to increased risk of heart disease
and strokes are the apolipoprotein
A1 (Apo A1) and B (Apo B). Apolipoproteins are a combination of
lipid and protein that function with
the lipoproteins. Specifically, Apo
A1 is primarily found in HDL
cholesterol, while Apo B makes up
a large percent of LDL
cholesterol. Subsequently, their
ratio is a convenient marker for
assessing atherosclerotic risk.
Other markers such as lipoprotein A,
C-Reactive Protein (CRP), the
amino acid homocysteine, along with
diet, lifestyle, age, family,
history health history, all
contribute to a comprehensive
assessment of one's cardiovascular risk.
Symptoms of
hyperlipidemia don't really
exist. Unfortunately, if not
detected early, the end result of
high levels of fat in the blood could
be heart disease, stroke, pancreatitis, or other chronic
diseases. What's even more alarming
is that the first
signs of these diseases are of the
event itself, such as a heart
attack or stroke. Fortunately,
prevention of these conditions can
be achieved by regular lab testing
to determine levels of cholesterol
and triglycerides as well as other
risk factors. Assessment of
one's risk enables at risk
individuals to seek
treatment and ward off further
complications, and to engage in
preventative measures to avoid the
more serious consequences. Conditions that
increase risk for hyperlipidemia
include;
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Diabetes Mellitus
(non-insulin dependent and insulin
dependent)
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Hypothyroidism
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Cushing's Syndrome
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Obesity
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Certain types of
renal (kidney) disease
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Diet high in
saturated fat (fried foods)
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Sedentary lifestyle
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Cigarette smoking
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Excessive alcohol
consumption
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Medications such as
beta blockers, diuretics and birth
control pills
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Hyperlipidemia Statistics |
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The percent of
adults age 20 years and older with
high serum levels of
cholesterol was 17% of the
population (based on the years
1999 to 2002).
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The average serum
cholesterol level for
adults' age 20 years and over: 203
mg/dL (1999-2002).
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Percent of visits
to office-based physicians with
cholesterol measure ordered or
provided: 5.2 (2002) [2].
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Approximately 105
million American adults have total
blood cholesterol levels of 200
milligrams per deciliter (mg/dL)
and higher. Of these, 42 million
have levels of 240 mg/dL or
higher, which is considered high
risk. [3]
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Learn More About
Hyperlipidemia |
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