What Is Familial Hypercholesterolemia?
Familial hypercholesterolemia (FH) is an inherited condition that
results in high levels of total cholesterol and low-density lipoprotein (LDL)
cholesterol. Cholesterol is a waxy substance found in your cells that can be
dangerous when it builds up on artery walls. High cholesterol can cause
atherosclerosis and increase your risk of heart attacks.
As the most common form of inherited high cholesterol, FH affects
about one in
every 500 people. FH is generally more severe
than cases of non-genetic hypercholesterolemia. People who have the familial
version will generally have much higher cholesterol levels.
FH is also known as type 2 hyperlipoproteinemia.
What Are the Signs and Symptoms of Familial
High cholesterol often has no symptoms. The damage may be done
before you notice anything is wrong. Some of the signs and symptoms are:
- angina from heart disease
- xanthomas, which are fatty skin deposits on the
elbows, buttocks, knees, and tendons
- cholesterol deposits around the eyelids, which
are also known as xanthelasmas
- cholesterol deposits around the corneas, also
known as corneal arcus
Blood tests will reveal that your total and LDL cholesterol
levels are higher than normal.
What Causes Familial Hypercholesterolemia?
FH is a result of a mutated gene on chromosome 19. It’s a genetic
disorder. Unlike recessive genetic disorders that require both sides of the
family to have the condition, FH is autosomal dominant, meaning that a child
may have the condition even if only one parent has the mutated gene.
In rare instances, both parents may be carriers of the gene. When
this occurs, the condition tends to be more severe because the child may be
born with two copies of the mutated gene.
Who Is at Risk for Familial
FH is more common
among certain ethnic groups such as those of French Canadian, Finnish,
Lebanese, and South African descent. However, anyone who has a parent with the
disease is at risk.
How Is Familial Hypercholesterolemia
Your doctor will conduct a physical exam. The exam helps identify
any types of fatty deposits or lesions that have developed as a result of the
elevated lipoproteins. Your doctor will also ask about your personal and family
Your doctor will also order blood tests. The blood tests are used
to determine your cholesterol levels, and the results may indicate that you
have high levels of total cholesterol and LDL cholesterol. The results of the
test will look like the following if you do in fact have FH.
Total cholesterol will be more than:
- 250 milligrams per deciliter in children
- 300 milligrams per deciliter in adults
LDL cholesterol will be more than:
- 170-200 milligrams per deciliter in children
- 220 milligrams per deciliter in adults
Your doctor will also test your triglycerides, which are made up
of fatty acids. Triglyceride levels tend to be normal in people with this
genetic condition. Normal results are below 150 milligrams per deciliter.
Other tests may include a genetic test that establishes whether
you have the defective gene and a test for the fibroblasts, or connective
tissue cells. The test for fibroblasts can help your doctor see how cholesterol
is absorbed within your body.
How Is Familial Hypercholesterolemia
Like ordinary high cholesterol, FH is treated with diet or
medication. A combination of both is often needed to reduce cholesterol successfully
and delay the onset of heart disease or a heart attack. Your doctor will
usually ask you to modify your diet and increase exercise for several months
before suggesting medication.
If you have FH, your doctor will place you on a diet with less
than 30 percent of total calories coming from fat. You’ll be asked to:
- limit meats like lamb, beef, chicken, and pork
- restrict coconut and palm oils
- switch from full-fat dairy to low-fat or even
non-fat dairy products
Limiting or eliminating egg yolks will also contribute to
lowering your cholesterol.
Diet and exercise are important to maintaining a healthy weight,
which can help lower cholesterol levels.
You may need medications to reduce your cholesterol if lifestyle
modifications do not work.
Statins are the most common drugs used to reduce LDL cholesterol.
Examples of statins include:
Other drugs that lower cholesterol include:
- bile acid-sequestering resins
- nicotinic acid
What Are the Complications of FH?
Possible complications of FH include:
- a heart attack at an early age
- heart disease
- a stroke
What Is the Long-Term Outlook for FH?
The outcome depends on whether or not you make lifestyle
modifications and take your prescribed medications. These changes can significantly
delay a heart attack.
People who inherit the mutated gene from both parents are at
greater risk for heart attack and death before age 30. Men with FH tend to have
heart attacks when they’re in their 40s or 50s. Eighty-five percent of men with this
condition have a heart attack by the time they reach 60. Women with this
condition tend to have heart attacks in their 50s or 60s.
Can I Prevent Familial Hypercholesterolemia?
Because FH is genetic, the best way to prevent it is to seek
genetic counseling before conceiving. A genetic counselor will be able to test
you and your partner for the mutated gene. If you already have the disease, the
key to living longer is to control your cholesterol levels.