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.
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.
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.
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.
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 medical history.
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.
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:
- simvastatin (Zocor)
- lovastatin (Mevacor, Altoprev)
- atorvastatin (Lipitor)
- fluvastatin (Lescol)
- rosuvastatin (Crestor)
Other drugs that lower cholesterol include:
- bile acid-sequestering resins
- nicotinic acid
Possible complications of FH include:
- a heart attack at an early age
- heart disease
- a stroke
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.
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.