Familial Hypertriglyceridemia
Triglycerides are the main storage form of fat in the body and are a necessary source of energy. Familial hypertriglyceridemia is a genetic condition that causes the triglyceride levels in the blood to get too high. This relatively common condition is inherited in an autosomal dominant pattern. About 1 in 500 people in the United States has this condition.
It is important to note that many people with high triglyceride levels do not have familial hypertriglyceridemia. Some common reasons for high triglycerides include:
• Being overweight or obese
• Drinking too much alcohol
• Diabetes
• Thyroid problems
• Taking estrogen
• Eating too much fat or refined carbohydrates
• Some medications (such as Accutane)
• Kidney disease
In familial hypertriglyceridemia, a change in the genetic instructions affects the way the body handles “very low density lipoprotein” or VLDL. VLDL is made in the body by combining certain fats and proteins, including a large amount of triglyceride. VLDL is needed by to transport fats and cholesterol around the body. Once its job is complete, VLDL gets broken down by an enzyme called lipoprotein lipase. This enzyme helps breaks down triglycerides so the body can use them for energy.
There are two ways to inherit familial hypertriglyceridemia. In some families, a person inherits a tendency to make too much VLDL. In other families, a person makes the normal amount of VLDL, but due to a genetic difference, their body is unable to break down VLDL and clear it from the blood. In either situation, the level of VLDL is higher than usual, which results in a high level of triglycerides in the blood.
Why are high levels of triglycerides a risk factor for cardiovascular disease (CVD)?
The reasons why high levels of triglycerides increase the risk of CVD is not completely understood. Evidence suggests that the particles remaining in the blood after the breakdown of VLDL may lead to build up of plaque on arteries. High triglyceride levels can also increase the risk of thrombosis, or blood clotting, which can lead to a heart attack or stroke. If not treated, high triglycerides can lead to fatty liver disease. Fatty liver disease causes changes in the liver and can eventually result in permanent damage.
The level of triglycerides in the blood is related to two other lipoproteins in the body, high density lipoprotein (HDL), and small, dense, low density lipoprotein (LDL). As the ratio of triglycerides to HDL levels increases, so does the chance of having small dense LDLs. Both low levels of HDL and the presence of small dense LDLs are known risk factors for CVD. Small dense LDL can increase the risk for heart disease up to 3-fold. They are harder for the body to break down, so they stay in the blood for a longer time, where they can cause problems. Small dense LDLs are more susceptible to oxidative and structural damage and are taken up by white blood cells, know as macrophages. This leads to production of atherogenic foam cells. The foam cells trigger inflammation in the blood vessel walls, which can lead to a heart attack or stroke.
Diagnosis
A fasting triglyceride blood level of more than 100 or 150 (depending on age) indicates a possible familial hypertriglyceridemia.
Why would a doctor test triglycerides levels?
Triglyceride levels are usually part of routine choloesterol screening. They provide information about lipid levels in the body. Testing triglycerides in a person with familial hypertriglyceridemia allows the doctor to monitor the levels over time. When there are high amounts of triglycerides in the body for too long, it can cause medical problems. There is an increased risk of developing pancreatitis when triglycerides are consistently above 500. Pancreatitis is an inflammation of the pancreas that may cause severe abdominal pain. When triglycerides are continually elevated there is also a concern of developing fatty liver and xanthomas (fat deposits under the skin). Consistently high levels of triglycerides may also indicate diabetes is present or is developing.
Treatment
Lifestyle changes are the best therapy for high triglycerides. The following changes will help reduce triglycerides:
If overweight, reduce calories to lose weight. This includes all sources of calories from fats, proteins, carbohydrates and alcohol.
Do not drink alcohol. Even small amounts can lead to large changes in triglycerides.
Be physically active. Engage in some form of physical activity for at least 30 minutes a day most days of the week.
High triglycerides can happen because of too much dietary fat or carbohydrate, especially simple, or refined carbohydrate and sugar. Reduce the amount of all simple carbohydrates such as:
· Concentrated sweets (Sugar, honey, molasses, jams, jellies, and candies)
· Any food containing high fructose corn syrup (such as: some sweetened breakfast cereals, flavored yogurt, reduced fat salad dressings, and soda. Look for high fructose corn syrup on the ingredient list on the food label)
· Desserts (Pies, cakes, cookies, candy, doughnuts, ice cream frozen yogurt, and sweetened gelatin)
· Sweetened Beverages (Fruit juices, fruit drinks, fruit punches, regular sodas, carbonated pop, smoothies, sports drinks, sweetened coffee drinks, mocha, and chocolate drinks)
· Other sweetened foods (High sugar cereals, flavored yogurts, and sports or energy bars)
· Alcohol (Beer, wine, hard liquor, liqueurs)
For severely elevated triglycerides (>800), reduce fat to less than 10 grams per day and eliminate ALL simple or refined carbohydrate. Eat only small amounts of lean protein (chicken, seafood, etc) and increase foods high in soluble fiber.
People with high triglycerides may benefit from eating more fish. Include fish high in omega-3 fatty acids. Fatty fish like herring, sardines, albacore tuna and salmon are high in omega-3 fatty acids. Fish oil supplements can also be taken, if recommended by your health care provider. The therapeutic dose is 1 to 3 grams of EPA/DHA per day. Purchase fish oil capsules that have been molecularly distilled to remove contaminants. Read the label for more specifics and check with your health care provider to see if omega-3 fatty acids are right for you.
Created by: Suzanne Kordesh, MPH, RD
References: The National Lipid Association, www.lipid.org
Reviewed by: Suzanne Kordesh, MPH, RD, Kimberly Barr, MS, CGC
Last Updated: 5/11/10