What is Dyslipidemia
Dyslipidemia is an imbalance of waxy, fat-like substances (lipids) in the blood. The body needs lipids in small amounts. Dyslipidemia often involves a high level of cholesterol or triglycerides, which are types of lipids.
Defects in the production or removal of lipoproteins results in dyslipidemia. Both genetic (i.e., lipoprotein lipase deficiency, low-density lipoprotein [LDL] receptor defect) and acquired conditions (e.g., obesity, diabetes) have been implicated in the pathogenesis of lipid disorders. Dyslipidemia is characterized by total cholesterol, triglyceride (TG), or LDL level above the 90th percentile or high-density lipoprotein (HDL) level below the tenth percentile for the general population. It plays a significant role in the development of coronary heart disease. Clinical manifestations of excess LDL include atheroma, skin and tendon xanthomas, eyelid xanthelasma, and iris corneal arcus. Marked hypertriglyceridemia (> 1000 mg/dL) is associated with chylomicronemia syndrome. It is characterized by pancreatitis, eruptive skin xanthomas, and lipemia retinalis.
Common forms of dyslipidemia include:
- High levels of bad cholesterol (LDL cholesterol). LDL is the type of cholesterol that causes fatty deposits (plaques) to build up in the blood vessels that carry blood away from your heart (arteries).
- Low levels of good cholesterol (HDL cholesterol). HDL cholesterol is the type of cholesterol that protects against heart disease. High levels of HDL remove the LDL buildup from arteries.
- High levels of triglycerides. Triglycerides are a fatty substance in the blood that is linked to a buildup of plaques in the arteries.
You can develop dyslipidemia because of the genes you are born with (primary dyslipidemia) or changes that occur during your life (secondary dyslipidemia), or as a side effect of certain medical treatments.
What are the causes?
Primary dyslipidemia is caused by changes (mutations) in genes that are passed down through families (inherited). These mutations cause several types of dyslipidemia. Mutations can result in disorders that make the body produce too much LDL cholesterol or triglycerides, or not enough HDL cholesterol. These disorders may lead to heart disease, arterial disease, or stroke at an early age.
Causes of secondary dyslipidemia include certain lifestyle choices and diseases that lead to dyslipidemia, such as:
- Eating a diet that is high in animal fat.
- Not getting enough activity or exercise (having a sedentary lifestyle).
- Having diabetes, kidney disease, liver disease, or thyroid disease.
- Drinking large amounts of alcohol.
- Using certain types of drugs.
What increases the risk?
You may be at greater risk for dyslipidemia if you are an older man or if you are a woman who has gone through menopause. Other risk factors include:
- Having a family history of dyslipidemia.
- Taking certain medicines, including birth control pills, steroids, some diuretics, beta-blockers, and some medicines for HIV.
- Smoking cigarettes.
- Eating a high-fat diet.
- Drinking large amounts of alcohol.
- Having certain medical conditions such as diabetes, polycystic ovary syndrome (PCOS), pregnancy, kidney disease, liver disease, or hypothyroidism.
- Not exercising regularly.
- Being overweight or obese with too much belly fat.
What are the signs or symptoms?
Dyslipidemia does not usually cause any symptoms.
Very high lipid levels can cause fatty bumps under the skin (xanthomas) or a white or gray ring around the black center (pupil) of the eye. Very high triglyceride levels can cause inflammation of the pancreas (pancreatitis).
How is this diagnosed?
Your health care provider may diagnose dyslipidemia based on a routine blood test (fasting blood test). Because most people do not have symptoms of the condition, this blood testing (lipid profile) is done on adults age 20 and older and is repeated every 5 years. This test checks:
- Total cholesterol. This is a measure of the total amount of cholesterol in your blood, including LDL cholesterol, HDL cholesterol, and triglycerides. A healthy number is below 200.
- LDL cholesterol. The target number for LDL cholesterol is different for each person, depending on individual risk factors. For most people, a number below 100 is healthy. Ask your health care provider what your LDL cholesterol number should be.
- HDL cholesterol. An HDL level of 60 or higher is best because it helps to protect against heart disease. A number below 40 for men or below 50 for women increases the risk for heart disease.
- Triglycerides. A healthy triglyceride number is below 150.
If your lipid profile is abnormal, your health care provider may do other blood tests to get more information about your condition.
How is this treated?
Treatment depends on the type of dyslipidemia that you have and your other risk factors for heart disease and stroke. Your health care provider will have a target range for your lipid levels based on this information.
For many people, treatment starts with lifestyle changes, such as diet and exercise. Your health care provider may recommend that you:
- Get regular exercise.
- Make changes to your diet.
- Quit smoking if you smoke.
If diet changes and exercise do not help you reach your goals, your health care provider may also prescribe medicine to lower lipids. The most commonly prescribed type of medicine lowers your LDL cholesterol (statin drug). If you have a high triglyceride level, your provider may prescribe another type of drug (fibrate) or an omega-3 fish oil supplement, or both.
How and when is dyslipidemia treated?
Treatment is aimed at reducing LDL cholesterol to less than 160 mg/dL in most individuals. Lower targets are recommended in high-risk conditions like diabetes (< 100 mg/dL) and coronary heart disease (< 70 mg/dL). Target TG of less than 200 mg/dL and HDL more than 40 mg/dL is also recommended. Pharmacologic agents are recommended if target goals are not achieved with lifestyle measures. Lipid effects and potential GI side effects described in the below table.
Treatment of Dyslipidemia
|Drug Class||Mechanism of Action||HDL||TG||LDL||GI and Other Side Effects|
|Bile acid sequestrants||Binds bile acid in the intestine and enhances fecal excretion of cholesterol||↑||—||↓↓||Nausea, bloating, cramping, interferes with the absorption of other drugs|
|Fibrates||Reduces VLDL production by the liver||↑↑||↓↓↓||↓||Hepatotoxicity, cramping, nausea, myalgias|
|Nicotinic acid||Reduce free fatty acid transport to the liver and VLDL production by the liver||↑↑||↓↓||↓↓||Vomiting, diarrhea, hepatotoxicity, flushing, and pruritus|
|HMG CoA inhibitors||Inhibits HMG CoA reductase, an enzyme necessary in de novo cholesterol synthesis||↑||↓||↓↓↓||Hepatotoxicity, myositis|
|Omega 3 fatty acids||Reduces VLDL production||↑||↓||↓||Taste altered, indigestion|
|Cholesterol absorption inhibitors||Inhibits the absorption of cholesterol in the intestine||—||—||↓↓||Pancreatitis, hepatitis|
TG , triglycerides.
Follow these instructions at home:
- Take over-the-counter and prescription medicines only as told by your health care provider. This includes supplements.
regular exercise. Start an aerobic exercise and strength training program
as told by your health care provider. Ask your health care provider what
activities are safe for you. Your health care provider may recommend:
- 30 minutes of aerobic activity 4–6 days a week. Brisk walking is an example of aerobic activity.
- Strength training 2 days a week.
a healthy diet as told by your health care provider. This can help you
reach and maintain a healthy weight, lower your LDL cholesterol, and raise
your HDL cholesterol. It may help to work with a diet and nutrition
specialist (dietitian) to make a plan that is right for you. Your
dietitian or health care provider may recommend:
- Limiting your calories, if you are overweight.
- Eating more fruits, vegetables, whole grains, fish, and lean meats.
- Limiting saturated fat, transfat, and cholesterol.
- Follow instructions from your health care provider or dietitian about eating or drinking restrictions.
- Limit alcohol intake to no more than one drink per day for nonpregnant women and two drinks per day for men. One drink equals 12 oz of beer, 5 oz of wine, or 1½ oz of hard liquor.
- Do notuse any products that contain nicotine or tobacco, such as cigarettes and e-cigarettes. If you need help quitting, ask your health care provider.
Keep all follow-up visits as told by your health care provider. This is important.
Contact a health care provider if:
- You are having trouble sticking to your exercise or diet plan.
- You are struggling to quit smoking or control your use of alcohol.
- Dyslipidemia is an imbalance of waxy, fat-like substances (lipids) in the blood. The body needs lipids in small amounts. Dyslipidemia often involves a high level of cholesterol or triglycerides, which are types of lipids.
- Treatment depends on the type of dyslipidemia that you have and your other risk factors for heart disease and stroke.
- For many people, treatment starts with lifestyle changes, such as diet and exercise. Your health care provider may also prescribe medicine to lower lipids.