Table of Contents
What is Hyperlipidemia and Definition
Hyperlipidemia is a disorder of lipid METABOLISM, also called hyperlipoproteinemia, that results in abnormally high levels of cholesterol, triglycerides, and lipoproteins in the BLOOD circulation. Hyperlipidemia is a key contributor to ATHEROSCLEROSIS, CORONARY ARTERY DISEASE (CAD), and PERIPHERAL VASCULAR DISEASE (PVD). Hyperlipidemia also can cause health conditions such as PANCREATITIS. Some forms of hyperlipidemia are familial or hereditary and may manifest regardless of lifestyle.
Medications can cause hyperlipidemia as well, notably oral contraceptives (birth control pills), estrogen therapy, thiazide diuretics, and corticosteroids. Hyperlipidemia may also be a sign of other health conditions such as CUSHING’S SYNDROME, DIABETES, LIVER dysfunction, and SYSTEMIC LUPUS ERYTHEMATOSUS (SLE). In most people who have hyperlipidemia, however, it appears that lifestyle factors interact with genetics.
Doctors measure lipid levels in the blood and consider them individually as well as in correlation to each other in determining the extent of cardiovascular risk they pose. There are five types, or classifications, of hyperlipidemia that have unique presentations, genetic factors, and characteristic progressions. The five types of hyperlipidemia are
- type I, a rare inherited lipid disorder sometimes called apolipoprotein C-II deficiency, in which very low density lipoprotein (VLDL) triglycerides and lipids called chylomicrons accumulate in the bloodstream
- type II, a common group of familial or acquired lipid disorders, sometimes called hypercholesterolemia, in which low-density lipoprotein (LDL) cholesterol levels in the blood are elevated, and there may be apolipoprotein B deficiency
- type III, an uncommon familial lipid disorder in which VLDL and total cholesterol are elevated, usually resulting from apolipoprotein E deficiency
- type IV, a common familial or acquired lipid disorder in which blood lipid elevations are associated with OBESITY and decline with weight loss
- type V, an uncommon lipid disorder in which triglycerides are extremely elevated, though other blood lipid levels are fairly normal, and that frequently causes pancreatitis
Most forms of hyperlipidemia can occur without evidence of familial or hereditary connections.
Symptoms of Hyperlipidemia and Diagnostic Path
Hyperlipidemia itself does not cause symptoms. Doctors detect hyperlipidemia through blood tests, conducted after an 8- to 12-hour fast, that measure blood lipid levels. The pretest fast is important to remove any dietary influences. Elevated blood lipid levels are diagnostic. When blood lipid levels are extremely high and other risks for CARDIOVASCULAR DISEASE (CVD) exist, the doctor may recommend further evaluation to look for CAD, PVD, and other atherosclerotic conditions.
Hyperlipidemia Treatment Options and Outlook
Regardless of the cause of elevated blood lipids, the important therapeutic goal is to reduce them. For people who have mild to moderate elevations and no other cardiovascular disease risk factors (including family history of hyperlipidemia), lifestyle changes alone may be enough to bring lipid levels down to acceptable ranges. Doctors are generally willing to give this approach about two months to lower blood lipid levels. When lipid levels remain elevated despite lifestyle changes, or the person cannot make adequate lifestyle changes, health experts recommend lipid-lowering medications. Lowering blood lipids results in a significant decrease in cardiovascular risk, especially for early CAD and HEART ATTACK (before age 40).
Medications to treat Hyperlipidemia
|MEDICATIONS TO TREAT HYPERLIPIDEMIA|
|Bile acid sequestrants|
|Selective cholesterol absorption inhibitors|
Many doctors recommend niacin, either alone or in combination with lipid-lowering medications, to help lower blood lipid levels. Niacin decreases the liver’s production of VLDL and lowdensity lipoprotein (LDL), which curtails triglyceride production. Niacin can cause unpleasant facial flushing and tingling sensations in the fingers and toes, however, even at low doses.
Risk Factors and Preventive Measures
The key risk factors for hyperlipidemia are family history and lifestyle habits. Most people can lower their risk for hyperlipidemia through eating habits and exercise. Even in combination with medication, lifestyle factors are important for maintaining healthy lipid metabolism.