What is Hyperlipoproteinemia?

Hyperlipoproteinemia, also known as familial hyperlipoproteinemia, is metabolic disorder that results in elevated amounts of lipoproteins in the blood. It is a genetic disorder usually seen in older individuals, but it can also occur in children and younger adults. Lipoproteins are compounds in the body containing proteins and lipids, or fats, that transport cholesterol and triglycerides through the bloodstream. Examples of lipoproteins are low density lipoprotein (LDL), high density lipoprotein (HDL), chylomicron, intermediate density lipoprotein (IDL), and very low density lipoprotein (VLDL).

There are five forms of hyperlipoproteinemia. The severity of the disorder usually depends on the type and kind of lipoprotein being elevated. A common symptom of hyperlipoproteinemia is the development of xanthelasma, or the presence of fat deposits in the upper eyelids. Atherosclerosis, the hardening and narrowing of blood vessels due to fat or lipid deposition on vessel walls, can also occur. If not treated early, the disorder can lead to a heart attack or stroke.

The first type of hyperlipoproteinemia is known as familial hyperchylomicronemia syndrome. It is often characterized by the predominant elevation of chylomicrons in the blood. Chylomicrons are transport vehicles for cholesterol and triglycerides in the small intestines toward other tissues in the body. Type II is called hypercholesterolemia and is mainly seen in patients with high levels of cholesterol and LDLs in the blood. LDLs are also called the bad cholesterol, as they often indicate the presence of heart problems, such as high blood pressure or hypertension.

Hyperlipoproteinemia type III presents with high chylomicron concentrations as well as high amounts of IDLs in the blood. IDLs are formed from the breakdown of LDL in circulation. Type IV is called hyperglyceridemia, and indicates high triglyceride levels in the blood, while type V is characterized by high concentrations of VLDLs. VLDLs are lipoproteins which are converted into LDLs in the circulation. Acquired forms of hyperlipoproteinemia are frequently due to hypothyroidism, uncontrolled diabetes mellitus, kidney problems and pancreatitis.

A lipid profile test, which measures the amount of total cholesterol, triglycerides, HDL and LDL in the blood, is often needed for the diagnosis of hyperlipoproteinemia. Cardiologists, doctors who specialize in heart and blood vessel problems, usually treat the disease with medications known to lower lipoprotein, cholesterol and triglyceride levels in the body. They also often advise patients to reduce weight, stop smoking, follow a healthy low-fat diet, and have a regular exercise regimen. These are often necessary measures to prevent further complications.