Classifications of Hyperlipidemia
Hyperlipidemia means high fat and cholesterol in the blood. The amount and types of fat and cholesterol in the blood are determined by a complicated interaction of a persons genetic makeup and environmental factors such as the diet. Fats and cholesterol are generally processed in the liver and carried on proteins in the blood, forming lipoproteins, a combination of fat and protein. LDL and HDL are two types of lipoproteins, with increased LDL levels correlating with problems such as heart disease. High HDL has much fewer risks.
According to "Greenspan's Basic & Clinical Endocrinology" by Dr. David Gardner, acquired hyperlipidemia is high fat and cholesterol in the blood due to other conditions or medications. Diabetes, low thyroid hormone levels, kidney disease and some other metabolic disorders cause hyperlipidemia. Some drugs can also cause hyperlipidemia, including alcohol, diuretics, estrogens and beta blockers.
Primary Type I
Type I hyperlipidemia is quite uncommon according to "Harrison's Principles of Internal Medicine" by Anthony S Fauci. It is also called familial hyperchylomicronemia and Buerger-Gruetz syndrome. This disorder causes high chylomicrons, the proteins that carry fat from the intestine to the liver. It can cause abdominal pain, pancreatitis, fat deposits in the skin and eyes and a large liver and spleen. Treatment involves eating a healthy diet.
Primary Type II
Type II hyperlipidemia is divided into type IIa and type IIb. Type IIa is also known as familial hypercholesterolemia and type IIb is also known as familial combined hyperlipidemia. Type lIa results in high LDL, or "bad" cholesterol, levels. Type IIa also raises levels of LDL, as well as a similar lipoprotein, VLDL, which results in elevated fat levels in the blood. These conditions cause fat deposits under the skin and around the eyes, and are treated medically and with dietary control.
Primary Type III
Type III hyperlipidemia is an uncommon disorder also known as familial dysbetalipoproteinemia, remnant removal disease or broad-beta disease. It results in high levels of LDL and carries a very significant risk of heart disease. It is treated with medicine and diet.
Primary Type IV
Type IV is also known as familial hyperlipidemia. Cholesterol levels tend to be normal and fat is elevated in the blood as VLDL levels are elevated. It is also treated with medicines and proper diet.
Primary Type V
Type V is another rare type that is characterized by elevated chylomicrons and VLDL. It is also known as endogenous hypertriglyceridemia. The LDL level is typically low. High fat levels in the blood can cause pancreatitis.
- "Greenspan's Basic & Clinical Endocrinology"; David Gardner and Dolores Shoback; 8th Ed 2007
- "Harrison's Principles of Internal Medicine"; Anthony S Fauci; 17th Ed 2008
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