Hyperlipoproteinemia

What is Hyperlipoproteinemia ?

Hyperlipoproteinemia-marked by increased plasma concentrations of one or more lipoproteins-affects lipid transport in serum. Primary hyperlipoproreinemia includes at least five distinct metabolic disorders, all of which may be inherited. Hyperlipoproteinemia also occurs secondary to other conditions such as diabetes mellitus.

Causes of Hyperlipoproteinemia

The primary hyperlipoproteinemias result from genetic disorders. Types I and III are transmitted as autosomal recessive traits; types II, IV, and V are transmitted as autosomal dominant traits. Secondary hyperlipoproteinemia results from another metabolic disorder, such as diabetes mellitus, pancreatitis, hypothyroidism, or renal disease.

Signs & Symptoms of Hyperlipoproteinemia

Patients experience the following symptoms:

• Main health issues with any cholesterol problem is that there are often no obvious symptoms of the condition before the development of coronary artery disease.

Because of the very high cholesterol levels, many people with this disease develop cholesterol deposits in the skin. These are often seen on the:

• knuckles of the hand
• elbows
• Achilles tendons
• eyelids

Diagnostic Tests

Serum lipid profiles - elevated levels of total cholesterol, triglycerides, very-low-density lipoproteins (VLDLs), low-density lipoproteins (LDLs), or high­ density lipoproteins (HDLs) indicate hyperlipoproteinemia.

Treatment

Primary treatment is focused on dietary management, including weight reduction, restriction of cholesterol and saturated animal fat intake, and inclusion of polyunsaturated vegetable oils, which reduce concentration of plasma LDL. Dietary fat should account for no more than 30% of the total caloric intake.

The second therapeutic aim is to eliminate aggravating factors, such as diabetes mellitus, alcoholism, and hypothyroidism. The patient should also reduce other risk factors that may predispose him to atherosclerosis. Self-care measures may include cessation of smoking, treatment of hypertension, maintenance of a good exercise and physical fitness program and, if the patient has diabetes mellitus, control of blood glucose levels.

Treatment may be supplemented by drug therapy (cholestyramine, clofibrate, colestipol hydrochloride, gemfibrozil, lovastatin, nicotinic acid, pravastatin sodium. probucol. or simvastatin) to lower plasma concentrations of lipoproteins. either by decreasing their production or by increasing their removal from plasma.

Type I hyperlipoproteinemia requires long-term weight reduction. with fat intake restricted to less than 20 g/day. A 20- to 40-g/day,medium-chain triglyceride diet may be ordered to supplement caloric intake. The patient should also avoid alcoholic beverages to derease plasma triglyceride levels. The prognosis is good with treatment; without treatment, death can result from pancreatitis.

For type II hyperlipoproteinemia, dietary mancgemem to restore normal lipid levels and decrease the risk of atherosclerosis includes restriction of cholesterol intake to less than 300 mg/day for adults and less than 150 mg/day for children. Additional measures include restricting triglyceride intake to less than 100 mg/day for children and adults. The diet should be high in polyunsaturated fats.

In familial hypercholesterolemia, nicotinic acid with a bile acid usually normalizes LDL levels.

If the patient can't tolerate drug therapy, surgical creation of an ileal bypass may be necessary. This surgery accelerates the loss of bile acids in the stool and often causes heterozygotes to show a moderate to marked reduction of plasma cholesterol levels.

For severely affected homozygote children, portacaval shunt may be used as a last resort to reduce plasma cholesterol levels. Prognosis remains poor regardless of treatment in homozygotes; myocardial infarction usually causes death before age 30.

For type III hyperlipoproteinemia, dietary management includes restriction of cholesterol intake to less man 300 mg/day; carbohydrates must also be restricted, and polyunsaturated fats are increased. Clofibrate and niacin help lower blood lipid levels. Weight reduction is helpful. With strict adherence to the prescribed diet, the prognosis is good.

For type IV hyperlipoproteinemia, weight reduction may normalize blood lipid levels without additional treatment. Long-term dietary management includes restricted cholesterol intake, increased polyunsaturted fats, and avoidance of alcoholic beverages. Some patients respond to drug therapy; for example, gefibrozil or nicotinic acid. Clofibrate and niacin ,may be helpful in treating certain patients. The prognosis remains uncertain. however. because of predisposition to premature coronary artery disease (CAD).

The most effective treatment for type V hyperlipoproteinemia is weight reduction and long-term maintainenance of a low-fat diet. Alcoholic beverages and oral contraceptives must be avoided. Niacin, clofibrate, gemfibrozil, and a 20- to 40-g/day medium-chain triglyceride diet may be helpful. The prognosis is uncertain because of the risk of pancreatitis. Increased fat intake can cause recurrent bouts of illness. possibly leading to pseudocyst formation, hemorrhage, and death.

Prevention Tips

Prevention of early heart attacks requires recognition of existing elevated LDL levels, and a low-cholesterol, low-saturated fat, high-unsaturated fat diet in high-risk people may help to control LDL levels.