High Cholesterol

Alternate Names
hypercholesterolemia

Definition of High Cholesterol

High cholesterol is an excessive level of cholesterol in the blood. Cholesterol is a type of lipid, or fat, that is used as a building block for hormones and for other body processes. Low-density lipoprotein, or LDL, is known as the "bad cholesterol" or "lethal cholesterol". High-density lipoprotein, or HDL, is known as the "good cholesterol" or "healthy cholesterol..

What is going on in the body?

The body produces all the cholesterol it needs. When too much cholesterol and other fats are consumed/produced, the body cannot get rid of the excess. The fats build up in various cells and tissues of the body. Cholesterol can build up on the insides of blood vessel walls. This results in atherosclerosis, or hardening of the arteries.

LDL cholesterol is the main source of build-up on the blood vessel walls. HDL cholesterol carries cholesterol back to the liver and prevents build-up on the blood vessel walls.

What are the signs and symptoms of the disease?

A high total cholesterol or high LDL level in the blood causes no symptoms in and of itself. Instead, symptoms occur when cholesterol builds up in a part of the body that is vulnerable. For example, atherosclerosis of the arteries that supply the heart causes coronary artery disease (CAD). The individual may then have chest pain and shortness of breath.

What are the causes and risks of the disease?

Common causes of high cholesterol include the following:

• heredity
• diet high in cholesterol and saturated fat
• excess weight
• lack of physical activity and exercise
• smoking

Until age 45, men tend to have higher total cholesterol levels than women do, and women tend to have higher HDL levels. This is part of the reason shy men in their 40s are four times more likely to die from heart disease than are women the same age.

However, as women age, their risk increases. After menopause, a woman's LDL level rises while her HDL level falls. Thus, her risk of heart disease continues to rise with age. After menopause, women tend to have higher LDL levels than do men of the same age.

These health conditions may increase a person's risk for high cholesterol:

• alcohol abuse
• diabetes
• kidney disease
• liver disease
• underactive thyroid gland, called hypothyroidism

These medicines may raise total cholesterol level:

• anabolic steroids
• certain types of medicine to lower blood pressure, such as clonidine and methyldopa
• some diuretics, also called water pills
• progestins

These medicines may reduce HDL ('good" or "healthy") cholesterol:

• anabolic steroids
• some beta-blockers
• some progestins

What can be done to prevent the disease?

Adults 20 years or over should be tested every five years for cholesterol, LDL, HDL, and triglycerides (with a lab test called a lipid profile). Some factors that affect cholesterol cannot be controlled. High cholesterol can run in families, for example, due to genetic factors. Many cases of high cholesterol can be prevented by choosing a healthy lifestyle.

Recommendations include the following:

• eating a heart-healthy diet low in cholesterol and saturated fat
• exercising regularly
• maintaining a healthy body weight
• limiting alcohol intake
• not smoking
• seeking effective treatment for diabetes, hypothyroidism, and other health conditions

How is the disease diagnosed?

A blood cholesterol test is used to diagnose high cholesterol. This test, called a lipid profile, measures total cholesterol, LDL, HDL, and the triglycerides.

Total cholesterol results are evaluated as follows:

• desirable range is less than 200 milligrams per deciliter or mg/dL
• borderline-high is 200 to 239 mg/dL
• high cholesterol is 240 mg/dL or greater

LDL results in healthy adults are evaluated as follows:

• optimal is less than 100 milligrams per deciliter, or mg/dL
• near optimal/above optimal is 100 to 129 mg/dL
• borderline high is 130 to 159 mg/dL
• high is 160 to 189 mg/dL
• very high is 190 mg/dL or greater

LDL results are evaluated differently in people with certain risk factors. If a person has diabetes, or already has clinically apparent coronary artery disease, or if he shows other clinical signs of atherosclerosis, such as peripheral arterial disease, abdominal aortic aneurysm, or certain types of carotid artery disease, he should maintain an HDL level below 100 mg/dL.

For people who do not yet have any of the above conditions, their optimal LDL level is based on their computed risk of developing CAD within 10 years, using data from the Framingham heart study. This 10-year risk is calculated from a formula that takes the following into account:

• age
• cigarette smoking
• HDL cholesterol
• systolic blood pressure, which is the top number on a blood pressure reading
• total cholesterol
• treatment for high blood pressure

LDL results in healthy adults are evaluated as follows:

• optimal is less than 100 milligrams per deciliter, or mg/dL
• near optimal/above optimal is 100 to 129 mg/dL
• borderline high is 130 to 159 mg/dL
• high is 160 to 189 mg/dL
• very high is 190 mg/dL or greater

The LDL targets are:

• less than 100 mg/dL for people with a combination of the above risk factors that puts their CAD risk at 20% or higher in 10 years
• less than 130 mg/dL for individuals with two or more risk factors
• less than 160 mg/dL for people with no or one risk factor

The lower the HDL level, the higher the risk for CAD.

What are the long-term effects of the disease?

High levels of total and LDL cholesterol greatly increase the risk of atherosclerosis, coronary artery disease, and stroke. High cholesterol levels following a heart attack increase the chance of a second heart attack.

What are the risks to others?

High cholesterol is not contagious. However, some forms of high cholesterol run in families.

What are the treatments for the disease?

Recently, treatment of high cholesterol has shifted from total cholesterol to LDL cholesterol. Treatment focuses on reduction of LDL cholesterol to the optimal level, whenever possible. LDL can be lowered with therapeutic lifestyle changes (TLC). It can also be reduced with medications.

Therapeutic lifestyle changes include regular physical activity and weight reduction. TLC also includes the following dietary guidelines:

• 20-30 grams of total fiber per day
• 10-25 grams of soluble fiber per day
• saturated fat less than 7% of daily calories
• polyunsaturated fat less than 10% of daily calories
• monosaturated fat up to 20% of daily calories
• total fat 25-35% of daily calories
• carbohydrates 50-60% of daily calories
• protein at 15% of daily calories
• cholesterol less than 200 mg per day

TLC guidelines also recommend 2 grams of plant sterols/esters per day. Plant sterols are naturally found in fruits, vegetables, nuts, seeds, cereals, legumes, and other plant-based foods. Plant sterol esters are found in food products, such as certain salad dressings and food spreads.

Cholesterol-lowering medications are recommended for people whose short or long-term risk of CAD is high. These medications include:

• bile acid resins, such as cholestyramine (i.e., Questran) and colestipol (i.e., Colestid)
• nicotinic acid, also known as niacin (i.e., Niaspan, Slo-Niacin) or vitamin B3
• fibric acids, such as gemfibrozil (i.e., Lopid) and fenofibrate (i.e., Antara, Libofen, Lofibra, Tricor, Triglide)
• statins, such as atorvastatin (i.e., Lipitor), fluvastatin (i.e., Lescol, Lescol XL), lovastatin (i.e., Altoprev, Mevacor), pravastatin (i.e., Pravachol), rosuvastatin (i.e., Crestor) and simvastatin (i.e., Zocor)
• agents that prevent cholesterol absorption from the small intestine such as ezetimibe (i.e., Zetia)
• omega-three fatty acids (i.e., Omacor)
• combinations of the above agents

• ezetimibe and simvistatin (i.e., Vytorin)
• lovastatin and niacin (i.e., Advicor)

The choice of medications is based on the cholesterol level, the person's age, and any other health conditions.

What are the side effects of the treatments?

The side effects depend on the particular medication chosen. Most cholesterol-lowering medicines can have bad effects on the liver. Blood tests are often done to measure the levels of enzymes produced by the liver. Niacin can cause flushing of the skin and itching. It may also cause nausea, vomiting, diarrhea, and high blood glucose.

What happens after treatment for the disease?

Treatment of high total and LDL cholesterol is lifelong. Diet, exercise, and a healthy lifestyle are key to quality of life.

How is the disease monitored?

The individual will have regular cholesterol tests and visits with the healthcare provider. Any new or worsening symptoms should be reported to the provider.