What is Cholesterol?
Cholesterol helps your body build new cells, insulate nerves, and produce hormones. Normally, the liver makes all the cholesterol the body needs. But cholesterol also enters your body from food, such as animal-based foods like milk, eggs, and meat. Too much cholesterol in your body is a risk factor for heart disease.
How Does High Cholesterol Cause Heart Disease?
When there is too much cholesterol in your blood, it builds up in the walls of your arteries, causing a process called atherosclerosis, a form of heart disease. The arteries become narrowed and blood flow to the heart muscle is slowed down or blocked. The blood carries oxygen to the heart, and if not enough blood and oxygen reach your heart, you may suffer chest pain. If the blood supply to a portion of the heart is completely cut off by a blockage, the result is a heart attack.
There are two forms of cholesterol that many people are familiar with: Low-density lipoprotein (LDL or "bad" cholesterol) and high-density lipoprotein (HDL or "good" cholesterol.) These are the form in which cholesterol travels in the blood.
LDL is the main source of artery-clogging plaque. HDL actually works to clear cholesterol from the blood.
What Are the Symptoms of High Cholesterol?
High cholesterol itself does not cause any symptoms, so many people are unaware that their cholesterol levels are too high. Therefore, it is important to find out what your cholesterol numbers are. Lowering cholesterol levels that are too high lessens the risk for developing heart disease and reduces the chance of a heart attack or dying of heart disease, even if you already have it.
What Numbers Should I Look For?
Some recommend that everyone over age 20 should get their cholesterol levels measured at least once every 5 years. The test that is performed is a blood test called a lipoprotein profile. That includes:
- Total cholesterol level
- LDL (the "bad" cholesterol)
- HDL (the "good" cholesterol)
Here's how to interpret your cholesterol numbers:
|Less than 200||Desirable|
|200 - 239||Borderline High|
|240 and above||High|
|LDL Cholesterol||LDL-Cholesterol Category|
|Less than 100||Optimal|
|100 - 129||Near optimal/above optimal|
|130 - 159||Borderline high|
|160 - 189||High|
|190 and above||Very high|
|60 or more||Desirable - helps to lower risk of
|Less than 40||Major risk factor -- increases the
risk for developing heart disease
*HDL (good) cholesterol protects against heart disease, so for HDL, higher numbers are better.
|Less than 150||Normal (desirable)
What Affects Cholesterol Levels?
A variety of factors can affect your cholesterol levels. They include:
- Diet. Saturated fat, trans fat, carbohydrates, and cholesterol in the food you eat increase cholesterol levels. Reducing the amount of saturated fat, trans fats and sugars in your diet helps lower your blood cholesterol level. Increasing the amount of fiber and plant-derived sterols can also help lower LDL cholesterol.
- Weight. In addition to being a risk factor for heart disease, being overweight can also increase your cholesterol. Losing weight can help lower your LDL, total cholesterol levels, and triglyceride levels, as well as raise your HDL.
- Exercise. Regular exercise can lower LDL cholesterol and raise HDL cholesterol. You should try to be physically active for 30 minutes every day.
- Age and Gender. As we get older, cholesterol levels rise. Before menopause, women tend to have lower total cholesterol levels than men of the same age. After menopause, however, women's LDL levels tend to rise.
- Heredity. Your genes partly determine how much cholesterol your body makes. High blood cholesterol can run in families.
- Medical conditions. Occasionally, a medical condition may cause an elevation of cholesterol levels in the blood. These include hypothyroidism (an underactive thyroid gland), liver disease and kidney disease.
- Medications. Some medicines, like steroids and progestins, may increase "bad" cholesterol and decrease the "good" cholesterol.
How Is High Cholesterol Treated?
The main goals in treating high cholesterol are to lower your LDL levels and lower your risk of cardiovascular disease. To lower cholesterol, eat a heart-healthy diet, exercise regularly, and maintain a healthy weight. Some may also need to take cholesterol-lowering drugs.
Doctors determine your "goals" for lowering LDL based on the number of risk factors you have for heart disease.
Major risk factors include: age (men 45 years and older, women 55 years and older), cigarette smoking, high blood pressure, an HDL less than 40 mg/dL, family history of premature heart disease in a first-degree male relative (father or brother) less than age 55 and first-degree (female) relative less age 65.
- If you have 0-1 risk factor for heart disease, you are at low-to-moderate risk. Generally, lifestyle changes are effective in keeping the cholesterol in check.
- If you have 2 or more risk factors for heart disease, you are at moderate risk, depending on what heart disease risk factors you have. Your doctor may recommend lifestyle changes, but most people require cholesterol-lowering drugs, along with an appropriate diet and exercise program.
- If you have known heart disease, diabetes, or multiple risk factors, you are at high risk. Most people in this group will require a combination of cholesterol-lowering drugs and lifestyle changes to control their cholesterol levels.
LDL cholesterol goals include the following:
- Category I, Highest Risk (ten-year risk greater than 20%*): your LDL goal is less than 100 mg/dL. For those with a very high risk (those who have had a recent heart attack, those with cardiovascular disease or peripheral artery disease combined with diabetes or poorly controlled risk factors, or those with metabolic syndrome), it may be most effective for the LDL goal to be less than 70 mg/dL.
- Category II, Next Highest Risk (ten-year risk 10-20%*): your LDL goal is less than 130 mg/dL. Your doctor may set your LDL goal at less than 100 mg/dl if your LDL is 100-129.
- Category III, Moderate Risk (ten-year risk less than 10%*): your LDL goal is less than 130 mg/dL. Your doctor may set your LDL goal at less than 100 mg/dl if your LDL is 100-129.
- Category IV, Low Risk (0-1 risk factor*): your LDL goal is less than 160 mg/dL.
*Risk categories are based on the Framingham Heart Study to estimate 10-year risk for coronary heart disease (heart attack and coronary death). It is based on adults ages 20 and older who do not have heart disease or diabetes. The risk factors included in the Framingham calculation are age, total cholesterol, HDL cholesterol, systolic blood pressure, treatment for high blood pressure, and cigarette smoking.
To reduce your risk for heart disease or keep it low, it is very important to:
- Control any other risk factors you may have, such as high blood pressure and smoking.
- Follow a low saturated fat, low refined carbohydrate eating plan
- Maintain a desirable weight.
- Participate in regular physical activity.
- Begin medication therapy as directed by your doctor.
What Drugs Are Used to Treat High Cholesterol?
Cholesterol-lowering drugs include:
- Bile-acid resins
- Fibric acid derivatives
- Cholesterol absorption inhibitors
Cholesterol-lowering medicine is most effective when combined with a healthy diet and exercise program.
Statins block the production of cholesterol in the liver itself. They lower LDL, the "bad" cholesterol, and triglycerides and have a mild effect in raising HDL, the "good" cholesterol. These drugs are the first line of treatment for most people with high cholesterol.
Statins carry warnings that memory loss, mental confusion, high blood sugar, and type 2 diabetes are possible side effects. It's important to remember that statins may also interact with other medications you take.
Examples of statins include:
- Atorvastatin (Lipitor)
- Fluvastatin (Lescol)
- Lovastatin (Altocor, Altoprev, Mevacor)
- Pitavastatin (Livalo)
- Pravastatin (Pravachol)
- Rosuvastatin calcium (Crestor)
- Simvastatin (Zocor)
Advicor and Simcor are both combinations of a statin and niacin (see below).
Caduet is a combination of a statin (Lipitor) and a blood pressure-lowering drug called Norvasc. Vytorin is a combination of a statin and a cholesterol absorption inhibitor (simvastatin and ezetimibe).
Niacin is a B-complex vitamin. It's found in food, but is also availableat high doses by prescription. It lowers LDL cholesterol and raises HDL cholesterol. These drugs also lower elevated triglycerides. The main side effects are flushing, itching, tingling, and headache, yet aspirin can reduce many of these symptoms. However, speak with your doctor first. Niacin or nicotinic acid, includes the brand names Niacor, Niaspan, or Slo-niacin. Over-the-counter preparations include extended-release, timed-release, and controlled-release. Niacin found in dietary supplements should not be used to lower cholesterol. Your doctor or lipid specialist will let you know if niacin is appropriate for you. Recent research suggests that niacin may improve cholesterol numbers, but may not be associated with prevention of heart attacks.
Bile Acid Sequestrants
These drugs work inside the intestine, where they bind to bile and prevent it from being reabsorbed into the circulatory system. Bile is made largely from cholesterol, so these drugs work by reducing the body's supply of cholesterol, thus lowering total and LDL cholesterol. The most common side effects are constipation, gas, and upset stomach. Examples of bile acid resins include:
Fibrates lower triglyceride levels and can increase HDL and lower LDL cholesterol. The mechanism of action is not clear, but it is thought that fibrates enhance the breakdown of triglyceride-rich particles and decrease the secretion of certain lipoproteins. In addition, they induce the synthesis of HDL.
Examples of fibrates include:
- Fenofibrate (Antara, Lipofen, Lofibra, Tricor)
- Fenofibric acids (Fibricor, Trilipix)
- Gemfibrozil (Lopid)
Selective cholesterol absorption inhibitors
Ezetimibe (Zetia) works to lower LDL by inhibiting the absorption of cholesterol in the intestines. Vytorin is a newer drug that is a combination of ezetimibe (Zetia) and a statin (simvastatin), and can decrease total and LDL cholesterol and raise HDL levels. There is not sufficient medical evidence to show that ezetimibe prevents heart attacks.
Combination drugs Some people with high cholesterol achieve the best results with combination drugs. These drugs treat cholesterol problems and are sometimes combined with medications like blood pressure drugs in one pill. Some examples include:
- Advicor: Lovastatin and niacin ( nicotinic acid )
- Caduet: Atorvastatin and amlodipine , a calcium channel blocker
- Liptruzet: Atorvastatin and ezetimibe
- Simcor: Simvastatin and niacin (nicotinic acid)
- Vytorin: Simvastatin and ezetimibe , a cholesterol absorption inhibitor
What Are the Side Effects of Cholesterol-Lowering Drugs?
The side effects of cholesterol-lowering drugs include:
- Muscle aches*
- Abnormal liver function
- Allergic reaction (skin rashes)
- Abdominal pain
- Decreased sexual desire
- Memory problems
*If you have muscle aches, call your doctor immediately. This could be a sign of a life-threatening condition.
Are There Foods or Other Drugs I Should Avoid While Taking Cholesterol-Lowering Drugs?
Ask your doctor about the other drugs you are taking, including herbals and vitamins, and their impact on cholesterol-lowering drugs. You should not drink grapefruit juice while taking some types of cholesterol-lowering drugs, as it can interfere with the liver's ability to metabolize these medications.