High Cholesterol Diagnosis and Testing
Lifestyle changes (such as diet, weight control, exercise, and smoking cessation) are the first line of defense for treating unhealthy cholesterol levels. If levels still remain high, drug treatment is an effective next step. However, while statins have been shown to slow the rate of atherosclerotic progression, they have not yet been shown to reverse heart disease.
Reducing LDL (“bad” cholesterol) and total cholesterol levels, while at the same time boosting HDL (“good” cholesterol) levels, can prevent heart attacks and death in all people (with or without heart disease). Reducing LDL is the primary goal of most cholesterol therapy. Cholesterol-lowering medications are used along with healthy lifestyle habits, not in place of them. Lowering cholesterol levels with lifestyle changes and drug treatment has been shown to decrease the risk of heart attacks and other complications of atherosclerosis.
The National Cholesterol Education Program’s (NCEP) clinical practice guidelines set treatment goals for LDL levels based on a patient's risk factors for heart disease. The risk factors include:
- Having a first-degree female relative diagnosed with heart disease before age 65 or a first-degree male relative diagnosed before age 55
- Being male and over age 45 or female and over age 55
- Cigarette smoking
- High blood pressure
- Metabolic syndrome (risk factors associated with obesity such as low HDL levels and high triglycerides)
Two or more of these risk factors increases by 20% the chance of having a heart attack within 10 years.
The LDL cholesterol level is one of the most important factors in determining whether a patient needs cholesterol therapy and whether the treatment is working properly. In particular, guidelines emphasize lower LDL levels and earlier treatment for people with coronary artery disease, or other forms of atherosclerosis, and diabetes. (For a table of Cholesterol Goals for Adults, see Introduction section of this report.)
Although current cholesterol goals are extremely useful for most patients, sometimes results of the testing are difficult to interpret and make it difficult for doctors to decide on the appropriate treatment. This is especially true for patients whose test results show:
- Low LDL levels (which are protective) but also low HDL or high triglycerides (which are harmful)
- High total cholesterol levels (which are harmful) but also high HDL levels (which are protective)
Starting Medications. Even modest lowering of high cholesterol levels, whether through drug therapy or lifestyle changes, reduces the risk of disability and death from heart disease. Most drug treatment now focuses on lowering LDL ("bad") cholesterol. A doctor will start or consider medication, increase dosage of medication, or add new medication when a patient’s:
- LDL cholesterol is 190 mg/dL or higher.
- LDL cholesterol is 160 mg/dL or higher AND patient has one risk factor for heart disease.
- LDL cholesterol is 130 mg/dL or higher AND patient has either diabetes or two other risk factors for heart disease.
- LDL cholesterol is 100 mg/dL or higher AND patient has heart disease. (If patient has diabetes, even without heart disease, medication may be considered for an LDL cholesterol of 100 mg/dL.)
- LDL cholesterol is greater than 70 mg/dL AND patient has had a recent heart attack or has known heart disease along with diabetes, current cigarette smoking, poorly controlled high blood pressure, or the metabolic syndrome (high triglycerides, low HDL, and obesity).
Statins are usually the first type of drug used. Statin therapy has been proven to decrease the risk of heart attack, stroke, and the need for coronary revascularization procedures.
In 2010, the FDA approved the statin drug rosuvastatin (Crestor) for prevention of heart attack and stroke in patients with normal LDL cholesterol levels who have a combination of other risk factors that put them at increased risk for heart disease. Rosuvastatin may now be prescribed as primary prevention for men ages 50 years or older or women ages 60 years or older who have:
- High C-reactive protein levels (2 mg/L or higher) AND
- At least one other cardiovascular risk factor (high blood pressure, low HDL cholesterol, smoking, family history of premature heart disease)
C-reactive protein (CRP) is a protein that helps measure inflammation in the body. Increased CRP levels indicate more inflammation and increased risk for heart disease.
Choosing the Correct Lipid-Lowering Medication. Doctors recommend that drug treatments be individually tailored for raising or lowering specific lipids, depending on the patient's blood lipid picture:
- Statins are the standard drugs for most people who require LDL-lowering therapy. Bile-acid binding resins or niacin may be considered. If LDL goals are not achieved, combinations of a statin with a bile-acid resin or niacin should be considered.
- Fibrates or niacin are beneficial for people who need to lower triglycerides and increase HDL.
Considerations for Children and Adolescents. Lifestyle modifications (diet, exercise) are the first course of action for treating children who have unhealthy cholesterol levels or who are at risk for them. In 2008, the American Academy of Pediatrics (AAP) recommended prescribing statin drugs for children age 8 and older who have elevated LDL levels of 190 mg/dLor over. The AAP also recommended statins for children with LDL 160 mg/dL if there is a family history of heart disease or other risk factors.
For children with diabetes, cholesterol drug treatment is recommended when LDL levels are 130 mg/dL. The goal is to lower LDL levels to less than 160 mg/dL or even 110 mg/dL for children with strong risk factors. However, the issue of prescribing statins to children is being hotly debated within the medical community.
Considerations for People with Diabetes. At this time, statins are recommended as the best drugs for improving cholesterol and lipid levels in people with diabetes. Studies suggest that they can reduce the risk for adverse heart events, even if patients' cholesterol levels are normal or if their diabetes is mild. Fibrates may also be useful for some people with type 2 diabetes. Niacin (nicotinic acid) has the best effect on the cholesterol profile of people with diabetes, but it also increases blood sugar levels and can be difficult to tolerate.