SUMMARIES FOR PATIENTS

Screening for Coronary Heart Disease: Recommendations from the U.S. Preventive Services Task Force

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The summary below is from the full reports titled "Screening for Coronary Heart Disease: Recommendation Statement" and "Exercise Tolerance Testing To Screen for Coronary Heart Disease: A Systematic Review for the Technical Support for the U.S. Preventive Services Task Force." The first report is in the 6 April 2004 issue of Annals of Internal Medicine (volume 140, pages 569-572); the second report is available at http://www.annals.org (volume 140, pages W-9-W-24). The first report was written by the U.S. Preventive Services Task Force; the second report was written by A. Fowler-Brown, M. Pignone, M. Pletcher, J.A. Tice, S.F. Sutton, and K.N. Lohr.

What is the U.S. Preventive Services Task Force?

The U.S. Preventive Services Task Force (USPSTF) is a group of health experts that reviews published research and makes recommendations about preventive health care. The USPSTF and its review of the published research are supported by the Agency for Healthcare Research and Quality.

What is the problem and what is known about it so far?

Coronary heart disease (CHD) is the result of blockages in the heart's blood vessels. Low blood flow to the heart due to blocked vessels causes chest pain or "angina." If it lasts long enough, a section of heart muscle dies, a condition called myocardial infarction or "heart attack." While many people with CHD get symptoms including chest pain or shortness of breath with exertion, others do not know that they have CHD until heart attack occurs. Risk factors for CHD include older age, male sex, high blood pressure, diabetes, smoking, high levels of total or LDL ("bad") cholesterol and low levels of HDL ("good") cholesterol, and family history of CHD. A patient's risk for heart attacks or angina can be determined on the basis of risk factors; several treatments are available to reduce risk for CHD events in patients at increased risk.

Doctors should look for CHD when patients have symptoms that might be due to the disease, but it is unknown whether they should specifically screen healthy patients for CHD. Screening is looking for a disease in patients with no symptoms of that disease. Several tests that might be useful to screen for CHD are available. Electrocardiography (ECG) uses electrodes to examine the heart's electrical activity. An exercise treadmill test (ETT) or "stress test" examines the heart's electrical activity while the patient is exercising. Another way to look for CHD is electron-beam computed tomography (EBCT). This test takes special pictures to look for calcium in the heart's blood vessels. Screening would be justified if it could identify people who need strict management of CHD risk factors or who need procedures to open blocked blood vessels.

How did the USPSTF develop these recommendations?

The USPSTF reviewed published research about the benefits and harms of using ECG, ETT, or EBCT to screen for CHD. Potential benefits would be decreased angina, heart attacks, CHD-related disability, and premature death. Potential harms would be unnecessary testing, treatment, and labeling related to false-positive test results. False-positive test results suggest CHD in patients who do not have the disease.

What did the USPSTF find?

No studies have examined whether ECG, ETT, or EBCT to find CHD in people with no risk factors and no symptoms improves health outcomes. However, many low-risk people will have false-positive results on ECG, ETT, or EBCT. For patients with increased CHD risk, the USPSTF found no studies on whether screening with ECG, ETT, or EBCT results in better health outcomes for patients than simply screening for and treating CHD risk factors. However, false-positive test results are less frequent in people with risk factors.

What does the USPSTF suggest that patients and doctors do?

The USPSTF recommends that doctors not use ECG, ETT, or EBCT to look for CHD in patients with no CHD symptoms or risk factors. The USPSTF recommends neither for nor against using ECG, ETT, or EBCT to look for CHD in patients with CHD risk factors but no CHD symptoms. Doctors and patients should discuss the pros and cons before screening with ECG, ETT, or EBCT.

What are the cautions related to these recommendations?

These recommendations apply only to patients with no symptoms and may change as new studies become available.