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Treadmill Testing not Recommended for Screening Patients at Low Risk for Heart Disease

The recommendations are published in the February 17 issue of Annals of Internal Medicine, and further information about the three screening tests can be found on the AHRQ Web site at http://www.ahrq.gov/clinic/uspstf/uspsacad.htm.

The U.S. Preventive Services Task Force said today that it does not recommend using treadmill exercise testing, resting electrocardiograms, or electron beam computerized tomography to screen for heart disease in low-risk adults who don’t have any symptoms of heart disease. For adults at increased risk for heart disease, the Task Force found insufficient evidence for or against using these three tests for screening.

An estimated 22 million Americans have heart disease, and more than 700,000 die from it each year. Heart disease is the leading killer of both men and women and is estimated to cost more than $350 billion annually in medical care, time lost from work and other expenses.

Men under age 50 and women under age 60 who have normal blood pressure and cholesterol levels, do not smoke, and do not have diabetes are at low risk of heart disease. A simple calculator to estimate risk of heart disease can be found at http://hin.nhlbi.nih.gov/atpiii/calculator.asp?usertype=pub.

The Task Force recommends screening for many of the risks for heart disease, such as high blood pressure, obesity, diabetes, and high cholesterol. The Task Force found that while treadmill testing, EKG, and EBCT could identify persons at higher risk of heart disease, no studies to date have examined whether or not using these tests to screen adults improves health outcomes. Furthermore, the Task Force concluded that using these three technologies to screen for heart disease in low-risk adults could cause more harm than good because of the frequency of false-positive and false-negative results.

The Task Force said that the evidence is inadequate to determine how test results would change the course of treating patients and noted concern that potential harms, such as false-positive findings, unnecessary invasive procedures, and over-treatment could outweigh any benefit of the tests in lower risk persons.

False-positive results, in addition to causing a patient psychological stress and anxiety, often lead to invasive tests, such as coronary angiography or treatment with unnecessary medications. Although coronary angiography—a test in which a catheter is inserted into the patient and a dye injected—is considered generally safe, complications, such as internal bleeding, stroke or infection, and even death, can occur. False-negative results can mislead those with heart disease and result in delayed treatment.

“These recommendations can help clinicians and their patients make more informed decisions about use of these tests to screen for heart disease and may help guide employers and insurers as well,” said Task Force chair, Ned Calonge, M.D., Chief Medical Officer and State Epidemiologist for the Colorado Department of Public Health and Environment. “The most important thing individuals at low risk can do is to work with their clinician to monitor their blood pressure, cholesterol, and weight, and to be physically active.”

The Task Force, sponsored by the Agency for Healthcare Research and Quality, is the leading independent panel of private-sector experts in prevention and primary care and conducts rigorous, impartial assessments of the scientific evidence for a broad range of preventive services. Its recommendations are considered the gold standard for clinical preventive services. The Task Force based its conclusions on a report from a research team led by Michael Pignone, M.D., M.P.H., Assistant Professor of Medicine at the University of North Carolina- Chapel Hill School of Medicine and the RTI International-University of North Carolina Evidence-based Practice Center.

The Task Force grades the strength of the evidence as “A” (strongly recommends), “B” (recommends), “C” (no recommendation for or against), “D” (recommends against), or “I” (insufficient evidence to recommend for or against screening). The Task Force recommends against routine screening with resting electrocardiogram, exercise treadmill test, or electron beam computerized tomography scanning for coronary calcium, for either the presence of severe coronary artery stenosis or the prediction of coronary heart disease events in adults at low risk for CHD events (“D” recommendation). For adults at increased risk for CHD events, the Task Force found insufficient evidence to recommend for or against routine screening with EKG, treadmill testing, or EBCT scanning for coronary calcium, for either the presence of severe coronary artery disease or the prediction of CHD events (“I” recommendation).

Previous Task Force recommendations summaries of the evidence on topics related to heart disease are located at http://www.ahrq.gov/clinic/uspstf/uspstopics.htm.