MONDAY, Sept. 27, 2004 (HealthDayNews) -- A brisk trot on the treadmill can clarify the cardiovascular risk for men who don't have heart disease but who do have risk factors pointing toward future trouble, a new study says.
Men with such risk factors who did poorly on the test were twice as likely to have a heart attack or other major cardiac problem over the next decade compared to those who did well, said a Framingham Heart Study report appearing in the Sept. 28 issue of Circulation.
Exercise stress testing, in which someone goes faster and faster on a treadmill while heart performance is measured, is generally not recommended for routine screening of people with no history of symptoms of heart disease. The new study is the first to evaluate the test among people who have no heart symptoms but do have such risk factors as diabetes, high blood pressure, high cholesterol and smoking.
The study, which included 1,431 such men and 1,621 women, found a doubled risk for men whose heart rate did not reach the expected target rate or who had a heartbeat abnormality called ST-segment depression, compared to men who did not have those problems.
"Our results suggest that exercise testing may be of benefit in asymptomatic men with intermediate to high risk," study author Dr. Gary J. Balady, a professor of medicine at Boston University School of Medicine, said in a statement.
But the test had no predictive value for women, the study found, because the number of cardiac events they experienced was too low to produce meaningful numbers, the researchers reported.
The finding is not likely to increase the use of exercise stress testing, said two cardiologists who evaluated the study.
Treadmill testing usually is not done for someone with no symptoms of heart disease, said Dr. Gerald Fletcher, a preventive cardiologist at the Mayo Clinic and a spokesman for the American Heart Association.
For persons without symptoms who require assessment, such as a middle-aged, inactive man who is about to start an exercise program, "it might be wise to do a stress test of some sort," Fletcher said.
But it is preferable to do a more intensive test, such as treadmill exercise accompanied by an echocardiogram, which give an image of heart performance, he said.
Dr. Reynolds M. Delgado, a staff cardiologist at the Texas Heart Institute, was more definite -- and more negative.
"The only reason to do any test is if there is a good chance that it will change your treatment, and this test has very little ability to do that," Delgado said.
The study shows that an exercise test does have "some prognostic information for men who are at high risk to begin with," Delgado said. But aggressive treatment of specific risk factors would be advisable for those men no matter what an exercise stress test showed, he added.
Another reason for avoiding the exercise test and other, more elaborate screening tests for symptom-free patients such as those in the study is financial, Delgado said: "They are not reimbursable unless the patient has symptoms."
A description of what an exercise stress test entails and what its results mean can be found at the Texas Heart Institute.