For years, physicians have prescribed an exercise stress test primarily for patients who already show such signs of heart disease as chest pain, heart attack or exercise-related cramping. Now, a pair of Hopkins studies offers strong evidence that a stint on a treadmill to measure heart function can help uncover cardiac problems before symptoms occur. The test-which requires a person to gradually walk faster on a treadmill and thus make the heart pump harder to meet the body's increasing demand for oxygen-measures heart rate, blood pressure and the heart's electrical function. Test results can show a lack of blood supply through the arteries that go to the heart.

The researchers scrutinized death rates and causes among 2,001 women and 3,775 men who were given stress tests as part of their participation in the national Lipid Research Clinics Prevalence Study at Hopkins and nine other medical centers beginning in the early 1970s. Results showed that men who had abnormal or inconclusive test results were twice as likely to die of cardiovascular disease as men with normal results. In women, the likelihood was 2.6 times greater.

According to Hopkins cardiology fellow Samia Mora, the studies' lead author, a stress test could be especially valuable for people who have high cholesterol or a family history of heart disease. If the results don't fall within normal limits, physicians would know to step up their monitoring, and patients could be more aggressive about cutting their risk factors.

Don't Ignore the Snore

Parents should be aware that snoring is not necessarily normal in children, and they should discuss it with their doctors, says Carole Marcus, director of Hopkins' pediatric sleep center and head of the American Academy of Pediatrics committee that's issued new evaluation guidelines. Though in some children snoring is just annoying, in many others it can signal the presence of obstructive sleep apnea, a condition that's been associated with daytime tiredness and slow physical growth, and may even by misdiagnosed as attention deficit disorder.

The updated guidelines are published in the April issue of the medical journal Pediatrics and also are available at www.aap.org. Among the recommendations: Pediatricians should screen all children for snoring and rely on a nighttime sleep study to diagnose obstructive sleep apnea. Removal of the tonsils and adenoids is the first line of treatment for most children, followed by postoperative evaluation to determine if additional treatment is needed.