Heart attack prevention within three months after hospitalization significantly averted future attacks

Nov 10 2008

Despite substantial progress in the diagnosis and treatment of heart attack patients, prevention of recurrent heart attacks continues to be a major clinical challenge.

A new study showed that patients who suffered a non-fatal heart attack within the first three months of hospitalization for chest pain had a significantly higher risk for dying or having another heart attack (in the following three months to four years) compared with patients who did not experience a heart attack during the same initial period. The findings from the more-than-15,000- patient study were presented today at the annual meeting of the International Society for Pharmacoeconomics and Outcomes Research (ISPOR), November 8-11.

In the study, patients who suffered a heart attack during the first three months after hospital admission for coronary artery disease compared with those who did not experience a heart attack during the same period were 62 percent (p<0.001) more likely to die and 84 percent (p<0.001) more likely to have an additional heart attack or death within four years. The increased rate of heart attack and death among patients who had a heart attack remained similar even when the monitoring was extended from a three-to-six month period. The researchers found that patients who suffered a heart attack within the six month period were 61 percent (p<0.001) more likely to die, and 86 percent (p<0.001) were more likely to suffer a recurrent heart attack or death over a four-year period compared with those who did not experience a heart attack.

"This study illustrated that heart attack patients may still suffer severe, life-threatening events over the next several years, even if they appear well," said study investigator David F. Kong, M.D., assistant professor of medicine, Division of Cardiovascular Medicine, Duke University Medical Center & Duke Clinical Research Institute, Durham, N.C., USA. "Surviving an initial heart attack does not mean that a patient is 'out of the woods'. Earlier diagnosis and interventions to help prevent heart attacks could improve long-term outcomes for patients."

The study analyzed 15,604 patients with significant coronary heart disease undergoing diagnostic catheterization, a procedure in which a thin plastic tube is inserted into an artery to take pictures of the blood vessels that supply the heart. Patients were classified as having a non-fatal heart attack within three months of their first catheterization in a hospital or as being event-free within the three-month period. The median follow-up time for both groups was 4.2 years.

In the retrospective analysis, patients in the heart attack vs. no heart attack group were similar in age (median of 62 vs. 63), female sex (36 percent vs. 33 percent), history of hypertension (69 percent vs. 68 percent), history of diabetes (36 percent vs. 30 percent) and multi-vessel coronary artery disease (61 percent vs. 58 percent). The median follow-up time for both groups was 4.2 years.

The study was conducted at Duke Clinical Research Institute, part of Duke University Medical Center, by Eric Eisenstein, D.B.A., Patricia Cowper, Ph.D., David Kong, M.D., and Kevin Anstrom, Ph.D., with support from the Health Outcomes groups at Daiichi Sankyo and Lilly.

As one of the primary forms of cardiovascular disease, coronary heart disease occurs when the coronary arteries become narrowed or clogged by cholesterol and fat deposits inside the arteries through a process called atherosclerosis. Heart attacks are a major manifestation of coronary heart disease, which constitutes an enormous health burden throughout the world. Annually, 3.8 million men and 3.4 million women worldwide die from coronary heart disease.(1) The rates of death in coronary heart disease patients are particularly high. Of all patients who die within 28 days after the onset of symptoms, approximately two-thirds die before reaching the hospital.(2) Long- term prevention of heart attacks and further cardiac events in patients who already experienced a non-fatal heart attack is crucial to improve the lives of coronary heart disease patients.