Duke researchers look at coronary artery disease for frail and elderly

Durham, N.C. — A new study from Duke University Medical Center, released Monday, finds that patients treated solely with medications after suffering from chest pain, heart attack or coronary artery disease are more likely to die during the first year following their initial hospitalization.

"Patients managed medically without stenting or bypass surgery tend to be elderly and frail, and in some sense we feel they have been overlooked," says Dr. Matthew Roe, a cardiologist at Duke and the senior author of the study appearing in the August issue of the Journal of the American College of Cardiology: Cardiovascular Intervention. "We wanted to find out what clinical factors were funneling them into a medicine-only group and what happened to them, when compared [with] patients who received stents and bypass procedures."

Roe led a team of researchers in examining a subset of 8,225 patients from a previous study (the SYNERGY trial) that had compared the effects of two different anti-clotting drugs in heart patients. For the new study, researchers included only patients who had undergone cardiac catheterization and who had been found to have at least one significant blockage in a coronary artery. A majority of these patients (52 percent) underwent coronary stent implantation to open their arteries, while 32 percent were medically managed and 16 percent underwent coronary bypass surgery.

Investigators discovered that patients in the medical management group were more likely to be elderly women with low body weight and more likely to have had peripheral artery disease, high blood pressure, diabetes, a history of stroke or a previous bypass surgery.

Researchers found that with all else being equal, the risk of death was highest for the medically managed group and lowest for patients who underwent stenting. Death rates among medically managed patients increased rapidly during the first three months following release from the hospital and stayed higher than those in the other two groups. At one year, the mortality rates were 7.7 percent among the medically managed group, 3.6 percent for patients who underwent stenting and 6.2 percent among those who underwent bypass procedures.

"It is important to know that the patients in the medically managed group had a higher death rate despite receiving most of the currently recommended medications for this condition from clinical practice guidelines," Roe said. "There are often very good reasons why stenting or bypass are not viable options for some patients. What this study tells us is that for these patients who are medically managed, we need to come up with better treatment approaches that lessen their risk of death."

Roe says possible solutions may arise from a new trial that is just getting under way. The new study, called TRILOGY will compare clopidogrel (Plavix) with the experimental drug prasugrel, another anti-clotting agent, among elderly and frail medically managed patients with chest pain and coronary artery disease. An earlier trial found that prasugrel was effective in reducing the risk of clotting, but it also brought about a higher risk of bleeding. The TRILOGY trial will compare the two drugs again, but will study a lower dose of prasugrel than in the earlier study.

The Duke Clinical Research Institute will manage TRILOGY, which is expected to enroll approximately 10,000 patients in hundreds of hospitals worldwide.

Colleagues from the Duke Clinical Research Institute who contributed to the published study include Mark Chan, Kenneth Mahaffey, Lena Sun, Karen Pieper and Robert Califf. Co-authors from other institutions include Harvey White, from Aukland City Hospital, New Zealand; and Philip Aylward and James Ferguson from the Texas Heart Institute.

The SYNERGY trial was funded by Sanofi-Aventis.