A report on the National Heart, Lung and Blood Institute-sponsored research, conducted at the University of North Carolina at Chapel Hill and eight other top U.S. centers, appears in the June 18 issue of the Journal of the American Medical Association. Researchers also presented the findings Tuesday (June 17) at a JAMA media briefing and earlier in less detail at an American Heart Association Scientific Sessions conference in late 2001.
"We were a little disappointed in that we hoped to have better news on this issue for patients," said Dr. Diane Catellier of the UNC School of Public Health. "Still, studies with negative findings are just as important a part of science as studies that turn out positively since they help bring us closer to the truth."
Catellier is a research assistant professor of biostatistics and principal investigator for the study's coordinating center, based at UNC's Collaborative Studies Coordinating Center. Dr. James D. Hosking, research associate professor of biostatistics at UNC, also was instrumental in the work.
The Enhancing Recovery in Coronary Heart Disease Patients Study (ENRICHD) was the first major effort to evaluate the effects of treating depression and low social support in heart attack patients, Catellier said. It also was the largest controlled trial of psychotherapy ever completed.
About a quarter of heart attack (myocardial infarction) patients are either depressed following the incident or have low social support, she said. Those who have either one of the risk factors face up to a four times greater risk of premature death than those who feel reasonably content and have friends and family to support their recovery.
The research involved 73 U.S. hospitals and enrolled 2,481 patients who were depressed, had low social support or both within 28 days of a heart attack. Subjects' average age was 61, 44 percent were women and 34 percent were minorities.
Half received six months of psychological counseling and behavioral therapy, while the other half got only standard medical care. All underwent screening tests to measure depression and social support, and any who remained severely depressed after five weeks of therapy were prescribed antidepressants.
Both groups showed reduced depression and feelings of isolation, but the differences may have been too small to cut the risk of a future heart attack or death, researchers found.
After six months, depressed patients in the treatment group scored significantly better than those in the standard medical care group on a rating method known as the Hamilton depression scale, Catellier said. For the treatment group, investigators saw a 57 percent reduction in depression vs. a 47 percent reduction for the usual medical care group.
Similarly, she said, patients in the treatment group who lacked social support had a 27 percent increase on that measure based on another evaluation method known as the ENRICHD Social Support Instrument compared to an 18 percent improvement in the others.
Despite the treatment group's depression and social support improvement, essentially no change was seen in heart disease survival, Catellier said. After three years, 24 percent of the patients in both the treatment group and the usual care group had either died or suffered a second heart attack.
"This work shows we can improve heart patients' quality of life through this kind of therapy even if we can't change their clinical outcomes overall," she said. "Our next step will be to go back and do a meticulous analysis of this data to determine why the treatment didn't work or to see if certain subgroups of patients do benefit from the therapy."
Dr. Susan Czajkowski of the National Heart, Lung and Blood Institute, project officer and writing committee chair for the study, said that although the intervention did not affect "hard" outcomes, she and her colleagues learned a lot through the unique research.
"The more severe depression is, the greater the risk," Czajkowski said. "This study is the first step along a journey to better understand how these psychosocial risk factors operate to improve overall health. We learned that we can successfully intervene to improve patients' quality of life by lessening their depression and increasing their social functioning. This is in itself a valuable finding, as relatively few -- perhaps 20 to 25 percent -- of heart attack patients who experience depression are treated for this condition."
More studies are needed on psychotherapy, antidepressants and combinations of the two to ascertain the most positive outcomes, she said.
In an accompanying editorial, Drs. Nancy Frasure-Smith and Francois Lesperance at the Montreal Heart Institute also said that despite the negative findings, the study is important.
"The ENRICHD investigators have demonstrated that depressed coronary artery disease (CAD) patients can be identified, randomized, properly treated with complex interventions and followed up for long periods," they wrote. "This is a major accomplishment. However, depression remains a CAD risk factor in search of a successful intervention."
Other universities participating in the research included Duke, Harvard, Stanford, the University of Washington, Washington University, Alabama, Miami and Yale.
By DAVID WILLIAMSON
UNC News Services
Note: Catellier can be reached at (919) 966-1895 or via diane_catellier@unc.edu
School of Public Health Contact: Lisa Katz, (919) 966-7467
News Services Contact: David Williamson, (919) 962-8596
Journal
JAMA