Monday, December 22, 2008

From the Monitor

One heart—many threats
Psychologists take on heart disease: the nation’s number one killer.
By Rebecca A. ClayPrint version: page 46
Every 35 seconds, an American dies of heart disease or stroke. In fact, cardiovascular diseases kill more Americans than any other. Meanwhile, more than 70 million live with these conditions, according to the U.S. Centers for Disease Control and Prevention.
And since cardiovascular diseases are more common in people 65 and older, the numbers are poised to go up as the baby boomers age.
Cardiologists aren’t the only ones working to vanquish these deadly diseases. A field known as psychocardiology—also called behavioral cardiology or cardiac psychology—is encouraging psychologists to offer their own expertise. Researchers in the area are uncovering how psychosocial factors such as low socioeconomic status, depression and hostility contribute to cardiovascular disease (see “Don't be mad”). Some studiessuggest, for example, propensities for high levels of stress hormones among people with depression and increased coronary calcification among people of low socioeconomic status.
Psychologists are developing smoking-cessation programs and other interventions designed to help prevent disease (see “Building a stronger heart”) in such populations as well as interventions designed to help patients who already have it cope. They’re also hoping for a future in which psychological and cardiological care are more integrated.
“My dream is that we have real cooperation between psychologists and cardiologists,” says Jochen Jordan, PhD, co-editor of the new APA book “Contributions Toward Evidence-based Psychocardiology: A Systematic Review of the Literature” and director of the Clinic for Psychocardiology at the Kerckhoff Clinic in Bad Nauheim, Germany.
Exploring psychosocial factors
Psychocardiology’s roots go back to the 1920s, say Jordan and his fellow contributors, when research began on the psychosocial characteristics that can threaten heart health. Since then, they say, that line of research has not only flourished but broadened.
Some researchers have focused on internal risk factors. Psychological problems like depression, anxiety and social isolation seem to predict both the development of disease in healthy people and complications in those who are already patients, says Robert M. Carney, PhD, director of the Behavioral Medicine Center and a psychiatry professor at Washington University School of Medicine in St. Louis, Mo.
Carney’s own work focuses on depression. While past research by Carney and others has found that depression may double people’s chances of developing heart disease and triple their chances of dying once they have it, his current research looks at the underlying mechanisms.
It’s not just that depressed people often don’t exercise, eat right or take their medications, says Carney. There may be physiological mechanisms at work, too.
In a 2005 literature review in Psychosomatic Medicine (Vol. 67, Suppl. 1, pages 529–533), for example, Carney and co-authors note that medically well but mentally depressed people had high levels of stress hormones and that depressed heart patients had elevated heart rates, exaggerated responses to physical stressors and other indicators of dysfunction.
“It’s paradoxical,” says Carney. “If you look at people who are depressed, you usually don’t see a lot of activity. But physiologically, they seem to be in a state of hyper-arousal.”
Carney’s own research focuses on why this dysfunction puts people at risk of arrhythmias, heart attacks and the like. Likely suspects include inflammation and platelet dysfunction that encourages coagulation, both of which are more common in depressed people.
Other psychologists are exploring the role of the external environment. Karen A. Matthews, PhD, for example, focuses on the role of socio-economic status.
“At the beginning of the 20th century, it was the upper class that tended to have heart disease,” says Matthews, co-director of the Pittsburgh Mind-Body Center and a professor of psychiatry, epidemiology and psychology at the University of Pittsburgh School of Medicine. “Now it’s concentrated in people who have low education, low income and low-prestige jobs.”
Matthews and other researchers have found elevated cardiovascular risk—a harbinger of future heart disease—even in adolescents of low socioeconomic status. In a 2003 paper in Psychological Bulletin (Vol. 129, No. 1, pages 10–51), Matthews and her colleague Linda Gallo, PhD, proposed an explanation for why that is.
Focusing on “reserve capacity,” the model begins with the idea that people with lower socioeconomic status have fewer psychological, social and economic resources than their better-off peers; those resources then deteriorate further under constant bombardment by acute and chronic stressors ranging from discrimination to bad jobs to crime. The heightened physiological responsiveness and unhealthy behaviors that come with stress leave these individuals at risk of heart disease.
Developing interventions
Other psychologists are searching for ways to put this knowledge into practice. While some researchers are developing programs to help patients stop smoking, comply with medical regimens and tackle other behavioral risk factors, many are focused on stress management. The hope is to show that such interventions save lives.
So far, researchers haven’t been able to prove that. In a 2003 Journal of the American Medical Association (JAMA) article (Vol. 289, No. 23, pages 3,106–3,116), researchers described the disappointing findings of the Enhancing Recovery in Coronary Heart Disease (ENRICHD) study of 2,481 heart attack patients at eight clinical centers. While cognitive-behavioral therapy and antidepressants did improve patients’ depression and isolation, the intervention did not have any impact on subsequent heart attacks or death.
James A. Blumenthal, PhD, one of the ENRICHD researchers, isn’t daunted. In a 2005 JAMA article (Vol. 293, No. 13, pages 1,626–1,634), he and his co-authors revealed the results of a randomized study of exercise, stress management and standard medical therapy for 134 heart patients. The intervention groups saw improvements in endothelial function and other measures of arterial health; they also felt less distressed and depressed.
“Stress management may very well be an intervention you’d want every cardiac rehabilitation patient to be exposed to,” says Blumenthal, a professor of psychiatry and behavioral sciences and professor of psychology and neuroscience at Duke University. “It has the potential to not only improve their quality of life but also potentially impact their medical health outcomes.”
In an earlier study in the American Journal of Cardiology (Vol. 90, No. 1, pages 86–87), Blumenthal and his colleagues reported that stress management also lowers costs. Heart patients who had participated in weekly stress-management classes had fewer medical problems and lower medical costs than those who received usual care.
“Stress management is relatively inexpensive to deliver when you compare it to angioplasty or bypass surgery, yet it could result in long-term cost savings,” says Blumenthal.
Other psychologists focus on quality of life.
Samuel F. Sears Jr., PhD, for instance, helps patients with implantable cardiac defibrillators (ICDs) cope with anxiety about the device, which provides a powerful, unexpected shock when it detects arrhythmia.
“ICD patients have potentially life-threatening arrhythmias that are treated with high-energy shocks that come out of the blue,” says Sears, an associate professor of clinical and health psychology at the University of Florida Health Science Center in Gainesville. “They have fear of death, fear of shocks and fear of device malfunction.”
Psychological interventions can quell those fears, says Sears. In a study of 88 patients with newly implanted ICDs published in 2004 in the Journal of Cardiopulmonary Rehabilitation (Vol. 24, No. 4, pages 324–331), he identified optimism and positive health-related expectations as important predictors of subsequent quality of life.
“We can modify patients’ expectations and provide information to prepare them for what to expect,” says Sears, who has also developed a measurement tool called the Florida Shock Anxiety Scale to help identify patients who need assistance.
Integrating psychology into cardiac care
Are cardiologists, and the health-care system as a whole, putting these findings into practice?
Not necessarily, says David S. Krantz, PhD, past-president of APA’s Div. 38 (Health) and professor and chair of the medical and clinical psychology department at the Uniformed Services University of the Health Sciences in Bethesda, Md.
Although acceptance of psychocardiology is growing, says Krantz, challenges remain. For one thing, he says, getting third-party payers to support cardiac rehabilitation in general—let alone the psychological aspect—is increasingly difficult. Jochen Jordan and his co-authors note that hospital stays in the United States are shortening, so there’s little time for inpatient rehabilitation. And when it comes to outpatient rehab, they say, the focus is on exercise since insurance companies often won’t pay for other services.
“Rehabilitation costs,” says Krantz, “so they’re cutting the money for it.”
In addition, he says, practitioners need to learn the ins and outs of heart disease since general clinical practitioners don’t have the specialized training necessary.
Researchers need to develop interventions targeted to specific subpopulations of heart patients. And psychologists need to do a better job communicating the value of collaboration.
“I’d like to see psychocardiology integrated into the prevention of cardiovascular disease and the comprehensive care of patients,” says Krantz. “I’d like to see psychology and cardiology seeing each other’s strengths and having mutual respect.”
In an effort to make that vision a reality, Jordan helped establish Germany’s first dedicated psychocardiology clinic. The 18-bed facility offers everything from smoking cessation and weight-loss programs to therapy for heart transplant patients to advice for couples. The clinic even offers weekend seminars for cardiologists on topics like how to discuss sexuality with patients.
Even in Germany, with its long tradition of rehabilitation in health spas and its guaranteed insurance coverage, money is an issue. The medical community views new drugs, devices and machines as money-makers, says Jordan, and views psychological services as a luxury it can’t afford. He hopes that over the next two or three years, the clinic will prove its economic viability.
Jordan also hopes the clinic will serve as a model for putting the research described in “Contributions Toward an Evidence-based Psychocardiology” into practice.
Ten years ago, he explains, cardiologists were still skeptical of psychologists’ often-contradictory research findings and weren’t cooperating with psychologists in their practices.
“Now,” says Jordan, “they are friendly and interested and slowly changing the way they practice.”