Inside Clemson

McCubbin: Stress and the #1 Killer

photo of Jim McCubbin, professor of psychologyBy James A. McCubbin, Ph.D.
Professor of Psychology

Coronary heart disease is the #1 killer of both men and women in the United States. Two risk factors for coronary heart disease are hypertension and psychological stress. I have been studying the role of stress in development of hypertension since my undergraduate years at the University of North Carolina-Chapel Hill, and as a faculty member at Duke University Medical Center, University of Kentucky College of Medicine and Clemson University. My research has been funded by the National Institutes for Health for more than 20 years.

What is psychological stress? Stress is a process whereby we perceive, appraise and respond to environmental events that may be harmful or threatening. Stress produces a fight/flight response that speeds the heartbeat and raises blood pressure. Hypertension is sustained high blood pressure, and affects about a third of all adults in the U.S. Young adults at risk for later development of hypertension have a much larger blood pressure response during stress.

This exaggerated blood pressure response to stress may be a marker for early progression of the disease, or could directly contribute to hypertension development later in life. If stress contributes to the disease process, then early intervention to reduce responses to stress could possibly prevent the development of hypertension before irreversible structural damage occurs.

How does one reduce the health-damaging effects of stress? Our research has shown that aerobic fitness and sufficient sleep are two of the most important lifestyle practices that reduce the effects of stress on blood pressure. We have also shown that relaxation techniques that include control of muscle tension, deep breathing and guided imagery can be effective as well.

Our most current research focuses on brain function in young people at risk for hypertension. We recently discovered that people with higher blood pressure have emotional dampening, a reduced recognition of emotional cues, as in facial expressions or text narratives. It’s like living in a world of email without smiley faces. We put smiley faces in emails to show when we are just kidding. Otherwise some people may misinterpret our humor and get angry.

In complex social situations like work settings, we rely on facial and verbal emotional cues to interact with others. Emotional dampening could decrease social support, and increase hostility and high risk behaviors. All of these factors can increase psychosocial stress and further exacerbate high blood pressure and cardiovascular risk.

Better understanding of brain function in persons at risk for hypertension may lead to improved therapeutic strategies to prevent hypertension and other diseases linked to our physiological, behavioral and cognitive responses to stress.