The researchers, led by Karina Davidson, PhD, studied the association with heart disease of various factors, including depression, anger, and hostility. When they examined the differences between self-reported and observed hostility, however, they found that only observed hostility was associated with heart disease.
They measured both self-reported and observed hostility among 1,749 participants in the 1995 Nova Scotia Health Survey who were free of ischemic heart disease. (Ischemic, or coronary artery, disease results in reduced blood supply to the heart.) Public health nurses measured the participants’ hostility levels based on their videotaped responses to questions about various stressful situations.
When the researchers followed the participants for 10 years, they found that those with observed hostility were more likely (8.9 percent versus 5.1 percent of those without observed hostility) to develop ischemic heart disease. The level of hostility had no apparent effect—only whether a participant was hostile.
“A high percentage—close to 90 percent—of the participants had some degree of observed hostility,” said Dr. Davidson. “Therefore, rather than think of hostility as a risk factor for ischemic artery disease, it may be more useful to think of the lack of hostility as protective against it.”
“We have no evidence that faking it—covering your hostility with a pasted-on smile—is any help,” she added. A better approach would be to look at possible contributing causes to the hostility, such as overwhelming daily stresses or poor health habits.”
“Observed Hostility and the Risk of Incident Ischemic Heart Disease” was published in the Sept. 13, 2011, issue of the Journal of the American College of Cardiology.