A person who is most prone to anger is about three times more likely to have a heart attack or sudden cardiac death than someone who is the least anger-prone, according to a new study published in Circulation: Journal of the American Heart Association.
Janice E. Williams, Ph.D., M.P.H., lead author of the study conducted at the University of North Carolina at Chapel Hill, says the findings were true for individuals with normal blood pressure levels, but not those with high blood pressure. "The implications of our study are that anger could potentially lead to heart attacks, especially among middle-aged men and women with normal blood pressure."
The researchers say that there has "always been a suspicion that emotional states such as anger, anxiety and depression have an impact on health. Now, we¹re better able to document the association with the use of follow-up studies like this one."
During the six-year study, 256 individuals had heart attacks. Individuals who were the most prone to anger were 2.69 times more likely to have a heart attack or sudden death than those with the lowest anger ratings on a 40-point scale. Individuals who scored moderate were 35 percent more likely to experience a coronary event.
"These findings were also true even after taking into account the presence of risk factors such as smoking, having diabetes, cholesterol levels and excess weight," she says.
The study used a prospective design. In this kind of study design, individuals are free of heart disease at the beginning of the study. Prospective studies provide more convincing evidence than many other types of studies because they show that anger precedes the heart attack and is not a consequence of ill health.
Heart attacks occur when a blood vessel is blocked by a blood clot that forms on a plaque, a collection of fat on the blood vessel. Stress hormones, which constrict blood vessels, may make the plaque more prone to rupture, resulting in a blood clot that blocks the heart artery.
Researchers analyzed data from nearly 13,000 people who were followed for up to six years as part of the Atherosclerosis Risk in Communities (ARIC) study in four locations: Washington County, Md., suburban Minneapolis, Minn., Forsyth County, N.C. and Jackson, Miss.
Anger was measured by a 10-item questionnaire called the Speilberger Trait Anger Scale. Some of the questions asked if the individuals were hot-headed, quick-tempered, or if they felt like hitting someone when they got angry and felt annoyed when not given recognition for doing good work.
Individuals were given a score of 1 to 40 according to their answers to the questions. The average score was 16. About 8 percent of the individuals scored high, 55 percent scored moderate, and 37 percent scored low. Higher scorers were slightly younger, more likely to be men and to have less than a high school education than participants who were moderate or low scorers.
High scorers were also more likely to be smokers and drinkers. Researchers did not find any racial differences in the association between anger and coronary events. "The lack of an increase in heart attacks among individuals who had high blood pressure and high anger could have been due to the fact that high blood pressure alone is associated with heart disease and an anger-prone personality had little further effect," says Williams.
Researchers say stress management may help anger-prone individuals develop better coping skills to deal with their response to anger-provoking situations.
Co-authors include Catherine C. Paton, M.S.P.H.; Ilene C. Siegler, Ph.D., M.P.H.; Marsha L. Eigenbrodt, M.D., M.P.H.; F. Javier Nieto, M.D., Ph.D.; and Herman A. Tyroler, M.D.