It's no secret that men with angry, explosive personalities are at a higher risk of a heart attack. But they're not alone: Nervous, withdrawn and chronically worried people are courting coronary problems, too, according to a new long-term study in the Journal of the American College of Cardiology. Of 735 American middle-aged or elderly men who had good cardiovascular health in 1986, those who scored highest on four different scales of anxiety were far more likely to suffer heart attacks later in life. Men in the top 15% on any of the four scales, or on a combined scale of all four, had a 30% to 40% greater chance of heart attack than their less anxious peers.
Researchers have long known that problems of the mind can affect health. Other studies have looked at the relationships between heart-attack risk and factors like "Type A" personality, anger or depression. But "very few studies look at many psychological factors at one time," says Biing-Jiun Shen, lead author on the anxiety paper and an assistant professor of psychology at the University of Southern California. "I think that's a unique part of this study."
Using data from the U.S. Normative Aging Study, Shen reviewed the men's responses to a series of questions on the Minnesota Multiphasic Personality Inventory (a commonly administered personality test), and pulled out their scores on four separate anxiety scales that measured obsessive or compulsive thoughts; introversion and social exclusion; phobias; and a predisposition to become tense or have a physical reaction, like nausea or hyperventilation, to stressful situations. Even after accounting for other mood problems, like depression or anger, and for a whole host of physiological and demographic indicators — including age, body mass index, education, blood pressure, cholesterol levels and smoking and drinking habits — the effect of chronic anxiety was clear. It was also a stronger risk factor for heart attack than any of the other psychological problems in the study.
What's not so clear is why that might be. The relationship between stress, psychological problems and coronary disease or other physical woes is still not well understood. But it is the subject of intense scientific scrutiny. Many other researchers are trying to understand the interaction between mood disturbances like anxiety or depression and other health problems.
Shen notes the results of his study may not be universally applicable across populations. "We only looked at men who are older, around 60," he says. While men may suffer more heart attacks than women, women are far more likely to suffer from anxiety, just as they're more likely to suffer from depression. Gender aside, there's no reason to believe that the link between anxiety and heart attacks is straightforward. "We're not saying depression's not important. We're not saying anger's not important," Shen says. "Different factors can be essentially different for different groups." Still, psychological problems are often related, which means that different problems can affect the body in the same ways. The bottom line is that more study will be needed before we know how much sway our brains have over our heart function — and how much we can control what happens in the mind to prevent a heart attack.