Angry and aggressive people are at risk of suffering heart attack and stroke, researchers have warned.
A new study by the US National Institute on Ageing has analysed 5,614 Italians in four villages and found that those who scored high for antagonistic traits on a personality test had greater thickening of the neck arteries compared to people who were more agreeable.
Thickness of neck artery (carotid) walls is a risk factor for heart attack and stroke, the researchers say.
Three years later, those who scored higher on antagonism or low agreeableness -- especially those who were manipulative and quick to express anger -- continued to have thickening of their artery walls. These traits also predicted greater progression of arterial thickening.
Those who scored in the bottom 10 per cent of agreeableness and were the most antagonistic had about a 40 per cent increased risk for elevated intima-media thickness, a measure of arterial wall thickness.
The effect on artery walls was similar to having metabolic syndrome -- a known risk factor for cardiovascular disease, the study found.
“People who tend to be competitive and more willing to fight for their own self interest have thicker arterial walls, which is a risk factor for cardiovascular disease,” said lead researcher Angelina Sutin.
She added: “Agreeable people tend to be trusting, straightforward and show concern for others, while people who score high on antagonism tend to be distrustful, skeptical and at the extreme cynical, manipulative, self-centered, arrogant and quick to express anger.”
In fact, the study, conducted in the Sardinia region of Italy, included participants aged from 14 to 94 years and 58 per cent were female.
They answered a standard personality questionnaire, which included six facets of agreeableness -- trust, straightforwardness, altruism, compliance, modesty and tender mindedness.
Researchers used ultrasound to determine the intima-media thickness of the carotid arteries in the neck at five points. Participants also were screened for other risk factors for cardiovascular disease like high blood pressure, cholesterol levels, triglycerides and diabetes.
In general, men had more thickening of the artery walls. But if women were antagonistic, their risk quickly caught up with the men, Sutin said.
“Women who scored high on antagonism related traits tended to close the gap, developing arterial thickness similar to antagonistic men. Whereas women with agreeable traits had much thinner arterial walls than men with agreeable traits, antagonism had a much stronger association with arterial thickness in women,” she said.
Though thickening of the artery walls is a sign of age, young people with antagonistic traits already had thickening of the artery wall, she said. “People may learn to control their anger and learn ways to express anger in more socially acceptable ways.”