In an astonishing new study, researchers found that two intense emotions - anger and anxiety - are linked to an increased risk of heart attack.

Specifically, in the two hours following a burst of intense anger the risk of a heart attack rises 8.5 times, compared to 9.5 times after an anxiety attack.

"Our findings confirm what has been suggested in prior studies and anecdotal evidence, even in films - that episodes of intense anger can act as a trigger for a heart attack," lead author Dr. Thomas Buckley, at The University of Sydney, said in a statement. "The data shows that the higher risk of a heart attack isn't necessarily just while you're angry - it lasts for two hours after the outburst."

In the study, intense anger was classified in the study as at 5 or above on a scale of 1 to 7, ranging from "very angry, body tense, clenching fists or teeth, ready to burst," to "enraged, out of control, throwing objects." And these outbursts were reportedly caused by arguments with family members (29 percent), arguments with others (42 percent), work anger (14 percent) and driving anger (14 percent).

What's more, while anger does increase your risk of a heart attack, the findings suggest the effect of an anxiety attack is even more pronounced.

"Increased risk following intense anger or anxiety is most likely due to increased heart rate, blood pressure, tightening of blood vessels and increased clotting, all associated with triggering heart attacks," Buckley said.

The researchers do note that there is only a two percent chance that an angry outburst will actually cause a heart attack; however, for the study participants they were 8.5 times more likely to have a heart attack within two hours of an emotional episode. This means that while the absolute risk of any one episode triggering a heart attack is low, this data indicates that there is still a danger.

"Potential preventive approaches may be stress reduction training to reduce the frequency and intensity of episodes of anger, or avoiding activities that usually prompt such intense reactions, for instance, avoiding an angry confrontation or activity that provokes intense anxiety," added researcher Geoffrey Tofler. "Additionally, improving general health by minimizing other risk factors, such as hypertension, high cholesterol or smoking would also lower risk."

The results were published in the European Heart Journal: Acute Cardiovascular Care.

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