CHICAGO (Reuters) - People who experience the anxiety, racing heartbeat and rapid breathing of a panic attack have a higher risk of a heart attack or stroke, researchers said on Monday.

"Our study adds panic attacks to the list of emotional states and psychiatric symptoms that have been linked to excess risk of cardiovascular disease and death," wrote study author Dr. Jordan Smoller of Massachusetts General Hospital in Boston.

Previous research found people with persistent feelings of depression, anger and hostility are at higher risk of heart attack, according to the study, published in the Archives of General Psychiatry.

The study identified a more than three-fold increased risk of a heart attack or stroke within five years in 330 women who had originally reported a panic attack in the prior six months. They were among 3,369 women aged 51 to 83 to participate in the study.

Smoller said several factors may be at work, including that the symptoms of panic attacks inflict damage on the heart and the cardiovascular system.

Feelings of panic could induce blood platelet production that increases the risk of a blood clot, which can trigger a heart attack or stroke. Panic attacks also may lead to a spasm of an artery feeding the heart, which can reduce or cut off blood flow, he added.