People who suffer recurring panic attacks are 18 times more likely than people with no mental disorders to try to kill themselves, suggesting that this often neglected disorder may be a major contributing cause of suicides, according to a study.

The researchers said their work should encourage emergency room doctors and other physicians who see people during panic attacks to offer treatment for the disorder.

Victims often seek help for heart attacks, choking and other medical emergencies that mimic the symptoms of panic attack. These people are often told "it's all in their head," rather than being referred to psychiatrists.

The latest finding that panic attacks are strongly linked to suicide attempts points to a potentially serious complication of a common disorder that has been relatively neglected.

An estimated 5 million Americans have panic disorder, recurring bouts of intense fear that strike for no apparent reasons. Two to three times this many people have occasional panic attacks.

The latest study, based on a large survey, found that 20 percent of people with panic disorder had attempted suicide, as had 12 percent of those with occasional panic attacks.

The researchers said that people plagued by panic attacks often think they are going crazy or dying. Many turn to alcohol, become afraid to leave their homes or grow depressed.

"We hope this alerts the non psychiatric physician to the potential mortality and morbidity of panic disorder," said a member of the research teams who's a psychiatric epidemiologist. "If a patient comes into the cardiac clinic

and has panic disorder, and heart attack is ruled out, we would like the physician to realize that the patient should be evaluated for panic disorder."

Just why people with panic attacks are unusually prone to suicide is unclear. Some believe that depression may play a role, although it does not entirely explain the increased risk.

People who have panic attacks for many years become demoralized. They stay at home and withdraw socially and become depressed. We know that depressive feelings are associated with suicide.

The findings are quite remarkable and deserve widespread attention because they may provide general physicians with new opportunities to prevent suicide by recognizing and treating panic disorder.

When experiencing panic attack symptoms, people are gripped by sudden, unpredictable waves of intense apprehension or fear. They may suffer a variety of symptoms, including difficulty breathing,

palpitations, chest pain, choking, dizziness, faintness, trembling and hot and cold flashes, among other sensations.

Panic attacks can be controlled with medical treatment and behavioural therapy. Some people, however, simply try to live with their episodes of terror. Many patients with panic disorder are fine, upstanding people who do not want to

be considered flakey. So they tend to white knuckle through their panic attacks.

Many times, they work very hard to control the symptoms, but internally they are in a great deal of distress. The underlying cause of panic disorder symptoms is not known. The problem runs in families, and experts believe genetic factors may be involved.

People with panic disorder were at times more likely than those with no mental illnesses to try to kill themselves. And they were twice as likely as those with other mental disorders to attempt suicide. The suicide risk grows as the number of panic attacks increase. It is also higher for those who have their first attacks at early ages.