Stress disorder treatable if recognized

Q: After returning from combat in Iraq, my nephew was diagnosed with post-traumatic stress disorder. His symptoms remind me of my problems after a messy divorce, though his experiences were certainly more traumatic. Could I have had PTSD, too?

A: War is one of the leading causes of post-traumatic stress disorder (PTSD). But the severe traumas of everyday life, perhaps even divorce, can trigger the same symptoms. Although no one doubts the seriousness of PTSD, experts have long debated exactly what it is and how to diagnose it.

People have known for thousands of years that terrifying events can have lasting consequences on the psyche. After World War I, the syndrome was called shell shock; after World War II, combat neurosis; and after the Korean War, combat fatigue. In 1980, PTSD got its present name and classification as a specific psychiatric disorder.

The disorder is defined today by three kinds of symptoms:

--Hyperarousal. This includes irritability, startling easily, being constantly on guard, sleeping poorly and having difficulty concentrating.

--Re-experiencing or intrusion. You recall the traumatic event involuntarily through vivid memories, nightmares and flashbacks. You may feel or even act as though it is happening again. Any object, situation or feeling that reminds you of the trauma may cause intense distress.

--Avoidance and emotional numbing. You try to avoid feelings, thoughts, people, places and situations that remind you of the trauma. You lose interest in usual activities and feel disconnected from other people and even from your own feelings.

These three sets of symptoms have a common theme: fixation on the trauma. The traumatic event dominates and controls the lives of people with PTSD. They have not gotten over the event, so they repeatedly re-experience it. .

PTSD is more likely to arise in someone with a history of traumatic experiences. Intentional injury, physical or sexual assault, creates a greater risk of PTSD than a natural disaster or an accident. Victims who feel guilty because they believe that they bear some responsibility for the event are at even greater risk.

Over the years, the American Psychiatric Association's definition of a traumatic experience has focused less on the event itself and more on its effect. Today, a traumatic experience is defined as one that involves a threat of death or serious injury, or provokes mental distress, such as intense fear, helplessness or horror. The victim may experience the event directly, witness it or be confronted with it in some other way, even by just hearing about it.

By these standards, many kinds of events can be deemed traumatic. Some research suggests that people who experience common stressors such as illness, divorce, bereavement or job loss develop such symptoms at the same rate as those who undergo traumatic stress. One study found that more than half of Americans have had such an experience. But most people who have had a traumatic experience do not develop PTSD; only 3 percent of men and 10 percent of women, according to a large German study.

Several factors account for why some people get PTSD and some don't. Women seem to be two to three times as vulnerable to PTSD as men, perhaps due to genetic, hormonal or social reasons. Women tend to suffer different types of trauma than men, such as rape and molestation. The trauma may also be more prolonged, as in the case of a battered wife. Long-term stress can have a more profound effect than a single event.

Brain chemistry might play a role. New Zealand researchers looked at two genes that produce chemicals essential for brain function. They found that abused boys who had changes in one of the genes were more likely to commit violent crimes as adults.

Brain imaging suggests that in patients with PTSD, the hippocampus, a center for storing memories, is smaller than average. Someone born with a larger hippocampus might thus be better equipped to handle a trauma. High IQ may blunt the impact of a traumatic experience, and low IQ may worsen it.

No two people are the same, and neither are their reactions to a trauma. There's no shame in being overwhelmed by a horrible event. If your days and nights are haunted by a scarring event, no matter how long ago it happened, seek help from a mental-health professional. Counseling and medication, if necessary, can offer tremendous relief.

No one is immune to trauma or its emotional aftermath. But PTSD is a treatable disorder; the sooner you recognize it and seek help, the sooner you'll get relief.

The Harvard Medical School Adviser is researched and written by the faculty and staff of Harvard Medical School. Visit www.health.harvard.edu/adviser.