Post Traumatic Stress Disorder - Types Of Anxiety Disorders: Anxiety Disorder

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Post-traumatic stress disorder

The experience: In the weeks following the terrorist attack that destroyed the World Trade Center, a 43-year-old firefighter who helped in the rescue effort is in a state of shock. He can't sleep at night, and during the day, he is preoccupied with horrific images. After he is reassigned to another part of the city, his distress abates somewhat and his memory of that event fades over time. When he tries to remember certain details, they are vague or seemingly forgotten. But even after several months, he still has trouble falling asleep and is often awakened by nightmares about the attack. At home, he's withdrawn from his wife and children. He goes to his primary care physician because he just doesn't feel well. The doctor tells him that he has symptoms of post-traumatic stress disorder (PTSD) and refers him to a psychiatrist.

Symptoms: Symptoms fall into three categories: reliving the event, avoidance, and hyperarousal. An individual may relive the event through flashbacks, dreams, or intrusive thoughts. Avoidance often comes in the form of withdrawing from people or certain situations, or having difficulty remembering important aspects of the trauma. Common symptoms of hyperarousal include having trouble sleeping, being unusually vigilant, and startling easily. The symptoms must last more than a month to be considered signs of PTSD. Symptoms that fade within a month of a traumatic event are signs of acute stress disorder. PTSD has three forms:

1. acute, in which symptoms last one to three months after the trauma

2. chronic, in which the symptoms last three months or more

3. delayed onset, in which at least six months pass between the traumatic event and the start of symptoms.

Experts differ in their views on the nature and severity of events that produce PTSD. Some argue that the event responsible must be extreme, such as being raped or witnessing a murder, while others say that a more ordinary frightening event, such as a car accident, an illness, or a problem at work or in a personal relationship, may also cause PTSD if it induces intense fear, helplessness, and horror (see "Traumas most likely to produce post-traumatic stress disorder," below).

Cause: Because not everyone who lives through a traumatic event develops PTSD, it's likely that biological factors increase the risk. The disorder tends to affect certain families more than others, so there may be a genetic predisposition. Someone who has had depression or who has a first-degree relative (such as a parent, sister, brother, or child) who's had depression is more likely to develop PTSD. For example, a study of 81 rape survivors found that those with family members with depression were more likely to develop PTSD than those whose family members did not have depression. One theory is that people with PTSD have an abnormally strong response to stress, and that excess emotional stress reduces the size of the hippocampus, the part of the brain that oversees memories. Preliminary research has shown that the hippocampus is smaller than normal in people with PTSD. This might be why people with PTSD have memory problems.

Traumas most likely to produce post-traumatic stress disorder Anyone who witnessed the 9/11 terrorist attacks or saw the coverage in the media knows the horror, fear, and sense of helplessness that can accompany a traumatic event. While not everyone affected by trauma goes on to develop post-traumatic stress disorder (PTSD), some do. In October and November of 2001, researchers found that 7.5% of adults living in Manhattan below 110th Street had the disorder, although the prevalence had dropped to 1.7% six months after the disaster. While PTSD is much more likely to affect people who have firsthand, rather than indirect, involvement in a trauma, witnessing such events can reawaken symptoms in people previously traumatized. Even those with no prior experience of PTSD can develop it by witnessing a violent injury or death, or by finding out that a loved one has been involved in such an event. Traumatic event/rate of PTSD in survivors, by gender Some kinds of trauma are especially likely to trigger PTSD. For example, violent acts such as rape lead to PTSD more often than car accidents, fires, and earthquakes. And the same kind of experience may affect men and women differently. As the accompanying graph illustrates, women are more likely to develop PTSD after being physically assaulted, while men are more apt to struggle with it after witnessing a death or injury. Traumas, by their nature, send shock waves through the lives of those affected. While it can be difficult to recover, most people do. Various treatments are available to help individuals overcome the aftereffects of devastating personal tragedies (see "Effective treatments").

Prevalence: An estimated 3.5% of Americans have PTSD, and approximately 10%–14% of women and 5%–6% of men will have it at some point in their lives. Among people who experience traumatic events, its incidence varies according to the event. The highest rates — between one-third and half — are found among survivors of rape, military combat or captivity, and ethnically or politically motivated imprisonment or genocide.

Who's at risk: Among people who experience a traumatic event, the risk for PTSD is especially high among those with a family history of depression (see "Do you have post-traumatic stress disorder?").

Effective treatments: SSRIs, cognitive behavioral therapy, and exposure therapy (see "Specific phobia") are usually helpful. Group therapy can be helpful if the trauma affected several people or more. For example, survivors of an earthquake or a terrorist attack may benefit from discussing the event in a group setting. Benzodiazepines are not recommended, unless you have severe anxiety, in which case short-term use may be helpful. Some studies have found that they are not effective for PTSD. People with PTSD are also at greater risk for substance abuse (to get relief from the intense anxiety), and benzodiazepines can cause physical dependence.

One technique that has not proved effective is a practice known as critical incident stress debriefing, which originated in the military and has been used on firefighters, police officers, and emergency medical technicians, as well as immediate survivors of traumatic experiences. In this approach, participants meet within days of a traumatic experience for a single session lasting for several hours, recounting the event and discussing their thoughts and feelings about it with a counselor. Controlled trials have found that debriefing is not helpful and may even make natural recovery from stress reactions more difficult. Possibly people who are told to probe their feelings at such an early stage feel overwhelmed and misinterpret later symptoms as more serious than they are. It's now generally agreed that no one should be pressured or ordered to participate in critical incident stress debriefing.

Last updated:	September 05, 2008