Post-traumatic stress disorder (PTSD) is a mental health condition marked by severe anxiety, flashbacks and uncontrollable thoughts about a terrifying event. Although the disorder is typically associated with soldiers who have been in military combat, PTSD can occur after any event that causes fear and stress.
In the United States, about 60 percent of men and 50 percent of women experience at least one traumatic event in their lives, according to the National Center for PTSD, which is part of the U.S. Department of Veterans Affairs. However, only a small portion of these people — about 5 percent of men and 10 percent of women — will develop PTSD sometime in their lives. The National Institute of Mental Health says PTSD affects about 7.7 million Americans.
It can be difficult to determine whether PTSD cases have increased from years past or if the disorder has just been diagnosed more frequently, as the definition has evolved. "Similar syndromes were called things like 'shell shock' in past wars," said Dr. Paul Schulz, associate professor of neurology at the University of Texas Health Science Center at Houston and the Mischer Neuroscience Institute. "As a result of changes in definitions, and the very recent recognition of PTSD, it is difficult to determine whether PTSD is getting more common or [if] we are simply recognizing it more often."
Symptoms of PTSD
Post-traumatic stress disorder symptoms typically surface within three months of a traumatic event; however, in some people, they may not appear until years after the event, according to the Mayo Clinic.
The National Institute of Mental Health notes that PTSD symptoms are generally grouped into three types:
- Re-experiencing symptoms
- Avoidance symptoms
- Hyperarousal symptoms
Re-experiencing symptoms include those that people typically associate with the disorder: flashbacks, or reliving the event, with physical reactions such as sweating and a racing heart; nightmares; and frightening thoughts. These symptoms can intrude on a person's everyday life. People, places and activities can remind the person of the event and trigger the reactions.
Avoidance symptoms include trying to avoid thinking or talking about the event. People with PTSD will often steer clear of places, events or situations that remind them of the experience for fear of having a flashback and being unable to control their actions. They may also feel emotionally numb.
Hyperarousal symptoms include feelings of stress, and being "on edge" and easily startled. These symptoms are usually constant rather than being triggered by reminders of the event. These symptoms may make it hard to eat, sleep or concentrate.
The NIMH notes that for PTSD to be clinically diagnosed, a person must have at a least one re-experiencing symptom, three avoidance symptoms and two hyperarousal symptoms over the course of a month.
Causes of PTSD
As with many mental health issues, the reasons that some people develop PTSD, and others who experience the same or similar trauma do not, are complex.
An increasing number of scientists are researching the role that genes play in how people react to and form memories of fearful events. For example, PTSD research has focused on stathmin, a protein needed to form fear memories. In a 2005 study published in the journal Cell, researchers at Rutgers University found that mice with a higher level of stathmin were more likely than normal mice to have an exaggerated response after exposure to a fearful experience.
According to the NIMH, a lack of gastrin-releasing peptide (GRP), a signaling chemical in the brain released during emotional events, can cause some people to form greater and more lasting fear memories. Researchers have also found a version of the 5-HTTLPR gene — which controls levels of serotonin, a brain chemical related to mood — that appears to fuel the fear response.
A family or personal history of mental health risks, such as an increased risk of anxiety and depression, can affect the likelihood of experiencing a PTSD episode. Another factor is the way that the brain regulates the chemicals and hormones that the body produces in response to stress. Temperament also plays a role, according to the NIMH.
Children can exhibit different symptoms than adults do. Some children who are suffering from PTSD will regress, sometimes wetting the bed or being unable to talk, according to the American Academy of Child and Adolescent Psychiatry, although they had mastered these tasks prior to the event.
People with PTSD often show differences in certain brain areas compared to healthy people. According to a new model in the July 2013 issue of the journal Trends in Cognitive Sciences, changes in two brain areas — the amygdala and the dorsal anterior cingulate cortex (dACC) — may predispose people to PTSD.
PTSD is typically treated with a combination of counseling and medications.
"Medication is a very common treatment for PTSD but not necessarily the most effective for all patients," said Jim Jeannette, a social worker who practices in Windsor, Ontario. "Most people end up on medication because when they finally realize that they need help, they don't call a counselor; they call their doctor. Doctors usually prescribe, not counsel."
Psychotherapy, which can take place individually or in a group setting, can last six to 12 weeks, Jeannette said. Family, friends and sometimes co-workers can be brought in to help understand the person's behavior and its effect on various aspects of their lives.
For some people with PTSD, exposure with reprocessing is an effective treatment. "The basic principle is that the person is exposed to the memory of the event in a safe and supportive environment and then has the opportunity to reprocess the experience," said Nathaniel Wade, a professor of psychology and director of training in the counseling psychology program at Iowa State University, and director of Network Community Counseling Services. "This allows the traumatic experience to 'move' from being an active, highly charged memory to being something that is no longer activating, or less activating."
For patients who have PTSD coupled with depression or anxiety, cognitive behavior therapy (CBT), in which the person confronts his or her fears directly, is a common and effective treatment, Jeannette said.
Medications such as sertraline (Zoloft) and paroxetine (Paxil) are sometimes prescribed as part of the treatment for PTSD, according to the Mayo Clinic. These medications are antidepressants that can help control sadness, anxiety and anger. Anti-anxiety medications can help relieve feelings of stress and anxiety, but they are only prescribed for a short time because they have the potential for abuse, according to the Mayo Clinic. Sleep aids, antipsychotics and other antidepressants may also be prescribed.
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Kim Ann Zimmermann is a contributor to Live Science and sister site Space.com, writing mainly evergreen reference articles that provide background on myriad scientific topics, from astronauts to climate, and from culture to medicine. Her work can also be found in Business News Daily and KM World. She holds a bachelor’s degree in communications from Glassboro State College (now known as Rowan University) in New Jersey.