Posttraumatic Stress Disorder 

The formal diagnosis of posttraumatic stress disorder (PTSD) was not introduced into the Diagnostic and Statistical Manual of Mental Disorders (DSM) until its third publication, in 1980. In earlier DSM editions, this relatively new diagnosis was characterized as stress response syndrome, a type of gross stress reaction, or a situational disorder, and was often incorrectly associated with personal weakness instead of situational trauma.^[1]

PTSD is now defined as a pathological anxiety that usually occurs after an individual experiences or witnesses severe trauma that constitutes a threat to the physical integrity or life of the individual or of another person.

The individual initially responds with intense fear, helplessness, or horror. The person later develops a response to the event that is characterized by persistently reexperiencing the event, with resultant symptoms of numbness, avoidance, and hyperarousal.^[2] These symptoms result in clinically significant distress or functional impairment. To meet the full criteria for PTSD, these symptoms should be present for a minimum of 1 month following the initial traumatic event.

The events experienced may be natural disasters, violent personal assaults, war, severe automobile accidents, or the diagnosis of a life-threatening condition. For children, a developmentally inappropriate sexual experience may be considered a traumatic event, even though it may not have actually involved violence or physical injury.

Brain structures associated with the body’s reaction to fear and stress can be seen in the image below.

PTSD can be acute (symptoms lasting < 3 mo), chronic (symptoms lasting ≥ 3 mo), or of delayed onset (6 mo elapses from event to symptom onset).

Studies have pointed to a new, dissociative subtype of PTSD, with clinical and neurobiologic features that distinguish it from the nondissociative form. This dissociative subtype is described as an overmodulation of affect, or a form of emotion dysregulation, and is mediated by midline prefrontal inhibition of limbic regions. These findings are important in the treatment of PTSD, because patients can now be assessed for dissociative symptoms and treated accordingly.^[3]

Complications of PTSD

Individuals with PTSD may have an increased risk of impulsive behavior, suicide, and homicide. Victims of sexual assault are at especially high risk for developing mental health problems and committing suicide.

Persons with PTSD may also be at increased risk for panic disorder, agoraphobia, obsessive-compulsive disorder, social phobia, specific phobia, major depressive disorder, and somatization disorder.

One study associated PTSD with a risk of developing dementia among older US male veterans. In a group of male veteran participants, those diagnosed with PTSD were twice as likely to develop dementia as were those without PTSD. Discovering the biological link between these disorders would be a monumental accomplishment in the fight to reduce the occurrence of dementia in PTSD victims.^[4]

The legal system and PTSD

One major reason for litigation in the event of trauma and criminal offenses is to punish persons involved in violence and criminal activity. As a witness to an act of violence, the victim has an obligation to report the crime and to cooperate with law enforcement officials.

This may involve testifying before a grand jury, which occurs before the case formally begins.

The victim acts as a witness to the case and, therefore, is not a party to the criminal proceedings and is not represented. This can be difficult after experiencing the event itself, which characterizes loss of power, control, and dignity.

Victims often require the support and advocacy of legal representation, but the system does not provide it. The prosecuting attorney is the supposed advocate for the victim, but the attorney's job of defending the interests of justice may conflict with the interests of the victim.

The process of a trial can be very traumatic for the victim, particularly in cases of sexual trauma. Defense tactics sometimes involve blaming the victim for the crime by tainting his or her character; this may add more pain to an already painful process.

Go to Anxiety Disorders for more complete information on this topic.

When PTSD occurs, symptoms of PTSD usually begin within 3 months of the traumatic event. However, a delay of months or years may occur before symptoms appear.

Physiologic factors

The amygdala is a key brain structure implicated in PTSD. Research has shown that exposure to traumatic stimuli can lead to fear conditioning, with resultant activation of the amygdala and associated structures, such as the hypothalamus, locus ceruleus, periaqueductal gray, and parabrachial nucleus. This activation and the accompanying autonomic neurotransmitter and endocrine activity produce many of the symptoms of PTSD.

The orbitoprefrontal cortex exerts an inhibiting effect on this activation. The hippocampus also may have a modulating effect on the amygdala. However, in people who develop PTSD, the orbitoprefrontal cortex appears to be less capable of inhibiting this activation, possibly due to stress-induced atrophy of specific nuclei in this region.^{[5, 6]}

Risk factors

As mentioned, PTSD is caused by experiencing, witnessing, or being confronted with an event involving serious injury, death, or threat to the physical integrity of an individual, along with a response involving helplessness and/or intense fear or horror. In various studies, a direct relationship has been observed between the severity of the trauma and the risk of developing PTSD.^[7]

When these events involve an individual with a physiologic vulnerability based on genetic (inherited) contributions and other personal characteristics, PTSD results. These personal characteristics include prior exposure to trauma, childhood adversity (eg, separation from parents), and preexisting anxiety or depression.

One of the most pivotal observations in relation to the development of PTSD in adults who were traumatized as children is the association between early trauma exposure and subsequent retraumatization.^[8]

Researchers have identified factors that interact to influence vulnerability to developing PTSD.^{[9, 10]} These factors include the following:

• Characteristics of the trauma exposure itself
• Characteristics of the individual
• Posttrauma factors

Regarding characteristics of the trauma exposure itself, factors that influence the development of PTSD include the trauma’s proximity and severity, as well as the duration of an individual’s exposure to the trauma

Characteristics of the individual that increase vulnerability to PTSD include prior trauma exposures, family history or prior psychiatric illness, and sex (women are at greatest risk for many of the most common assertive traumas).

Posttrauma factors that influence whether PTSD develops include availability of social support, emergence of avoidance or numbing, hyperarousal, and reexperiencing symptoms.

With regard to reexperiencing symptoms, a pilot monozygotic twin study showed that patients with PTSD have impaired extinction of novel conditioned fear stimuli.^[11]

Combat and PTSD

Approximately 30% of men and women who have spent time in a war zone experience PTSD.^[12]

Studies conducted with veteran participants from Operation Iraqi Freedom and Operation Enduring Freedom (Afghanistan) determined a strong correlation between duration of combat exposure and PTSD. Service members from Operation Enduring Freedom (Afghanistan) reported less combat experience and, consequently, a lower incidence of mental health disorder compared with veterans of Operation Iraqi Freedom, who reported greater combat exposure.^{[13, 14]} A study by Polusney et al suggests that combat-related PTSD is strongly associated with postconcussive symptoms and psychosocial outcomes one year after return from Iraq; however, little evidence of a long-term negative impact due to concussion and mild traumatic brain injury after accounting for PTSD.^[15]

Incidence of PTSD in the United States

PTSD has a lifetime prevalence of 8-10% and accounts for considerable disability and morbidity. One study found the prevalence of PTSD in a sample of adolescent boys to be 3.7% and the prevalence in adolescent girls to be 6.3%.^[16]

Sex preference in PTSD

Females may be at higher risk for PTSD than are males. An epidemiologic survey of adult women indicated alarmingly high rates of traumatic events, particularly events associated with being crime victims. Sexual assault probably has the most impact on women, and trauma from combat probably has the most impact on men.

Although earlier veteran studies were somewhat inconsistent, subsequent studies have suggested that service in Operation Iraqi Freedom presented equal PTSD risk to both sexes, with the duration and severity of combat experience having a greater influence than sex on the likelihood of a veteran having PTSD.^{[17, 18]}

Age preference in PTSD

PTSD can occur in persons of any age, including children.

Prognosis in cases of PTSD is difficult to determine, because it varies significantly from patient to patient. Some individuals who do not receive care gradually recover over a period of years. Many individuals who receive appropriate medical and psychiatric care recover completely (or nearly completely). Rarely, even with intensive intervention, individuals experience worsening symptoms and commit suicide.

In patients with PTSD who are receiving treatment, the average duration of symptoms is 36 months, compared with 64 months for those patients who do not receive treatment. However, more than one third of patients who have PTSD never fully recover.

Factors associated with a good prognosis include rapid engagement of treatment, early and ongoing social support, avoidance of retraumatization, positive premorbid function, and an absence of other psychiatric disorders or substance abuse.

Results from a pilot study in civilians suggested that patients with PTSD who experienced peritraumatic tonic immobility during the traumatic event have a poor response to pharmacologic treatment.^[19]

When a family member is diagnosed with PTSD, the entire family may be affected. Members may experience shock, fear, anger, and pain because of their concern for the victim. Living with family members who have PTSD does not cause PTSD. Yet, it can cause some similar symptoms, such as feelings of alienation from and anger toward the victim. Other family members may find it difficult to communicate with a person with PTSD. Sleep disturbance and abuse (physical and substance) may occur among family members.

Families should engage in counseling if anger, addiction, or problems in school or work become issues. Stress and anger management and couples' therapy are possibilities. Families should try to maintain their outside relationships and should continue to be involved in pleasurable activities.

For patient education information, see eMedicine's Mental Health and Behavior Center, as well as Post-traumatic Stress Disorder (PTSD) and Stress.

The following Web sites also provide valuable information for patients and their families: US Department of Veteran Affairs National Center for PTSD, US Army Office of Behavioral Health, Afterdeployment.org, National Institute of Mental Health, American Academy of Child and Adolescent Psychiatry, and Mayo Clinic.