Posttraumatic Stress Disorder:
A National Center for PTSD Fact Sheet
Matthew J. Friedman, M.D., Ph.D., Executive
Director, National Center for PTSD
Professor of Psychiatry and Pharmacology, Dartmouth Medical School
A brief history of the PTSD diagnosis
The risk of exposure to trauma has been a part
of the human condition since we evolved as a species. Attacks by saber
tooth tigers or twenty-first century terrorists have probably produced
similar psychological sequelae in the survivors of such violence.
Shakespeare's Henry IV appears to meet many, if not all, of the
diagnostic criteria for Posttraumatic Stress Disorder (PTSD), as have
other heroes and heroines throughout the world's literature. The history
of the development of the PTSD concept is described by Trimble1.
In 1980, the American Psychiatric Association
added PTSD to the third edition of its Diagnostic and Statistical Manual
of Mental Disorders (DSM-III) nosologic classification scheme. Although
controversial when first introduced, the PTSD diagnosis has filled an
important gap in psychiatric theory and practice. From an historical
perspective, the significant change ushered in by the PTSD concept was
the stipulation that the etiological agent was outside the individual
(i.e., a traumatic event) rather than an inherent individual weakness
(i.e., a traumatic neurosis). The key to understanding the scientific
basis and clinical expression of PTSD is the concept of
In its initial DSM-III formulation, a traumatic
event was conceptualized as a catastrophic stressor that was outside the
range of usual human experience. The framers of the original PTSD
diagnosis had in mind events such as war, torture, rape, the Nazi
Holocaust, the atomic bombings of Hiroshima and Nagasaki, natural
disasters (such as earthquakes, hurricanes, and volcano eruptions), and
human-made disasters (such as factory explosions, airplane crashes, and
automobile accidents). They considered traumatic events to be clearly
different from the very painful stressors that constitute the normal
vicissitudes of life such as divorce, failure, rejection, serious
illness, financial reverses, and the like. (By this logic, adverse
psychological responses to such "ordinary stressors" would, in
DSM-III terms, be characterized as Adjustment Disorders rather than
PTSD.) This dichotomization between traumatic and other stressors was
based on the assumption that, although most individuals have the ability
to cope with ordinary stress, their adaptive capacities are likely to be
overwhelmed when confronted by a traumatic stressor.
PTSD is unique among psychiatric diagnoses
because of the great importance placed upon the etiological agent, the
traumatic stressor. In fact, one cannot make a PTSD diagnosis unless the
patient has actually met the "stressor criterion," which means
that he or she has been exposed to an historical event that is
considered traumatic. Clinical experience with the PTSD diagnosis has
shown, however, that there are individual differences regarding the
capacity to cope with catastrophic stress. Therefore, while some people
exposed to traumatic events do not develop PTSD, others go on to develop
the full-blown syndrome. Such observations have prompted the recognition
that trauma, like pain, is not an external phenomenon that can be
completely objectified. Like pain, the traumatic experience is filtered
through cognitive and emotional processes before it can be appraised as
an extreme threat. Because of individual differences in this appraisal
process, different people appear to have different trauma thresholds,
some more protected from and some more vulnerable to developing clinical
symptoms after exposure to extremely stressful situations. Although
there is currently a renewed interest in subjective aspects of traumatic
exposure, it must be emphasized that events such as rape, torture,
genocide, and severe war zone stress are experienced as traumatic events
by nearly everyone.
The DSM-III diagnostic criteria for PTSD were
revised in DSM-III-R (1987), DSM-IV (1994), and DSM-IV-TR (2000). A very
similar syndrome is classified in ICD-10 (The ICD-10 Classification of
Mental and Behavioural Disorders: Clinical Descriptions and Diagnostic
Guidelines). Diagnostic criteria for PTSD include a history of exposure
to a traumatic event and symptoms from each of three symptom clusters:
intrusive recollections, avoidant/numbing symptoms, and hyper-arousal
symptoms. A fifth criterion concerns duration of symptoms. One important
finding, which was not apparent when PTSD was first proposed as a
diagnosis in 1980, is that it is relatively common. Recent data from the
national comorbidity survey indicates PTSD prevalence rates are 5% and
10% respectively among American men and women2.
Rates of PTSD are much higher in postconflict settings such as Algeria
(37%), Cambodia (28%), Ethiopia (16%), and Gaza (18%)3.
Criteria for a PTSD diagnosis
As noted above, the "A" stressor
criterion specifies that a person has been exposed to a catastrophic
event involving actual or threatened death or injury, or a threat to the
physical integrity of him/herself or others. During this traumatic
exposure, the survivor's subjective response was marked by intense fear,
helplessness, or horror.
The "B", or intrusive recollection,
criterion includes symptoms that are perhaps the most distinctive and
readily identifiable symptoms of PTSD. For individuals with PTSD, the
traumatic event remains, sometimes for decades or a lifetime, a
dominating psychological experience that retains its power to evoke
panic, terror, dread, grief, or despair. These emotions manifest in
daytime fantasies, traumatic nightmares, and psychotic reenactments
known as PTSD flashbacks. Furthermore, trauma-related stimuli that
trigger recollections of the original event have the power to evoke
mental images, emotional responses, and psychological reactions
associated with the trauma. Researchers can use this phenomenon to
reproduce PTSD symptoms in the laboratory by exposing affected
individuals to auditory or visual trauma-related stimuli4.
The "C", or avoidant/numbing,
criterion consists of symptoms that reflect behavioral, cognitive, or
emotional strategies PTSD patients use in an attempt to reduce the
likelihood that they will expose themselves to trauma-related stimuli.
PTSD patients also use these strategies in an attempt to minimize the
intensity of their psychological response if they are exposed to such
stimuli. Behavioral strategies include avoiding any situation in which
they perceive a risk of confronting trauma-related stimuli. In its
extreme manifestation, avoidant behavior may superficially resemble
agoraphobia because the PTSD individual is afraid to leave the house for
fear of confronting reminders of the traumatic event(s). Dissociation
and psychogenic amnesia are included among the avoidant/numbing symptoms
and involve the individuals cutting off the conscious experience of
trauma-based memories and feelings. Finally, since individuals with PTSD
cannot tolerate strong emotions, especially those associated with the
traumatic experience, they separate the cognitive from the emotional
aspects of psychological experience and perceive only the former. Such
"psychic numbing" is an emotional anesthesia that makes it
extremely difficult for people with PTSD to participate in meaningful
Symptoms included in the "D", or
hyper-arousal, criterion most closely resemble those seen in panic and
generalized anxiety disorders. While symptoms such as insomnia and
irritability are generic anxiety symptoms, hyper-vigilance and startle
are more characteristic of PTSD. The hyper-vigilance in PTSD may
sometimes become so intense as to appear like frank paranoia. The
startle response has a unique neurobiological substrate and may actually
be the most pathognomonic PTSD symptom.
The "E", or duration, criterion
specifies how long symptoms must persist in order to qualify for the
(chronic or delayed) PTSD diagnosis. In DSM-III, the mandatory duration
was six months. In DSM-III-R, the duration was shortened to one month,
which it has remained.
The "F", or functional significance,
criterion specifies that the survivor must experience significant
social, occupational, or other distress as a result of these symptoms.
Since 1980, there has been a great deal of
attention devoted to the development of instruments for assessing PTSD.
Keane and associates4,
working with Vietnam war-zone veterans, have developed both psychometric
and psychophysiologic assessment techniques that have proven to be both
valid and reliable. Other investigators have modified such assessment
instruments and used them with natural disaster victims, rape/incest
survivors, and other traumatized individuals. These assessment
techniques have been used in the epidemiological studies mentioned above
and in other research protocols.
Neurobiological research indicates that PTSD
may be associated with stable neurobiologicalalterations in both the
central and autonomic nervous systems. Psychophysiological alterations
associated with PTSD include hyper-arousal of the sympathetic nervous
system, increased sensitivity and augmentation of the acoustic-startle
eye blink reflex, a reducer pattern of auditory evoked cortical
potentials, and sleep abnormalities. Neuropharmacologic and
neuroendocrine abnormalities have been detected in most brain mechanisms
that have evolved for coping, adaptation, and preservation of the
species. These include the noradrenergic, hypothalamic-pituitary-adrenocortical,
serotonergic, glutamatergic, thyroid, endogenous opioid, and other
systems. This information is reviewed extensively elsewhere5.
Longitudinal research has shown that PTSD can
become a chronic psychiatric disorder and can persist for decades and
sometimes for a lifetime. Patients with chronic PTSD often exhibit a
longitudinal course marked by remissions and relapses. There is also a
delayed variant of PTSD in which individuals exposed to a traumatic
event do not exhibit the PTSD syndrome until months or years afterward.
Usually, the immediate precipitant is a situation that resembles the
original trauma in a significant way (for example, a war veteran whose
child is deployed to a war zone or a rape survivor who is sexually
harassed or assaulted years later).
If an individual meets diagnostic criteria for
PTSD, it is likely that he or she will meet DSM-IV-TR criteria for one
or more additional diagnoses6,7.
Most often, these comorbid diagnoses include major affective disorders,
dysthymia, alcohol or substance abuse disorders, anxiety disorders, or
personality disorders. There is a legitimate question whether the high
rate of diagnostic comorbidity seen with PTSD is an artifact of our
current decision-making rules for the PTSD diagnosis since there are not
exclusionary criteria in DSM-III-R. In any case, high rates of
comorbidity complicate treatment decisions concerning patients with PTSD
since the clinician must decide whether to treat the comorbid disorders
concurrently or sequentially.
Although PTSD continues to be classified as an
Anxiety Disorder, areas of disagreement about its nosology and
phenomenology remain. Questions about the syndrome itself include: what
is the clinical course of untreated PTSD; are there different subtypes
of PTSD; what is the distinction between traumatic simple phobia and
PTSD; and what is the clinical phenomenology of prolonged and repeated
trauma? With regard to the latter, Herman8
has argued that the current PTSD formulation fails to characterize the
major symptoms of PTSD commonly seen in victims of prolonged, repeated
interpersonal violence such as domestic or sexual abuse and political
torture. She has proposed an alternative diagnostic formulation that
emphasizes multiple symptoms, excessive somatization, dissociation,
changes in affect, pathological changes in relationships, and
pathological changes in identity.
PTSD has also been criticized from the
perspective of cross-cultural psychology and medical anthropology,
especially with respect to refugees, asylum seekers, and political
torture victims from non-Western regions. Clinicians and researchers
working with such survivors argue that since PTSD has usually been
diagnosed by clinicians from Western industrialized nations working with
patients from a similar background, the diagnosis does not accurately
reflect the clinical picture of traumatized individuals from non-Western
traditional societies and cultures. Major gaps remain in our
understanding of the effects of ethnicity and culture on the clinical
phenomenology of posttraumatic syndromes. We have only just begun to
apply vigorous ethnocultural research strategies to delineate possible
differences between Western and non-Western societies regarding the
psychological impact of traumatic exposure and the clinical
manifestations of such exposure9.
Treatment for PTSD
The many therapeutic approaches offered to PTSD
patients are presented in Foa, Keane, and Friedman's10
comprehensive book on treatment. The most successful interventions are
cognitive-behavioral therapy (CBT) and medication. Excellent results
have been obtained with some CBT combinations of exposure therapy and
cognitive restructuring, especially with female victims of childhood or
adult sexual trauma. Sertraline (Zoloft) and paroxetine (Paxil) are
selective serotonin reuptake inhibitors (SSRI) that are the first
medications to have received FDA approval as indicated treatments for
PTSD. Success has also been reported with Eye Movement Desensitization
and Reprocessing (EMDR), although rigorous scientific data are lacking
and it is unclear whether this approach is as effective as CBT.
Perhaps the best therapeutic option for mildly
to moderately affected PTSD patients is group therapy. In such a
setting, the PTSD patient can discuss traumatic memories, PTSD symptoms,
and functional deficits with others who have had similar experiences.
This approach has been most successful with war veterans, rape/incest
victims, and natural disaster survivors. It is important that
therapeutic goals be realistic because, in some cases, PTSD is a chronic
and severely debilitating psychiatric disorder that is refractory to
current available treatments. The hope remains, however, that our
growing knowledge about PTSD will enable us to design interventions that
are more effective for all patients afflicted with this disorder.
There is great interest in rapid interventions
for acutely traumatized individuals, especially with respect to civilian
disasters, military deployments, and emergency personnel (medical
personnel, police, and firefighters). This has become a major policy and
public health issue since the massive traumatization caused by the
September 11 terrorist attacks on the World Trade Center. Currently,
there is controversy about which interventions work best during the
immediate aftermath of a trauma. Research on critical incident stress
debriefing (CISD), an intervention used widely, has brought
disappointing results with respect to its efficacy to attenuate
posttraumatic distress or to forestall the later development of PTSD.
Promising results have been shown with brief cognitive-behavioral
Further information on PTSD is readily
accessible through this website.
Related Fact Sheets
Provides brief information about how PTSD is
Information on availble treatments for PTSD
M.D. (1985). Post-traumatic Stress Disorder: History of a concept. In
C.R. Figley (Ed.), Trauma and its wake: The study and treatment of
Post-Traumatic Stress Disorder. New York: Brunner/Mazel. Revised
from Encyclopedia of Psychology, R. Corsini, Ed. (New York: Wiley, 1984,
R.C., Sonnega, A., Bromet, E., Hughes, M. & Nelson, C.B. (1996).
Posttraumatic Stress Disorder in the National Comorbidity Survey. Archives
of General Psychiatry, 52, 1048-1060.
Jong, J., Komproe, T.V.M., Ivan, H., von Ommeren, M., El Masri, M.,
Araya, M., Khaled, N., van de Put, W., & Somasundarem, D.J. (2001).
Lifetime events and Posttraumatic Stress Disorder in 4 postconflict
settings. Journal of the American Medical Association, 286 (5),
T.M., Wolfe, J., & Taylor, K.I. (1987). Post-traumatic Stress
Disorder: Evidence for diagnostic validity and methods of psychological
assessment. Journal of Clinical Psychology, 43, 32-43.
M.J., Charney, D.S. & Deutch, A.Y. (1995) Neurobiological and
clinical consequences of stress: From normal adaptation to PTSD.
R.A., Schlenger, W.E., Fairbank, J.A., Hough, R.L., Jordan, B.K., Marmar,
C.R., & Weiss, D.S. (1990). Trauma and the Vietnam War
generation. New York: Brunner/Mazel.
J.R.T., & Foa, E.B (Eds.). (1993). Posttraumatic Stress Disorder:
DSM-IV and beyond. Washington, DC: American Psychiatric Press.
J.L. (1992). Trauma and recovery. New York: Basic Books.
A.J., Friedman, M.J., Gerrity, E. & Scurfield R.M. (Eds.). (1996). Ethnocultural
aspects of Post-Traumatic Stress Disorders: Issues, research and
applications. Washington, DC: American Psychological Association.
E.B., Keane, T.M., & Friedman, M.J. (2000). Effective treatments
for PTSD: Practice guidelines from the International Society for
Traumatic Stress Studies. New York: Guilford Publications.
DSM-IV-TR criteria for PTSD
A. The person has been exposed to a traumatic
event in which both of the following have been present:
1. the person has experienced, witnessed, or
been confronted with an event or events that involve actual or
threatened death or serious injury, or a threat to the physical
integrity of oneself or others.
2. the person's response involved intense fear,
helplessness, or horror. Note: in children, it may be expressed instead
by disorganized or agitated behavior.
B. The traumatic event is persistently
re-experienced in at least one of the following ways:
1. recurrent and intrusive distressing
recollections of the event, including images, thoughts, or perceptions.
Note: in young children, repetitive play may occur in which themes or
aspects of the trauma are expressed.
2. recurrent distressing dreams of the event.
Note: in children, there may be frightening dreams without recognizable
3. acting or feeling as if the traumatic event
were recurring (includes a sense of reliving the experience, illusions,
hallucinations, and dissociative flashback episodes, including those
that occur upon awakening or when intoxicated). Note: in children,
trauma-specific reenactment may occur.
4. intense psychological distress at exposure
to internal or external cues that symbolize or resemble an aspect of the
5. physiologic reactivity upon exposure to
internal or external cues that symbolize or resemble an aspect of the
C. Persistent avoidance of stimuli associated
with the trauma and numbing of general responsiveness (not present
before the trauma), as indicated by at least three of the following:
1. efforts to avoid thoughts, feelings, or
conversations associated with the trauma
2. efforts to avoid activities, places, or
people that arouse recollections of the trauma
3. inability to recall an important aspect of
4. markedly diminished interest or
participation in significant activities
5. feeling of detachment or estrangement from
6. restricted range of affect (e.g., unable to
have loving feelings)
7. sense of foreshortened future (e.g., does
not expect to have a career, marriage, children, or a normal life span)
D. Persistent symptoms of increasing arousal
(not present before the trauma), indicated by at least two of the
1. difficulty falling or staying asleep
2. irritability or outbursts of anger
3. difficulty concentrating
5. exaggerated startle response
E. Duration of the disturbance (symptoms in B,
C, and D) is more than one month.
F. The disturbance causes clinically
significant distress or impairment in social, occupational, or other
important areas of functioning.
Specify if: Acute: if duration of
symptoms is less than three months
Chronic: if duration of symptoms is
three months or more
Specify if: Without delay onset: onset
of symptoms at least six months after the stressor