Overview of Post-traumatic Stress Disorder

War-zone related post-traumatic stress disorder (PTSD) is a psychiatric disorder that includes specific distressing symptoms resulting from traumatic exposure to a life threat and/or other highly distressing events during deployment, and results in impairments in work and relationship functioning. To meet diagnostic criteria for PTSD the following seven conditions must be met:

• Exposure to one or more traumatic events during which a person experiences, witnesses or is confronted with actual or threatened death or serious injury, or threat to the physical integrity of self and others.
• At the time of traumatic exposure the person experiences intense levels of terror, horror, or helplessness.
• The traumatic event is persistently reexperienced in one or more of the following ways: recurrent unwanted memories of the event including images, thoughts and perceptions; recurrent distressing dreams of the event; acting or feeling as if the traumatic event were recurring again; intense psychological distress provoked by reminders of the traumatic event; physical reactions when reminded of the event including heart racing, sweating, and rapid breathing. 
• Persistent avoidance of reminders of the event and emotional numbing as indicated by three or more of the following: efforts to avoid thoughts, feelings or conversations associated with the trauma; efforts to avoid activities, places or people that bring back memories of the trauma; difficulty recalling important aspects of the traumatic event; loss of interest or participation in previously significant and enjoyable activities; feeling distant or cut off from other people; trouble experiencing feelings such as love or happiness; and feeling that your future will be cut short.
• Persistent symptoms of increased arousal not present before the traumatic event as indicated by two or more of the following: difficultly falling or staying asleep; irritability or outbursts of anger; difficulty concentrating; being alert or watchful when there's no real need to be; and strong startle reactions.
• These symptoms persist for more than one month. 
• These symptoms result in significant emotional distress, or impairment in social and occupational functioning

In addition to these seven conditions, individuals with post-traumatic stress disorder may also describe painful feelings of guilt for surviving when others died or were more seriously injured; have difficulty regulating their emotions; may be troubled by feelings of shame and hopelessness; see the world as a dangerous, uncontrollable and unpredictable place fraught with future risks;  withdraw from important family and social relationships; may experience a variety of stress related physical problems; and over time if symptoms persist, experience negative changes in personality.

Post-traumatic stress disorder may occur at any age, including during childhood and later life.  The lifetime risk for PTSD in the general American population has been estimated to be 7.8 percent, with 5 percent for men and 10 percent for women.  Risk factors for adult onset PTSD include exposure to traumatic events during childhood and adolescence, family history of anxiety and depression, family history of alcohol and drug abuse, female gender, lower IQ, poorer social supports before and after traumatic exposure, higher levels of stressful life events in the year before and after traumatic exposure, higher levels of terror, horror and helplessness at the time of traumatic exposure, and higher levels of dissociation at the time of traumatic exposure, including feelings that what was happening was not real (as though one were in a movie, dream or a play), feeling distant or detached from the traumatic events as they were occurring, experiencing time moving in slow motion, muffled sounds, and tunnel vision.

In the general American population, the time course for symptom duration is highly variable, with most people developing symptoms in the first month, although delayed onset six months or longer occurs in a minority of cases.  Approximately 50 percent of individuals with civilian PTSD will recover in the first three months.  However, recovery after one year is limited, with half of those with PTSD at one year remaining symptomatic three to five years or longer.

PTSD in Vietnam Veterans

Nearly 25 years ago, in response to unanswered questions concerning Vietnam Veterans’ postwar adjustment, the United States Congress enacted Public Law 98-160, which directed the Veterans Administration to arrange for an independent, scientific study of the adjustment of Vietnam Veterans.  The purpose of this study was to provide an empirical basis for the formulation of policy related to Veterans’ psychosocial health.  In response to congressional mandate, the National Vietnam Veterans Readjustment Study (NVVRS; Kulka, Schlenger, Fairbank, Hough, Jordan, Marmar & Weiss, 1990, Jordan and colleagues, 1991) was conducted.  The survey component of the NVVRS was conducted in 1986-87 with a national probability sample of Veterans who had served in the U.S. Army, Navy, Air Force or Marines between August 5, 1964 and May 7, 1975.  The findings of the survey were presented to Congress in 1988.  Because of its important scientific strengths, including a representative sampling of all who had served in the Vietnam War, and its comprehensive assessment using reliable and valid measures, NVVRS findings have been an important part of the foundation of a federal policy related to war veterans for more than two decades.

Highlights of the Findings of the NVVRS

• As of the time the study was conducted in 1986 and 1987, the majority of Vietnam theater veterans had made a successful reentry into civilian life and were experiencing few symptoms of PTSD or other readjustment problems.
• 15.2 percent of male Vietnam theater veterans met the criteria for current cases of PTSD, representing approximately 479,000 of the estimated 3.14 million men who served in the Vietnam theater.  This compared with rates of 2.5 percent for male Vietnam-era veterans who did not serve in the Vietnam theater.
• Among Vietnam theater veteran women, current PTSD prevalence was estimated to be 8.5 percent of the approximately 7,200 women who served.  This compares with rates of 1.1 percent for female Vietnam era veterans who did not serve in the Vietnam theater.
• Comparisons of current and lifetime prevalence indicated that 49.2 percent of male and 31.6 percent of female theater veterans who had developed PTSD since returning from their war-zone service still had it at the time of their 1986-87 survey interview.
• An additional 11.1 percent of male theater veterans and 7.8 percent of female theater veterans, approximately 350,000 additional men and women, suffered from partial PTSD.
• 30.6 percent of male Vietnam theater veterans and 26.9 percent of female veterans serving in the Vietnam theater met criteria for full PTSD at some time during their lives.  Thus, about half of the men and one third of the women who ever developed war-zone related PTSD had PTSD at the time of the study, a decade or more after the conclusion of the war.
• Vietnam veterans with PTSD have higher rates of other specific psychiatric disorders including depression and alcohol and drug abuse, and a wide variety of other postwar readjustment problems affecting work, family functions and physical health.
• Substantial difference in PTSD prevalence rates were found by minority status.  Prevalence of PTSD was estimated to be 27.9 percent among Hispanics, 20.6 percent among African-Americans, and 13.7 percent among Whites/Others.  The African-American and White/Others differential rates were attributable in part to greater levels of warzone stress exposure for African-Americans.  The differences between Hispanics and the other two groups could not be explained by level of warzone stress exposure.
• Interviews conducted with spouses and partners of Vietnam theater veterans with and without PTSD indicated that PTSD has a substantial negative impact not only on the veterans own lives, but also on the lives of spouses, children, and others living with Vietnam veterans with PTSD.
• At the time the survey was conducted in 1986 and 1987, very substantial proportions of Vietnam veterans with readjustment problems had never used the VA or any other source for their mental health problems, particularly during the 12 months prior to their assessment.

NVVRS Findings on the Impact of PTSD on Military Families

Post-traumatic stress disorder in those who serve in combat may have a profound effect on their relations with their spouses, partners, and children.  As part of the NVVRS, spouses and partners of 376 Vietnam combat veterans were interviewed.  These interviews assessed the spouses’/partners’ views of family and marital adjustment, parenting problems, and interpersonal violence, as well as the spouses’/partners’ view of their own mental health, drug and alcohol problems.  It additionally assessed behavioral problems of school-age children living at home.  Compared with families of male veterans without current PTSD, the families of male veterans with current PTSD showed markedly elevated levels of severe and diffuse problems in marital and family adjustment, parenting skills, and violent behavior.

The spouses/partners of Vietnam theater veterans with PTSD were significantly more likely to report lower levels of happiness and life satisfaction, higher demoralization scores, and higher numbers of alcohol problems. This is true despite the fact that 75 percent to 80 percent of the spouses/partners were currently working, and the majority had worked for most of their relationship with the veteran.  The spouses/partners had about 13 years of education and, overall, the prestige of the spouses’/partners’ occupation did not differ significantly between the PTSD and non-PTSD groups.

 In addition, the children of male Vietnam veterans with PTSD had higher levels of behavioral problems than children of male Vietnam veterans without PTSD.  The NVVRS findings are consistent with other published studies of the impact of combat related PTSD on family functioning.  Across studies, veterans with PTSD are much more likely to report marital, parental, and family adjustment problems than veterans without PTSD.  Children of veterans with PTSD are much more likely to have behavioral problems than children of veterans without PTSD, with more than one-third of all male veterans with PTSD having a child with problems in the clinically significant range.

A primary conclusion of the NVVRS findings of the impact of combat related PTSD in male Vietnam theater veterans on their families is that early treatment for those suffering the effects of combat related PTSD, including family therapy, is essential in preventing symptoms of PTSD and related psychiatric disorders from wreaking havoc on marital and family relationships. 

Military Record Validation of War-zone Exposure and PTSD Rates in the NVVRS

Dohrenwend and colleagues (2006) reanalyzed the prevalence rates of PTSD in the NVVRS.  They used military records to construct a new combat exposure measure that was independent of the veterans’ self-report of their combat exposure and to crosscheck exposure reports and diagnoses of 260 NVVRS veterans.  They found little evidence of falsification of combat exposure, and a very strong relationship between records-based severity of warzone stressor exposure and risk for PTSD.  They did find adjusted PTSD rates lower than the original NVVRS results, with 18.7 percent of the veterans developing war related PTSD at some time after their return from Vietnam and 9.1 percent currently suffering from PTSD 11 to 12 years after the war.  Current PTSD was associated with moderate levels of impairment. 

The PTSD rates reported by Dohrenwend and colleagues can be considered a conservative, lower bound estimate of the true prevalence rates in the Vietnam theater groups.  In particular, they excluded as PTSD cases those veterans with a pre-military diagnosis of PTSD.  This represents a conservative bias given the extensive literature demonstrating that childhood trauma exposure is one of the best established risk factors for adult onset PTSD in both civilian and military studies (Brewin, Andrews and Valentine, 2000).  The decision to exclude those with pre-combat PTSD accounts for about half of the reported prevalence differences from the original NVVRS findings.  By comparison, adjustment for impairment and exposure documentation together account for only 3.8 percentage points of the reduction in lifetime prevalence and 3.1 percentage points of the current prevalence difference.  In other words, half or more of the “reduction” in PTSD prevalence rates is attributable to not counting as cases those veterans who came to Vietnam with one of the most potent risk factors for PTSD.

Imperative Need to Conduct a Long-term Follow-up Study to the NVVRS

The Department of Veterans Affairs (VA) is recognized as an international leader in the study and treatment of PTSD.  The NVVRS was a landmark investigation, providing definitive information about the prevalence and etiology of PTSD and other mental health and readjustment problems. Findings from the NVVRS were an important ingredient in the mix of social and political forces that brought about substantial changes in VA policy towards the postwar readjustment problems of Vietnam veterans and in the public’s understanding and acceptance of the concept of PTSD.  Because of the high rates of PTSD, the strong evidence for the persistence of this syndrome, and the strength of its association with war-zone stress exposure, it is imperative that the VA have information about the current functioning of the participants in the original study. This imperative is heightened by the need to understand the long-term mental and physical health consequences of war-zone related PTSD to inform strategies for preserving resilience and mitigating complications in those serving in Operation Enduring Freedom (OEF) and Operation Iraqi Freedom (OIF).

The November 2000 Public Law 106 - 419 specified that a follow-up study be conducted utilizing the database and sample of the NVVRS study.  The law specified that the study be designed to yield information on the following:

1. the long-term course of post-traumatic stress disorder in Vietnam Veteran
2.  any long-term medical consequences of post-traumatic stress disorder
3. whether particular subgroups of veterans are at greater risk of chronic or more severe problems with such disorder
4. the services used by veterans who have post-traumatic stress disorder and the effect of those services on the course of the disorder.

The proposed follow-up, referred to as the National Vietnam Veterans Longitudinal Study (NVVLS) will address the aims mandated by PL 106-419.  Specifically it will accomplish the following:

• Provide important information about the current functioning of veterans of the Vietnam War, who will be more than 20 years further downstream from their Vietnam experiences than they were at the time of the NVVRS.
• Systematically document long-term course of PTSD and other postwar adjustment problems based on the experiences of a cohort with internal and external validity unmatched in the field. Of particular interest would be new cases of PTSD, recovery or chronicity among prior cases, and the possible impact of VA programs on the course and outcome of PTSD
• The NVVLS provides an unparalleled opportunity to determine if war zone related PTSD is a risk factor for physical health problems.  This concern is highlighted by recent findings:  a study of Iraq and Afghanistan Veterans (Cohen and colleagues, 2009) provided preliminary evidence for an increased risk of cardiovascular disease in those with PTSD, depression and the combination; and a VA database study of middle aged Veterans (Yaffe and colleagues, in press) reported a twofold increase in the 10 year risk for dementia in those with PTSD.  The NVVLS will explore the potential association of PTSD with hypertension, adult onset diabetes, increase blood lipids, premature morbidity and death due to cardiovascular complications and the risk for early onset dementia.  The power to detect these associations is greatest in veterans in their 50s, 60s and early 70s, the current age range of those originally enrolled in the NVVRS.   
• Determine the long-term impact of war zone deployment on the spouses, partners and children of Vietnam veterans with and without PTSD.
• Advance the field’s understanding of the etiology of PTSD in ways that cross-sectional assessments cannot.
• Determine the patterns of mental health care utilization, identify long term barriers to care, determine satisfaction with VA and other mental health services, and identify needs for future health and mental health services for aging Vietnam Veterans.

Combined Mild Traumatic Brain Injuries and PTSD

It has been proposed that the signature wound in the global war on terror is traumatic brain injury.  There are multiple causes of head trauma including blast exposure, gunshot wounds, motor vehicle injury, and other accidents causing concussive injury. These are the same events that are likely to trigger terror, horror and helplessness associated with life threat exposure, creating a double jeopardy in which veterans are simultaneously exposed to the risk for PTSD and concussive head injury.  As noted by Ritchie, the severely wounded are routinely screened for head trauma, however, others who may have been simply knocked unconscious for short periods of time may not present for treatment. 

OEF and OIF veterans who have suffered repeated mild traumatic brain injuries (TBI), including concussions, may have gone undiagnosed in the theater.  The symptoms may only surface later, after the veterans return home.  Given that certain of the symptoms of mild repeated concussive head injury and post-traumatic stress disorder are similar, including concentration difficulties, sleep disruption, and irritability, and given that concussive head injuries are likely to occur in settings of a high war-zone traumatic stress exposure, veterans with dual diagnosis PTSD and TBI will present unique diagnostic and treatment challenges. As one example: cognitive behavioral treatment, the best evidence- based psychosocial treatment for PTSD, depends upon intact cognitive functioning which may be compromised following repeated closed head injuries.  Repeated closed head injuries, particularly in those who are genetically vulnerable, also constitute risk factors for early cognitive decline and dementia. 

The VA’s recent institution of mandatory training in traumatic brain injury for health care professionals is an important step in preparing to better manage the long-term consequences of concussive injuries in the war zone. 

Assessment of TBI was not a focus in the NVVRS.  It will be of great interest to determine the incidence of mild TBI in the NVVLS and how closed head injuries have influenced the course of Vietnam combat related PTSD.

Importance of Conducting the NVVLS for the Readjustment of Iraq and Afghanistan Veterans

An estimated 1.9 million American men and women have served in these conflicts and are at risk for psychiatric problems.  The NVVLS will generate critical knowledge about risk and resilience, course and complications of war-zone related PTSD on veterans and their families over a more than a four decade time frame.  This knowledge has the potential to serve as a blueprint for better preparing for the readjustment needs of those serving in Operation Enduring Freedom (OEF) and Operation Iraqi Freedom (OIF). The urgent need to plan for long-term mental health consequences of OEF and OIF is underscored by the following research findings:

PTSD in OEF and OIF Personnel

Hoge and colleagues (2004, 2006, 2007) have published studies reporting on PTSD and associated psychological problems related to combat duty in Iraq and Afghanistan.  Highlights from those research findings are as follows:

• Exposure to combat was significantly greater among those deployed to Iraq than  Afghanistan.
• Three to four months after their return from combat duty, 15.6 to 17.1 percent of those who were deployed to Iraq met screening criteria for major depression, generalized anxiety disorder, or PTSD.
• In their initial report published in 2004, only 23 to 40 percent of those who screened positive for mental health problems sought mental health care. 
• Those screening positive for mental disorders were twice as likely as those screening negative for mental disorders to report concerns about possible stigmatization and other barriers to seeking mental health care.
• One year after deployment, or at the time of separation from military service if earlier than one year, 19.1 percent of service members returning from Iraq screened positive for mental health problems compared with 11.3 percent  returning from Afghanistan.  Mental health problems were significantly associated with combat experiences, mental health care referral and utilization, and attrition from military service.
• 35 percent of the Iraq war veterans accessed mental health services in the year after returning home.
• Combat experienced soldiers serving in Iraq reported greater physical health complaints relative to soldiers with no prior combat experience. 
• Among battle injured soldiers who served in OEF and OIF, 4.2 percent had probable PTSD at one month, compared with 12.0 percent at seven months post-deployment.  Among battle injured soldiers who served in OEF and OIF, 4.4 percent had probable depression at one month, compared with 9.3 percent at seven months. 
• Among battle injured soldiers who served in OEF and OIF, early severity of physical injuries was strongly associated with later PTSD or depression, with an important delay in the onset for symptoms in a majority of cases.
• In a sample of 2863 soldiers one year after their return from combat duty in Iraq, 16.6 percent met screening criteria for PTSD.  PTSD was significantly associated with lower ratings of general health, more sick call visits, more missed workdays, more physical symptoms, and higher somatic symptom severity.  These results remained significant after controlling for being wounded or injured.
• High prevalence rates of physical health problems among Iraq veterans with PTSD one year after deployment have important implications for delivery of medical services, including the importance of DOD primary care screening of those who present with physical symptoms for combat related PTSD.

Recently Seal and colleagues (in press) investigated longitudinal trends and risk factors for mental health diagnoses among Iraq and Afghanistan veterans. Among 289,328 Iraq and Afghanistan veterans entering Veterans Affairs (VA) health care from 2002 to 2008 using national VA data, 106,726 (36.9 percent) received mental health diagnoses; 62,929 (21.8 percent) were diagnosed with post-traumatic stress disorder (PTSD) and 50,432 (17.4 percent) with depression. Adjusted 2-year prevalence rates of PTSD increased 4 to 7 times after the invasion of Iraq. Active duty veterans younger than 25 years had higher rates of PTSD and alcohol and drug use disorder diagnoses compared with active duty veterans older than 40 years (adjusted relative risk = 2.0 and 4.9, respectively). Women were at a higher risk for depression than were men, but men had over twice the risk for drug use disorders. Greater combat exposure was associated with higher risk for PTSD.

Limitations of Current Studies of Readjustment of OEF and OIF Veterans; Relevance for Conducting the NVVLS

A recent Institute of Medicine (IOM) report notes that the majority of studies of OEF and OIF Veterans have relied on samples of convenience, limiting their external validity, and limiting generalizability to all men and women who have served in active duty, guard and reserve components.  The studies to date have for the most part relied on brief screening instruments to identify key outcomes and to estimate prevalence, which limits internal validity.  The use of cross-sectional designs limits the ability to support causal inference and to elucidate the course of disorders.  The NVVRS, if complimented with the NVVLS, will provide critical lessons learned for anticipating the long-term readjustment needs of OEF and OIF veterans and will inform resource allocation in planning for health care services.  Of note, because the NVVLS will be a longitudinal study of a true probability sample of all who served in Vietnam, it is the only design option which will address all of the internal and external validity concerns raised by the IOM report. 

References:

1990—Kulka RA, Schlenger WE, Fairbank JA, Hough RL, Jordan BK, Marmar CR, Weiss, DS. Trauma and the Vietnam War Generation. New York: Brunner/Mazel.

1990—Jordan BK, Schlenger WE, Hough RL, Kulka RA, Weiss DS, Fairbank JA, Marmar, CM.  Lifetime and current prevalence of specific psychiatric disorders among Vietnam veterans and controls. Archives of  General Psychiatry. 48:207-215

2006—Dohrenwend BP, Turner JB, Turse NA, Adams BG, Koenen KC, Marshall R.  The psychological risks of Vietnam for U.S. Veterans:  a revisit with new data and methods.  Science. 313:979-82

2000—Brewin CR, Andrews B, Valentine JD.  Meta-analysis of risk factors for posttraumatic stress disorder in trauma-exposed adults.  J Consult Clin Psychol. 68:748-66.

2009—Cohen BE, Marmar C, Ren L, Bertenthal D, Seal KH.  Association of cardiovascular risk factors with mental health diagnoses in Iraq and Afghanistan war veterans using VA health care.  JAMA. 302:489-92.

2010—Yaffe K, Vittinghoff E, Lindquist K, Barnes D, Covinsky K, Neylan T, Kluse M, Marmar, C. (in press). Post-Traumatic Stress Disorder and Risk of Dementia among U.S. Veterans. Archives of General Psychiatry.

2004—Hoge CW, Castro CA, Messer SC, McGurk D, Cotting DI, Koffman RL. Combat duty in Iraq and Afghanistan, mental health problems, and barriers to care.  N.  Engl J Med. 2004 Jul 1;351(1):13-22.

2006—Hoge CW, Auchterlonie JL, Milliken CS.  Mental health problems, use of mental health services, and attrition from military service after returning from deployment to Iraq or Afghanistan.  JAMA. 295:1023-32.

2007—Hoge CW, Terhakopian A, Castro CA, Messer SC, Engel CC.

Association of posttraumatic stress disorder with somatic symptoms, health care visits, and absenteeism among Iraq war veterans.  Am J Psychiatry. 164:150-3.

2010—Seal KH, Metzler TJ, Gima KS, Bertenthal D, Maguen S, Marmar CR. (in press).  Trends and risk factors for mental health diagnoses among Iraq and Afghanistan veterans using Department of Veterans Affairs health care, 2002-2008.  Am J Public Health.