SUMMARY OF FINDINGS FROM PREVIOUS CONFLICTS
Any comprehensive assessment of the mental and physical health and other readjustment needs of those deployed in Operation Enduring Freedom (OEF) or Operation Iraqi Freedom (OIF) and their families necessarily takes place in a historical context based on conflicts of the past. There is a long history of both public policy and scientific concern with regard to the effects of military service on individual health and well-being (Hyams et al., 1996); involvement in warfare can have dramatic consequences for the physical and mental health and well-being of military personnel (Pols and Oak, 2007). Few events are more stressful than war, and throughout the history of warfare, it has been repeatedly documented that the trauma of combat, high-stress environments, or simply being deployed to a theater of war can have immediate and long-term disruptive physical, psychologic, and other consequences in those who are deployed to foreign soil and to their family members (IOM, 2008).
Changes in weaponry, strategy, and technology have had well-documented effects on wounding mechanisms and patterns, injuries, and casualty rates (e.g., Owens et al., 2008). However, clusters of physical symptoms and the symptom patterns observed have not changed dramatically (Marlowe, 2001) or at least are not readily distinguishable among various wars (Jones et al., 2002). One can make a reasonable case that the psychologic wounds of war also are not dramatically new or different (Tanielian and Jaycox, 2008):
Combat stress (historically termed soldier’s heart, shell shock or battle fatigue) is a known and accepted consequence of warfare. Although diagnoses such as PTSD [posttraumatic stress disorder] were not formally defined and adopted until the 1970’s [formalized by inclusion in the third edition of the Diagnostic and Statistical Manual of Mental Disorders in 1980], the existence of psychiatric casualties in war undoubtedly goes back as far as warfare itself. (Marlowe, 2001; Rosenheck and Fontana, 1999)
This chapter provides a historical perspective of physical, mental, physical, and other outcomes from previous conflicts and what we might learn about readjustment needs related to them, but its primary focus is on mental health outcomes; physical injuries will be discussed in Chapter 4. A number of textbooks in military medicine offer a more complete historical perspective and review more fully the array of medical challenges and outcomes faced by military personnel during mobilization and deployment and after deployment, including two volumes in the Borden Institute’s Textbooks of Military Medicine series: Military Preventive
Medicine: Mobilization and Deployment, Vol. 1 (2003); and Military Preventive Medicine: Mobilization and Deployment, Vol. 2 (2005). This chapter also discusses the differences between the previous conflicts and the current wars in Iraq and Afghanistan.
FROM ANCIENT GREECE AND ROME TO THE RUSSO-JAPANESE WAR
In effect, PTSD has existed for centuries, although it has been given various names (Bille, 1993; Thakur, 2008). Early Greek, Roman, and Egyptian descriptions of the effects of war refer to acute stress reactions (Kennedy and Duff, 2001). Gabriel (1987), for example, cited many references to psychologic casualties in the Greek and Roman armies, noting that combat-related mental health problems are well known throughout history. In ancient Rome, legionnaires were encouraged to settle in rural areas after their wars, to “decompress” gradually in the serenity of isolation from the city's activity. Japanese lore tells of samurai warriors who retired to tend the “perfect garden,” away from other people and the stresses of warfare (Williams, 1987). Nostalgia was a term coined in the late 17th century to describe young soldiers returning from war who “cease[d] to pay attention and [became] indifferent to everything which maintenance of life requires of them” (Auenbrugger and Neuberger, 1966). During the Napoleonic wars, physicians recognized multiple factors related to nostalgia—including cultural, social, and environmental issues—in addition to participation in battle itself (Thakur, 2008).
Prevention of and treatment for nostalgia were important interests during the Civil War (Hammond, 1883), generally viewed as the first modern war. Nostalgia was seen as including a cluster of stress-induced symptoms known as soldier’s heart, irritable heart, and effort syndrome—symptom patterns classified in more recent times under the various rubrics of combat fatigue, battle shock, combat stress reaction, and PTSD (IOM, 2008; Marlowe, 2001). During the Russo-Japanese War (1904–1905), the first detailed description of “war neurosis” emerged with the first use of psychiatric specialists by the Russians (Thakur, 2008).
Not surprisingly, the evolving perceptions of warfare and its aftermath over many centuries are reflected in the folklore and literature of various cultures and societies. For example, Boman (1987) provides a broad historical perspective documenting that the stereotyped representation of the dangerous and unpredictable ex-serviceman—as reflected in adverse publicity about the propensity of veterans of the Vietnam conflict to indulge in violent, antisocial, and criminal behaviors—is by no means a modern phenomenon. Sir James Frazer in The Golden Bough (1978) and Sigmund Freud in Totem and Taboo (1960) both noted how returning warriors in primitive societies were regarded as dangerous and tainted and often requiring a period of ritual isolation and cleansing before being accepted back into the community. Western civilization since Homeric times has displayed a morbid fascination with the violent (and quite often gruesome) deeds of veterans of the Trojan wars, as amply documented in the Iliad and the Odyssey and retold for Roman audiences in the Aeneid. Several Shakespearean plays refer to acute stress reactions and include particularly adverse characterizations of a “nefarious collection of war veterans,” including Sir John Falstaff, Richard III, Iago, Macbeth, and Cassius.
WORLD WAR I, WORLD WAR II, AND THE KOREAN CONFLICT
Although contemporary accounts indicate that stress-induced disorders existed in previous wars, even in the period of the American Civil War, medical and cultural biases were such that no taxonomy for recognizing and diagnosing them was readily available (Marlowe, 2001). It was not until World War I that specific clinical syndromes came to be associated with combat duty; previously, such casualties were assumed to reflect poor discipline or cowardice (Goodwin, 1987). The thinking that dominated diagnostic thought and ways of treating stress-related illnesses in World War I and World War II (and beyond) developed in the late 19th and early 20th centuries and included new categories of diagnoses related to hysteria, hypochondria, and neurasthenia (Marlowe, 2001). The guiding conceptual and theoretical developments emerged from advances in psychiatry and in turn influenced the evolution of the field in civilian society (Pols and Oak, 2007):
The involvement of psychiatrists in military conflicts [during the 20th century] not only resulted in the development of extensive expertise in the management of war-related psychiatric syndromes but also profoundly affected the development of the entire discipline of psychiatry, which incorporated new theoretical perspectives, diagnostic categories, and treatment strategies first proposed and developed by military psychiatrists.
First observed during the Russo-Japanese War (Marlowe, 2001), shell shock—the signature injury of World War I (Jones et al., 2007)—and war neurosis became the popular labels given to acute physical and psychologic symptoms and reactions to combat (Rundell et al., 1989). Shell shock was initially thought to result from brain concussion from nearby shell explosions (for example, from artillery), but the recognition that the symptoms characteristic of shell shock and effort syndrome could also emerge without exposure to explosions suggested psychologic origins (Hyams et al., 1996; Jones et al., 2007; Shephard, 2001; Thakur, 2008). Symptoms of classic war neurosis first described clearly during World War I were similar to those later described by veterans of the Vietnam conflict (Goodwin, 1987). The prolonged chronic symptoms observed in the Vietnam War were later recognized and labeled “postcombat psychiatric disorder” (Sargent and Slater, 1940). Of the 2 million men sent overseas during World War I, about 8% (153,994) were lost to the war effort because of psychologic problems (Strecker, 1944).
The most comprehensive recent review of research evidence on the physiologic, psychologic, and psychosocial effects of deployment and deployment-related stress on health and well-being (IOM, 2008) explicitly included epidemiologic studies of veterans of World War II, the Korean War, and more recent conflicts. The research evidence base on those cohorts is much narrower than that on cohorts of the Vietnam War and more recent conflicts, but evidence of persistent effects, especially with regard to psychologic consequences and PTSD, was observed in those who served in the earlier wars.
During World War II, the psychologic symptoms ascribed to war neurosis were called battle or combat fatigue or exhaustion (Marlowe, 2001; Thakur, 2008). During the early years of that war, psychiatric casualties had increased by some 300% over those in World War I even though the preinduction psychiatric-rejection rate was “three to four times higher” (Figley, 1978). Overall, 1.39 million men suffered some psychiatric symptoms, and 38% (504,000) of
those who saw combat were permanently lost to the war effort (Ginzberg et al., 1955). Many of the psychiatric casualties were returned to combat after treatment near the front line (Grob, 1994; Shephard, 2001), and a persistent and chronic form of battle fatigue was observed in many veterans who were hospitalized for neuropsychiatric care (Friedman et al., 1994; Grob, 1994; IOM, 2008; Southwick et al., 1994). Grinker and Spiegel (1945), for example, described such cases of “war neurosis” in members of combat air crews, and several studies followed World War II veterans after their combat experiences 5 years (Brill and Beebe, 1955), 10 years (Futterman and Pumpian-Midlin, 1951), 15 years (Archibald et al., 1962), 20 years (Archibald and Tuddenham, 1965), and 24 years (Keehn et al., 1974).
It was during World War II that the major paradigm for viewing the psychologic and psychosocial consequences of deployment shifted “from causation based upon constitutional predisposition in markedly vulnerable population subsets to the concept that all normal human beings could break down. Any soldier could be made behaviorally dysfunctional as well as physically symptomatic by the stresses, anxieties, and strains affecting him in the war zone environment” (Marlowe, 2001).
Those concepts were carried forward to the Korean War, but they and the operational structures and practices used for handling and treating such combat-related stress were initially forgotten. In the first year of the Korean War, men were lost to psychologic symptoms at a rate of 250 per 1,000—almost 7 times the rate in World War II (Blair and Hildreth, 1991). As the war became more stabilized, the rate fell to an average of 32 per 1,000 men, slightly lower than the rate in World War II (Gabriel, 1987).
Comparative studies of health status among war cohorts have found that combat exposure and violence are generally associated with psychiatric disorders in World War II, Korean Conflict, and Vietnam-era veterans (Archibald and Tuddenham, 1965; Breslau and Davis, 1987; Elder and Clipp, 1989; Fontana and Rosenheck, 1994a; National Center for Posttraumatic Stress Disorder, 2008). However, many of the studies grouped World War II and Korean veterans together rather than treating them as distinct cohorts for separate analyses, thereby potentially confounding differences in health effects that reflect widely varied circumstances of service in the two wars (Fontana and Rosenheck, 1994a; Villa et al., 2002).
THE VIETNAM WAR
The war in Vietnam, in which more than 3 million American military service members participated in 1964–1975 and more than 58,000 died, was the longest military conflict in US history. It also heralded critical shifts in how wars are fought (for example, the “war without fronts”) and in how the effects of war-zone deployment on the physical and mental health of US service members were studied.
As noted above, studies of prior wars were limited by reliance on samples of convenience and failure to include adequate measures of important war-zone stressors and other exposures that have potential long-term consequences for the postwar health and well-being of those who served. We summarize here key findings of studies of the Vietnam War with respect to war-zone stressor exposure, prevalence of psychosocial and health-related readjustment problems, and risk factors for development of readjustment problems. The purpose is to provide some context for
the readjustment problems that could be associated with psychosocial and health-related outcomes common in the current conflicts.
Assessment of Exposure to Combat and Other War-Zone Stressors
One of the first studies of a community sample (that is, not a treatment-seeking sample) of war-zone–deployed military service members to attempt to assess specific details of war-zone stress exposure, conducted by the Center for Policy Research, led to the publication of Legacies of Vietnam: Comparative Adjustment of Veterans and Their Peers (Egendorf et al., 1981). The legacies investigators developed de novo a 10-item, self-report scale of events that are indicative of combat exposure, for example, firing on the enemy, receiving fire, and encountering mines or booby traps. On the basis of responses about the 10 items, the investigators classified 27% of participants as having experienced heavy combat exposure, 31% medium exposure, 33% low exposure, and 9% no exposure.
Similarly, the Vietnam Experience Study (VES), conducted by the Centers for Disease Control (CDC, now the Centers for Disease Control and Prevention) in the mid-1980s (CDC, 1988a, 1988b), was part of a three-component effort to assess the health effects of service in Vietnam, including morbidity and mortality. Findings based on the proxy measures controlling for combat exposure indicated that 72% of Vietnam-veteran participants began their military service before 1969, 34% had a tactical primary Military Occupational Specialty, and 57% served in a combat unit (infantry, artillery, armor, cavalry, or engineer). Secondary analysis of VES data (Barrett et al., 1996) indicated that, according to the modified combat scale, 23% of the VES Vietnam veterans had low or no combat exposure, 22% medium exposure, 29% high exposure, and 26% very high exposure.
In the National Vietnam Veterans Readjustment Study (NVVRS) (Kulka et al., 1990), the investigators used a set of nearly 100 survey interview items—items from prior studies and new items that covered domains not previously included—to assess war-zone stress exposure. NVVRS analyses identified four multi-item stressor-exposure dimensions for men (exposure to combat, exposure to abusive violence and related conflicts, deprivation, and loss of meaning and control) and six for women (exposure to wounded and dead, exposure to enemy fire, direct combat involvement, exposure to abusive violence, deprivation, and loss of meaning and control). For both sexes, secondary factor analyses suggested that a single index captured the variance across the multiple dimensions well, and this supported the use of a single, overall exposure indicator. Additional analyses supported determination of cut points to separate “high” exposure from “low–moderate”; 25% of men and 40% of women were classified as having high exposure to war-zone stress. Although the more detailed measures of exposure to war-zone stressors were developed in the context of studies of the Vietnam War helped us to understand the impact of war on combatants, the fact that most of the studies’ exposure measures relied on retrospective self-reporting has been a cause of concern because it could open the door to bias from exaggeration of exposure (e.g., McNally, 2003, 2005).
To assess the validity of that criticism empirically, Dohrenwend and colleagues (2006, 2007) used military and other archival records to create individualized “military historical measures” (MHMs) of probable exposure of each of the 1,200 male Vietnam veterans who participated in the NVVRS to combat and other war-zone stressors. An MHM is the casualty rate in the unit in which the person served during service in Vietnam. Findings from analyses of the
correspondence of self-reports with archival information include documentation of a strong positive correlation between the Dohrenwend et al. MHMs and the NVVRS self-report measures. Dohrenwend et al. also noted that more than 90% of 10 veterans classified as low probable exposure on the basis of archival information were classified as low–moderate on the basis of NVVRS self-reports and that 72.1% of those classified as very high probable exposure on the basis of archival information were classified as high exposure on the basis of self-reports. The latter finding is consistent with understating, rather than exaggerating, exposure.
Outcomes (Readjustment Problems)
When the Vietnam War ended in 1975, a debate emerged over the nature and extent of the problems that veterans of the conflict were experiencing as they returned to civilian life. Many articles and books were published, and readjustment was a popular topic in the mass media, on television, and in movies. Some saw Vietnam veterans as “walking time bombs,” and others claimed that most returnees had readjusted easily and were leading productive lives.
Empirical studies of Vietnam-veteran readjustment have suggested that, in essence, both claims were true. The NVVRS research team concluded that “the majority of Vietnam theater veterans have made a successful re-entry to civilian life and currently experience few symptoms of PTSD or other readjustment problems” (Kulka et al., 1990), but that for a sizable minority of men and women who served in Vietnam, “the war is not yet over” in that they continued to suffer from emotional turmoil a decade or more after they ended their military service. Findings also demonstrated that those with PTSD were at very high risk for a broad spectrum of other readjustment problems, such as relationship problems, depression, substance abuse, unemployment, and violence.
We summarize below empirical findings about some of the important readjustment problems that have been shown to be associated with service in Vietnam.
PTSD, Depression, and Other Mental Health Problems
After the end of the war, estimates based on expert opinion or clinical observation suggested that as few as 250,000 (Wilson, 1978) or as many as 2 million of the 3 million (Egendorf, 1982) men and women who served in the war had developed PTSD. The introduction of PTSD into the official psychiatric nosology in the United States in 1980, however, stimulated community epidemiologic studies of war-related outcomes in Vietnam veterans, many of which focused on PTSD. The most comprehensive assessment of the prevalence of PTSD and other readjustment problems among Vietnam veterans comes from the NVVRS (Kulka et al., 1990). In 1986–1987, the NVVRS team assessed nationally representative samples of Vietnam-theater veterans (n = 1,632), other veterans of the war era (n = 716), and civilian counterparts (n = 668) matched to the theater veterans on age, sex, and race or ethnicity. Cases of PTSD were identified on the basis of a comprehensive, multimeasure assessment that included self-report scales and semistructured clinical assessments. Findings indicated that 15.2% of male and 8.5% of female Vietnam veterans had current PTSD (preceding 6 months) at the time of the study. In contrast, current PTSD prevalence estimates based on the same comprehensive assessment procedure among other era veterans were 2.5% in men and 1.1% in women and among civilian counterparts were 1.2% in men and 0.3% in women. Estimates of lifetime prevalence in Vietnam veterans, based on semistructured clinical interviews, were 30.9% in men and 26.9% in women.
The other epidemiologic studies of Vietnam veterans focused on smaller subsets of the population, used less comprehensive assessments, or both. Those studies reported somewhat lower lifetime prevalence of PTSD when compared with the results from the NVVRS study. For example, O’Toole et al. (1996) studied physical and mental health outcomes in a simple random sample of male members of the Australian Army who served in Vietnam (n = 641). On the basis of the semistructured clinical interviews conducted in 1990–1993, the current prevalence of PTSD was estimated to be 11.6% and the lifetime prevalence 20.9%. Similarly, in the VES (CDC, 1988c), investigators examined health and mental health outcomes in a cohort of Army enlisted men who served a single a tour of duty in Vietnam and a similar cohort who did not serve in Vietnam. On the basis of survey interviews conducted in 1985–1986, the CDC team estimated a current prevalence of PTSD (in the preceding month) of 2.2% and a lifetime prevalence of 14.7% in Vietnam veterans. CDC investigators did not report PTSD prevalence estimates for the comparison group.
The VA study (Goldberg et al., 1990) included only male, monozygotic twin pairs who served in the US military during the Vietnam era; all participants were drawn from VA’s Vietnam Era Twin Registry. Using information collected by a mixture of mailed questionnaires and telephone interviews conducted in 1987 that included an ad hoc PTSD assessment, the investigators estimated the prevalence of PTSD in the 715 twin pairs who were discordant for Vietnam service (that is, one twin served in Vietnam, and the other served in the military but not in Vietnam) to be 16.8% in twins who served in Vietnam compared with 5.0% in twins who served elsewhere.
Finally, investigators from one of the five sites of NIMH’s Epidemiologic Catchment Area study (Helzer et al., 1987) reported PTSD prevalence based on survey interviews conducted in 1982 with self-identified Vietnam veterans (n = 64) in a community (St. Louis area) sample. Findings suggested a lifetime PTSD prevalence in those who reported being wounded in combat of 20% (three of 15), and a lifetime prevalence in combat veterans who did not report being wounded of 4% (one of 28).
Those and other studies also documented other mental health problems. The NVVRS documented a higher prevalence of current major depression in Vietnam veterans than in era veterans (in males, 2.8% versus 0.5%; in females, 4.3% versus 1.4%). CDC’s VES also documented a higher prevalence of depression in male Vietnam veterans than in era veterans (4.5% versus 2.3%). More important, the NVVRS documented that the prevalence of major depression was closely related to the prevalence of PTSD: the prevalence of current major depression was 15.7% in male Vietnam veterans with current PTSD and 0.5% in those without and 23.0% in female veterans with current PTSD and 2.3% in those without.
NVVRS findings on current substance-use disorders showed a similar pattern of comorbidity with PTSD. The prevalence of current alcohol abuse or dependence was 22.2% in male Vietnam veterans with current PTSD and 9.2% in those without and 10.1% in female veterans with current PTSD and 1.5% in those without. Those findings are consistent with findings from studies of PTSD associated with other categories of traumatic event as well—PTSD is frequently accompanied by both depression and substance abuse.
Concerning comorbidity, both general population studies (Breslau et al., 1991; Helzer et al., 1987; Kessler et al., 2005) and studies of Vietnam veterans (see Deering et al., 1996; Schlenger et al., 1999, for reviews) indicate that the experience of other psychiatric disorders is
common among people with PTSD. High rates of lifetime or current diagnoses of the following disorders have been reported in Vietnam veterans with PTSD: major depression and dysthymia, anxiety disorders other than PTSD, substance-use disorders, and in male veterans, antisocial personality disorder. Some data suggest that the occurrence of substance-use disorders in people with PTSD may result from efforts to reduce the intensity of PTSD symptoms (e.g., Chilcoat and Breslau, 1998).
The most comprehensive assessment of the physical health status of Vietnam veterans was conducted in the VES (CDC, 1988b), in which a subset of Vietnam-veteran participants (n = 2,490) and comparison participants (n = 1,972) in the VES interview component underwent standardized physical examinations conducted at a single clinic in 1987. Interview findings indicated that although 80% or more of both groups rated their health as “excellent” or “good,” more Vietnam veterans than comparisons rated their health as “fair” or “poor” (19.6% versus 11.1%). Medical examination results, however, showed few statistically significant differences between Vietnam veterans and comparisons, particularly given the very large number of comparisons made.
The NVVRS also included a self-report list of chronic conditions, and findings indicated no differences in reports of chronic conditions between male Vietnam veterans and era veterans. Substantial differences were found, however, between Vietnam veterans who reported high versus low–moderate exposure to war-zone stressors. Failure to have taken account of stressor exposure in the analyses is an alternative explanation of why the VES found little concordance between survey report and medical examination findings.
O’Toole et al. (2009) assessed health status and its correlates in a longitudinal cohort of Australian veterans that they assessed 22 years (1990–1993) and again 36 years (2005–2006) after their service in Vietnam. The presence of health conditions was assessed by self-report, and prevalences were compared with estimates from Australia’s National Health Survey (NHS), with adjustment for age and sex. Findings indicated that the prevalences in Vietnam veterans of 47 of the 67 chronic health conditions covered were higher than the expected prevalences based on the Australian National Health Survey and the prevalences of four were lower. Regression analyses showed that service in the military and having combat-related PTSD decades after the war are consistently related with physical illness in later life.
In addition to prevalence of specific health conditions, studies of Vietnam veterans have examined functioning and quality of life. For example, secondary analyses of NVVRS data by Zatzick et al. (1997) examined the relationship of PTSD to six indexes of functioning and quality of life among male Vietnam veterans. Findings indicated that PTSD was significantly associated with poorer outcome in five of the six domains with sociodemographic characteristics controlled and that the association remained with four domains (physical limitations, current unemployment, compromised physical health, and diminished well-being) even when comorbid psychiatric and physical illnesses were also controlled. Similar secondary analyses that examined those relationships in female Vietnam veterans (Zatzick et al., 1997) found significant associations of current PTSD with five of the six domains with sociodemographic characteristics controlled and that the association remained with three domains (compromised physical health, bed days in preceding 2 weeks, and current unemployment) when comorbid psychiatric and physical illnesses were also controlled.
An alternative approach to examination of health effects of specific exposures is to compare causes of death between those exposed and comparable people who were not exposed. Two large studies of postwar mortality in Vietnam veterans have been conducted: one by VA and one by CDC.
CDC (1987) used military records to select two samples of men who entered service in the Army in 1965–1971, served only one term of enlistment, and achieved a pay grade no higher than E5 at the time of discharge. For the veteran cohort (n = 9,324), only one tour in Vietnam was allowed; comparisons (n = 8,989) were limited to duty in the United States, Germany, or Korea. The initial followup period was from date of discharge (alive) to December 31, 1983. Deaths were identified from multiple sources, including the National Death Index, VA’s Beneficiary Identification and Records Locator Subsystem (BIRLS), the Social Security Administration, and the Internal Revenue Service. Findings indicated that excess all-cause mortality in Vietnam veterans over comparisons occurred primarily in the first 5 years after separation, and that excess was due to external causes of deaths, such as motor vehicle accidents, suicide, homicide, and accidental poisonings. The latter category includes deaths due to overdose of prescription drugs, illicit drugs, or alcohol or any combination thereof. After the first 5 years, mortality in the cohorts was similar “except for drug-related deaths, which continued to be elevated” in the Vietnam veterans. CDC followed the cohorts again (Boehmer et al., 2004), extending the followup period by 17 years (through December 31, 2000). Findings suggested that over the full followup period, the only difference in mortality between Vietnam veterans and comparisons was in external causes of death: Vietnam veterans experienced significantly more deaths from unintentional poisonings, including drugs.
VA’s study of Vietnam-veteran mortality examined veterans who died after leaving the service. Using VA’s BIRLS file, VA investigators (Breslin et al., 1988) identified 24,235 men who served in the US Army or Marine Corps in Vietnam and died 1965–1982, and 26,685 Army or Marine Corps veterans who had not served in Vietnam but had died in the same period. Findings indicated significant excess deaths in the Vietnam veterans due to motor-vehicle accidents, non–motor-vehicle accidents, and accidental poisonings. In addition, Marine Corps veterans, but not Army veterans, appeared to have excess deaths due to lung cancer and non-Hodgkin lymphoma. VA investigators (Watanabe et al., 1991) later added 11,325 Army or Marine Corps veterans who died in 1983–1984 to the cohort studied earlier. The enhanced study included two additional referent groups to strengthen the ability to draw causal inferences. Findings indicated that Army veterans experienced excess deaths due to external causes, laryngeal cancer, and lung cancer, and Marine Corps veterans experienced excess deaths due to external causes. With the larger sample, it was possible to attribute the earlier finding of excess Marine Corps deaths to a lower-than-expected number of deaths in marines who had not served in Vietnam rather than to an excess in those who had.
Other Psychosocial Problems
A variety of readjustment problems in addition to mental and physical health problems have been studied. We summarize here some of the key findings.
In the NVVRS, all subgroups of male Vietnam veterans reported significantly more violent acts in the preceding year than the comparison groups and scored higher on a scale of
active expression of hostility. Vietnam veterans with high exposure to war-zone stressors reported the highest rates of violence and hostility. Male Vietnam veterans with PTSD were nearly 6 times as likely to report a history of homelessness or vagrancy as those without. Overall, 35% of male veterans with PTSD reported a history of homelessness or vagrancy, 40% scored at the highest level of hostility, 25% reported committing 13 or more acts of violence in the preceding year, and almost 50% reported having been arrested or jailed more than once since the age of 18 years. Female Vietnam veterans, including those with high exposure to war-zone stressors, reported fewer violent acts in the preceding year than the comparison groups.
Similarly, Vietnam veterans with PTSD reported substantially more family and relationship problems than those without. The NVVRS included interviews with the spouses or partners of a subsample of Vietnam veterans. Jordan et al. (1992) noted that separate interviews with Vietnam veterans and their spouses or partners document that there are many serious problems in the families of those with PTSD. Findings indicated higher levels of violence, higher levels of psychologic distress in spouses and partners, and the greater likelihood that children in these families will have behavioral problems than the children of veterans without PTSD.
Finally, a review of the little empirical research on associations between traumatic-stressor exposure and labor-market outcomes for Vietnam veterans conducted 25 years after the end of hostilities in Vietnam suggested that exposure to war-zone stressors not only compromises mental and physical health but can have deleterious economic consequences (Fairbank et al., 1999a). For example, among employed male Vietnam veterans in the NVVRS, those who met criteria for current PTSD earned significantly less per hour than those without PTSD. White and Hispanic Vietnam veterans who currently met criteria for war-related PTSD were also less likely to be employed more than a decade after the war ended than were their counterparts without PTSD. In black veterans, higher levels of exposure to war-zone stressors were associated with a greater likelihood of not being employed, although the association between war-related PTSD and employment status was not statistically significant (Fairbank et al., 1999b).
Risk Factors for Readjustment Problems
Because exposure to trauma is always included in observational studies (we do not randomize people to different magnitudes of trauma exposure), the scientific basis for attributing PTSD symptoms to combat or other exposures must rely on quasiexperimental designs. To examine the potential predisposition or other factors that contribute to the development of combat-related PTSD, the NVVRS team (Kulka et al., 1990) did extensive modeling of the correlates of PTSD prevalence among the multiple quasiexperimental comparison groups included in the design, such as high versus low–moderate war-zone stressor-exposure groups of theater veterans, theater veterans versus era veterans.
The modeling found that the differences between groups in PTSD prevalence observed in the NVVRS cannot be explained fully by differences in premilitary characteristics or exposures, although there are important premilitary risk factors for combat-related PTSD. Clearly, the most influential risk factor is the degree of exposure to combat and other war-zone stressors. Specific other factors that played important roles included lower age at the time of exposure; problem behaviors in childhood, particularly the symptoms of antisocial personality disorder; growing up
in a family that had trouble making ends meet; and having one or more first-degree relatives who had a mental disorder.
Fontana and Rosenheck (1994a) used structural equation-modeling techniques to examine causality in secondary analyses of the NVVRS data. They found that in addition to exposure to war-zone stressors, factors contributing to combat-related PTSD included lack of support from family and friends on homecoming, Hispanic ethnicity, having been abused as a child, and family instability.
More broadly, research involving Vietnam veterans indicates that in addition to the nature and severity of the specific stressor exposure, both pre-exposure and postexposure factors can affect the probability of PTSD after exposure. In the general population, the most consistently reported pre-exposure risk factors for PTSD in people exposed to trauma are female sex, pre-existing psychiatric disorder, family history of psychopathologic conditions, minority-group status, lower age at the time of the exposure, and prior exposure to trauma, including abuse in childhood (Breslau et al., 1991, 1998; Brewin et al., 2000; Bromet et al., 1998). Like general-population studies, analyses of NVVRS data have found associations between combat-related PTSD in Vietnam veterans and instability in the family of origin, antisocial behavior in childhood, being Hispanic, being younger at the time of exposure, and prior history of trauma (Fontana, 1997; Fontana and Rosenheck, 1994b; King et al., 1999; Schlenger et al., 1999).
Compared with research on pre-exposure factors, however, relatively few studies have examined the role of postexposure factors in PTSD. In the NVVRS, stressful life events and a lack of social support in the postwar period were found to place Vietnam veterans at increased risk for PTSD (Fontana and Rosenheck, 1994b; Fontana, 1997; King et al., 1999). Although NVVRS findings have provided some insights into the role of prewar and postwar experiences in PTSD in Vietnam veterans, the insights are somewhat limited by the NVVRS’s less comprehensive assessment of civilian stressors.
THE PERSIAN GULF WAR
By historical standards, the 1991 Persian Gulf War (Operation Desert Storm) was unusual in many respects (cf. Marlowe ):
It was mostly an air war against an overmatched enemy.
It was short.
It resulted in very few casualties for the coalition (fewer than 200 were killed).
Yet the most striking aspects of that deployment occurred after the Gulf War was over, when thousands of veterans began reporting a wide variety of symptoms—sleeplessness, aching joints, memory loss—that remained undiagnosed, many evocative of those reported by veterans of previous wars and attributed to the psychologic trauma of combat (Marlowe, 2001).
In response to growing concerns about the physical and psychologic health of Gulf War veterans of the 1990–1991 conflict, Congress passed two laws in 1998, PL 105-277 and PL 105-368, directing the secretary of veterans affairs, through the National Academy of Sciences, to review and evaluate the scientific and medical literature regarding associations between illness and exposure to toxic agents, environmental or wartime hazards, and preventive medicines or vaccines in members of the armed forces who were exposed to such agents and to identify “other
agents, hazards, or medicines or vaccines to which members of the Armed Forces might have been exposed.” Five years after the official end of the 1991 Gulf War, the Presidential Advisory Committee on Gulf War Veterans’ Illnesses concluded that psychologic stress was probably a major contributing factor to the broad array of illnesses in Gulf War veterans (Lashof et al., 1997) and encouraged the government to continue research on stress-related disorders.
In response to those laws, the Institute of Medicine (IOM) has carried out a comprehensive, continuing program to examine health risks posed by specific agents and hazards to which Gulf War veterans might have been exposed during their deployment has resulted in several major reports, including one on the impact of deployment itself (IOM, 1995, 1996, 1999, 2000, 2003, 2004, 2005, 2006a,b). Gulf War and Health, Volume 4: Health Effects of Serving in the Gulf War (2006a) found that veterans of the Gulf War report higher rates of nearly all the symptoms examined than their nondeployed counterparts, including not only individual symptoms but also chronic multisymptom illnesses and such conditions as fibromyalgia, chronic fatigue syndrome, and multiple chemical sensitivity. The literature reviewed also indicated that deployment places the veterans at increased risk for a number of psychiatric illnesses, including PTSD, other anxiety disorders, depressive disorders, and substance abuse.
Those results and growing concerns regarding the nature of OEF and OIF and the deployment of the veterans resulted in a more comprehensive review and evaluation of physiologic, psychologic, and psychosocial effects of deployment-related stress on military veterans from World War II through the conflicts in Afghanistan and Iraq, which placed the associations observed in 1991 Persian Gulf War veterans in this broader context (IOM, 2008). The physical and mental health of Persian Gulf War veterans continues to be the subject of active research and debate (e.g., Blanchard et al., 2006; Eisen et al., 2005; Hotopf et al., 2003; Kang et al., 2003), and it is by no means certain that the psychiatric burden of the Persian Gulf War is fully understood (Larson et al., 2008; Pols and Oak, 2007).
In this chapter, we have provided a brief historical perspective or context for describing, viewing, and understanding the potential readjustment challenges and needs of military personnel, veterans, and their families resulting from deployment to the conflicts in Iraq and Afghanistan. It is certainly true that every war is unique in several important respects, but overwhelming empirical evidence on multiple wars clearly documents that exposure to combat, other war-zone stressors, or even deployment itself can have immediate and long-term physical, psychologic, and other consequences and that such consequences have, in most respects, been universal and similar throughout the history of warfare even though the context and nature of warfare have changed dramatically. However, throughout history, society and culture—and the medical and cultural perspectives of the time—have played a powerful role in how the effects of war on soldiers have been viewed, the perceived nature and causes of the effects, and how they were treated. And those factors have changed dramatically. Although such consequences have been observed, documented, and reflected on throughout the history of warfare—and in many societies, cultures, and military organizations—contemporary cultural and medical viewpoints have not provided a viable context, taxonomy, or paradigm for recognizing and understanding their etiology. The cultural, conceptual, and theoretical perspectives on war-zone stress exposure and its consequences continue to evolve. For example, from their comparative study of
symptoms reported by veterans from 1900 to the Persian Gulf War, Jones et al. (2002) noted that the explanations given to war-related syndromes reflect broader conceptual concerns and the state of medical knowledge and of how physicians classify and interpret functional somatic presentations. It was not until World War I that specific clinical syndromes came to be associated with combat duty; previously, such casualties were assumed to reflect poor discipline or cowardice. However, before the Vietnam War, psychiatric consensus held that soldiers who recovered from an episode of mental breakdown during combat would suffer no adverse long-term consequences, and psychiatric disability commencing after the war was believed to result from pre-existing conditions (Pols and Oak, 2007). As a result, military psychiatrists paid little attention to postwar syndromes until after Vietnam, when a major change in psychiatric interest reflected recognition that many veterans suffered from chronic psychiatric disorders, which led, in part, to establishment of PTSD as a distinct diagnostic category in the third edition of the Diagnostic and Statistical Manual of Mental Disorders.
It is also important to note the evolution of military psychiatry throughout the 20th century in its efforts to understand, prevent, and treat for the psychiatric consequences of war. That evolution has encompassed implementation of screening programs to detect factors that predispose people to mental disorders, provision of early intervention strategies for acute war-related syndromes near the front lines (“forward psychiatry”), and mitigation of the symptoms of long-term psychiatric disability after deployment. It has also had substantial effects on the discipline as a whole and has led to the incorporation of new theoretical perspectives, diagnostic categories, and treatment strategies based on the military experiences (Pols and Oak, 2007).
It is in that context that the implications of the current conflicts are best articulated and understood not only for the military leadership but for those who serve in the conflicts and for their families. Although the experiences of those deployed to Iraq or Afghanistan are similar in many respects to the experiences of those deployed in previous conflicts, there are a number of distinctive and important differences in who is serving, how they are deployed, and how the conflicts are being fought. The differences might have substantial consequences for the types and severity of challenges and readjustment issues and problems likely to be experienced by the men and women serving in OEF and OIF and what types of support they and their families need, both within theater and on their return. Moreover, most of the differences are especially notable in that neither our military forces nor the country as a whole has had substantial relevant experience with many of the key features of organization and warfare that make these conflicts most distinctive.
Perhaps the most fundamental difference from past conflicts is that OEF and OIF together make up the longest sustained US military operation since the Vietnam War and the first such extended conflict dependent on a smaller military that comprises only volunteers. Whether or not one agrees that the extended nature of these conflicts has subjected the military to demands that “it was not sized, resourced, or configured to meet” (Tanielian and Jaycox, 2008), that this situation has created a sizable and unique burden on the military and its service members is undeniable, and its potential implications and consequences are legion.
First, the size of the available pool of active-duty personnel and the extended nature of the conflicts have required an unprecedented use of the reserves and National Guard, activated to serve far longer deployments than most had ever expected, experienced, or, arguably, been optimally trained for. The troops also tend to be older, to leave civilian jobs behind, and to return to communities that usually do not have the types of medical, psychiatric, and other support
personnel available to them that were available when they were on active duty. Those characteristics have important implications for successful reintegration and readjustment.
Second—and this also reflects substantial reductions in the number of troops available and the extended nature of the conflicts—the number, length, and pace of military deployments have increased dramatically in recent years, and breaks between deployments have been infrequent. Greatly facilitated by use of the draft, the 12- to 13-month rotational policy established in Vietnam was adopted in part in response to research conducted in World War II (in which military personnel served for the duration of the conflict) because it demonstrated an important relationship between length of time in combat and risk of psychologic breakdown. Cognizant of that history, DOD has established clear rotational policies on length of deployments and length of time between deployments. However, the demands of the current conflicts have made compliance with the policies difficult, and the implications of being unable to meet the standards are of obvious significance for understanding the readjustment needs of service members and their families.
Third, and perhaps more subtle, the standards for a military that is dependent on conscription are different from those for an all-volunteer force. Establishing and maintaining an all-volunteer force place a premium on careful recruitment, screening, selection, and retention; those chosen are in effect special and valuable assets. However, the quality and readiness of those available can vary widely from year to year on the basis of the state of the economy, employment, and other factors and thus require a critical balance between achieving the numbers of men and women required to maintain force levels and screening out those with characteristics that might predispose them to adverse consequences (such as behavior problems and PTSD) but who otherwise are well suited and qualified for the military. Such choices have implications not only for finding enough people to serve but for the potential types of problems experienced when they are deployed and the numbers and types of support personnel (such as psychiatrists and psychologists) required to address the problems both in the theater of operations and when they return.
Fourth, a cluster of distinctive features of obvious significance for readjustment is the nature of the conflicts themselves, including especially the types of warfare experienced and the types of injuries sustained. Military personnel in Afghanistan and Iraq have been exposed to most of the circumstances and experiences of traditional combat seen in previous wars, but a signature and growing feature of the Iraq war in particular (and steadily growing in Afghanistan) is exposure to the tactics of insurgency warfare and guerilla attacks—including suicide and car bombs, IEDs, sniper fire, and rocket-propelled grenades—some of which are reminiscent of the Vietnam War. In effect, beginning with the Vietnam War, US combat engagements have increasingly evolved from engagements of “planned” violence to engagements involving more “random” and unpredictable violence, which poses continuous and unexpected threats to one’s life and the terror, helplessness, and fatalism that accompany such threats and experiences. In OEF and OIF, such warfare is increasingly sophisticated and effective, with explosive mechanisms accounting for over three-fourths of the injuries observed in Iraq and Afghanistan. Survivability rates are much higher than in previous wars, but IED blasts alone often cause multiple wounds, usually with severe injuries to extremities, and traumatic brain and other blast injuries, and they leave many (most of whom would not have survived in previous wars) with serious physical, psychologic, and cognitive injuries. In conjunction with multiple and longer deployments, those factors may pose unique and sobering threats to many who serve; the relative
randomness and unexpected nature of exposure to harm (both of oneself and of others) might put one at substantially greater risk of physical, psychologic, and other effects than those in other conflicts. In turn, the numbers and types of personnel—such as physicians, psychiatrists, psychologists, and other specialists—that are required to support and treat those who serve before, during, and after deployment—will probably be substantial.
Although the last three decades have seen much improvement in the empirical documentation of postwar outcomes in military service members (and to a smaller extent in their families), there is still much work to be done. For example, Tanielian and Jaycox (2008) reviewed 22 epidemiologic studies of returnees from deployment to OEF and OIF and found that only one included clinical diagnostic assessment for PTSD and other psychiatric disorders. The other 21 studies identified “cases” solely on the basis of brief, self-report screening scales or from medical records. Although screening scales and medical records are useful for many purposes, Tanielian and Jaycox note that using either as the sole basis of estimating the prevalence of PTSD and other psychiatric disorders is fraught with challenges—a finding echoed by an earlier IOM report (2006b). More broadly, although the reported studies have built on the experiences from prior conflicts and made valuable contributions to our knowledge about mental health and other outcomes associated with deployment to a war zone, they have a set of common limitations, including
Reliance on samples of convenience, which limits their external validity (generalizability).
Reliance on brief screening instruments to identify cases of key outcomes and for prevalence estimates, which limits their internal validity.
Use of cross-sectional designs, which limits their ability to support causal inference and to elucidate the course of a disorder.
Assessment of narrow sets of risk and protective factors, which results in underspecified models with a high risk of bias.
In addition, many of the studies have been conducted by VA or DOD rather than by independent third parties, and this raises important questions about the validity of self-reports, particularly with regard to sensitive issues.
All those limitations are understandable, given the fiscal and practical challenges involved in conducting long-term outcome studies (for example, longitudinal epidemiologic studies are expensive and difficult to implement). The point, however, is that to be useful in the formulation of policy, studies need to be both scientifically sound and comprehensive.
The committee recommends that the Department of Defense, the Department of Veterans Affairs, and other federal agencies fund research on readjustment needs of returning OEF and OIF veterans, their families, and their communities that explicitly addresses methodologic and substantive gaps in completed and ongoing research. For example, the support of large-scale, independent studies with longitudinal designs, probability sampling, comprehensive clinical assessment of key outcomes, and more fully specified models that include objective biologic measures should be considered.
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