Numerous investigators have suggested that psychiatric disorders may occur as a consequence of serving in the military during wartime. There are reports associating war-zone trauma with mental illnesses as far back as the Civil War (Pizarro et al. 2006; Wessely 2005), even though the terminology used to classify war-related psychiatric traumatic events has changed considerably. Despite these changes in terminology, there is a substantial literature on the psychiatric effects of war in general, mainly in the context of trauma. There are reports on the prevalence of a wide array of psychiatric disorders and their association with being a veteran (for example, Beebe 1975; Robins et al. 1974; Snow et al. 1988) and with specific combat experiences, including witnessing death and atrocities (Archibald and Tuddenham 1965; Grinker and Spiegel 1945; Kardiner and Spiegel 1947). This section focuses on assessing the evidence of a relationship between deployment-related stress and psychiatric disorders. Substance-use disorders are discussed in the next section.
The challenge for the committee in understanding the plethora of studies available on several potentially diverse cohorts of veterans was first to distinguish clearly between the primary and secondary studies and then to identify studies that explicitly used deployment to a war zone as the exposure of interest in contrast with studies that used serving in the military during wartime, but not necessarily deployment to a war zone, as an overall indicator of risk of development of any psychiatric disorder. As described in Chapter 1, the committee agreed that studies that used PTSD as a presumed marker for deployment-related trauma would also be included in this analysis.
Primary studies provided the basis of the committee’s findings on the relationship between deployment-related stress and psychiatric effects. Primary studies were those in which exposure status was determined according to whether subjects had been deployed, not deployed, or deployed to a nonwar zone (for example, Germany) or that used a diagnosis of PTSD as a marker of war-zone trauma. To diagnosis psychiatric disorders and PTSD, primary studies also included an in-person interview and used either the Structured Clinical Interview for DSM-III-R (SCID); the Composite International Diagnostic Interview (CIDI), a comprehensive and standardized diagnostic interview designed for assessing mental disorders according to the definitions of the Diagnostic Criteria for Research of ICD-10 and DSM-III-R; or the DIS, a research diagnostic interview that assesses psychiatric disorders according to DSM-III-R criteria but is designed to be administered by trained lay interviewers; or the CAPS. Primary studies are summarized in Table 6-3.
The secondary studies reviewed and evaluated the same functional domains of interest—such as depression, anxiety, and substance use—and add supplementary information that may increase or decrease confidence in the conclusions drawn from the primary studies.
The committee identified 11 citations for 7 primary studies (CDC 1988a; Dohrenwend et al. 2006; Fiedler et al. 2006; Ikin et al. 2004; Jordan et al. 1991; Koenen et al. 2003a,b; Kulka et al. 1990; Proctor et al. 2001; Toomey et al. 2007; Wolfe et al. 1999).
The VES was a major study of U.S. Army Vietnam veterans that began with a postservice mortality study (CDC 1987). CDC (1988a) used the cohort to identify and recruit a