reviewed by the committee, however, did not demonstrate the array of effects seen in the experimental literature.

The epidemiologic literature on deployed vs nondeployed veterans yielded sufficient evidence of an association between deployment to a war zone and psychiatric disorders, including posttraumatic stress disorder (PTSD), other anxiety disorders, and depression; alcohol abuse; accidental death and suicide in the first few years after return from deployment; and marital and family conflict, including interpersonal violence. For several health and psychosocial effects—such as unexplained illness, drug abuse, chronic fatigue syndrome, gastrointestinal symptoms consistent with functional gastrointestinal disorders, skin diseases, incarceration, and fibromyalgia and chronic widespread pain—there was limited and suggestive evidence of an association. For the majority of health effects, the epidemiologic data were insufficient or too inconsistent to determine whether an association existed. The committee also found that deployed veterans report more symptoms and medical conditions and poorer health than veterans who were not deployed, particularly those deployed veterans with PTSD. The prevalence and severity of PTSD was associated with increased exposure to combat.

The conclusions reached by the committee regarding various health and psychosocial effects are presented in Table 8-1.

TABLE 8-1 Summary of Findings Regarding the Association Between Deployment to a War Zone and Specific Health and Psychosocial Effects

Sufficient Evidence of a Causal Association

Evidence from available studies is sufficient to conclude that there is a causal relationship between deployment to a war zone and a specific health outcome in humans. The evidence is supported by experimental data and fulfills the guidelines for sufficient evidence of an association (below). The evidence must be biologically plausible and satisfy several of the guidelines used to assess causality, such as strength of association, dose-response relationship, consistency of association, and temporal relationship.

  • No effects.

Sufficient Evidence of an Association

Evidence from available studies is sufficient to conclude that there is a positive association. That is, a consistent positive association has been observed between deployment to a war zone and a specific health outcome in human studies in which chance and bias, including confounding, could be ruled out with reasonable confidence. For example, several high-quality studies report consistent positive associations, and the studies are sufficiently free of bias and include adequate control for confounding.

  • Psychiatric disorders, including PTSD, other anxiety disorders, and depressive disorders.

  • Alcohol abuse.

  • Accidental death in the early years after deployment.

  • Suicide in the early years after deployment.

  • Marital and family conflict.



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