were 80.5% and 56.8%, respectively (Kelsall et al. 2004a). In the Australian contingent sent to the Gulf War, members of the Navy were heavily overrepresented (86.5%). Very few experienced direct combat. Despite their lack of combat exposure, deployment was a stressful event: deployed veterans experienced higher rates of fear and threat of entrapment, attack (including nerve-agent warfare), and death or injury (Ikin et al. 2004). Participants completed a mailed questionnaire, which consisted of a physical and mental health screening questionnaire (SF-12), a test for nonpsychotic psychologic illness (GHQ-12), a PTSD checklist (PCL-S), and a questionnaire about military service and exposures. Thirty-one percent of Gulf War veterans had developed DSM-IV diagnoses since the Gulf War compared with 21% of non-Gulf War veterans. Significant excesses were seen in PTSD, depression, and substance-use disorders. A more recent study of Australian Navy Gulf War veterans noted that those veterans reported many stressful experiences, including fear of death and perceived threat of attack, more frequently in relation to the Gulf War than other military services (Ikin et al. 2005). The study population was the entire cohort of 1,579 veterans deployed to the 1991 Gulf War, but in the final analysis, results were restricted to 1,232 male participants.
Kelsall et al. (2004a) stated that participants in the exposed cohort reported a higher prevalence of all symptoms and reported more severe symptoms. McKenzie et al. (2004) reported that Gulf War veterans had poorer psychologic health and that the number of stressful exposures correlated with poorer scores on three standard instruments used to measure functioning and psychologic health.
Forbes et al. (2004) used factor analysis to attempt to group symptom complexes for this cohort. Three factors emerged as more prominent in Gulf War veterans—psychophysiologic distress, somatic distress, and arthroneuromuscular distress and the symptoms in those complexes were more severe in Gulf War than in non-Gulf War veterans. This well-designed study confirms the extent and greater severity of symptoms in Gulf War veterans, even in a predominantly naval population with few direct military attacks, no deaths, and few casualties. The results suggest a deployment effect in the absence of actual combat.
Greater symptom severity was associated with 10 or more immunizations, use of PB, pesticides, insect repellents, presence in a chemical-weapons area, and reporting of stressful military service (Kelsall et al. 2004a).
The symptom experience of two deployed cohorts of Gulf War veterans was studied by Boston-based researchers. One of the cohorts, an Army cohort based in Ft. Devens, Massachusetts, was surveyed longitudinally at three times (1991, 1993-1994, and 1997), and underwent psychiatric interviews and other clinical evaluations at the second time (e.g., White et al. 2001). A second deployed cohort from New Orleans was also studied at the second time, as was a non-Gulf War-deployed unit sent to Germany. The Germany-deployed unit was an air ambulance company of National Guard from Maine that had been deployed to Germany for handling wounded personnel evacuated from the gulf.