only study that used a clinician-administered interview and reported kappa values for inter-rater reliability. It was also unique in that it compared rates of unexplained physical disability between veterans who served in the Gulf and veterans who served in other wars. The main result was that a great majority of disabled Gulf War veterans (76%) did not have a formal psychiatric disorder. Indeed, the prevalence of mental disorders was similar for veterans disabled after the Gulf War and veterans disabled after other Gulf War-era deployments (prevalence of any psychiatric disorder 24% vs 19%); 12% of nondisabled Gulf War veterans had any psychiatric disorder. Compared with disabled veterans from Bosnia or era veterans, disabled Gulf War veterans were no more likely to have an alcohol-related disorder (OR 1.9, 95% CI 0.4-9.1), mood disorder (OR 1.0, 95% CI 0.3-3.2), anxiety disorder (OR 1.4, 95% CI 0.4-4.3), PTSD (OR 1.1, 95% CI 0.1-9.1), sleep disorder (OR 1.1, 95% CI 0.4-3.2), or any psychiatric disorder (OR 1.3, 95% CI 0.5-3.4); only the presence of somatoform disorder approached significance (OR 3.1, 95% CI 1.0-9.6). When compared to nondisabled Gulf War veterans, disabled Gulf War veterans were at increased risk only for anxiety disorders (OR 6.8, 95% 1.4-33.4). The authors inferred that psychiatric disorders do not explain the elevation in self-reported ill health in Gulf War veterans.
This study also compared disabled with nondisabled Gulf War veterans. There was a more than twofold increase (16% for disabled vs 7% for nondisabled) in undifferentated somatoform disorder (OR 3.3, 95% CI 0.8-13.8), which represents the presence of one or more unexplained medical symptoms. Also, the overall prevalence of psychiatric disorders was twofold higher (24% in disabled Gulf War veterans vs 12% in nondisabled Gulf War veterans; OR 2.4, 95% CI 0.8-7.2). It should be noted, however, that the prevalences of some specific disorders—notably PTSD and alcohol-related disorders—were not significantly different between the disabled and nondisabled veterans.
Ten years after the war, Fiedler and colleagues (2006) conducted telephone interviews using the CIDI Short Form. In a random sample drawn from all US troops deployed and not deployed to the Gulf War from August 1990 to July 1991, the response rates were 59% for deployed and 51% for nondeployed veterans. This study used the largest random sample of US Gulf War deployed and era veterans in which a layperson-administered structured interview was used to assess 12-month prevalences of psychiatric disorders. When compared with era veterans, those deployed to the Gulf War had significantly higher prevalences of psychiatric disorders. Thus, there were increases in the prevalence of MDD (14.2% in deployed vs 7.2% nondeployed male veterans and 25.3% vs 11.8% for deployed vs nondeployed female veterans); PTSD (3.4% vs 0.7% for male veterans and 4.0% vs 2.2% for female veterans); and of substance dependence (5.3% vs 3.3% male veterans and 2.7% vs 2.2% in female veterans). Comparing all deployed veterans with nondeployed veterans, the OR for anxiety disorder was 1.81 (95% CI 1.34-2.45) and the OR for MDD was 2.07 (95% CI 1.50-2.85). Lower rank, female gender, and divorced or single marital status were significant independent predictors of psychiatric disorders other than substance use disorders. For substance use disorders, being male, having lower rank, divorced or single marital status, and deployment other than to the Persian Gulf were significant independent predictors.
These results are consistent with those found by Ikin et al. (2004) who used the CIDI to assess 1381 deployed Australian Gulf War veterans and 1377 nondeployed veterans. They also reported elevated rates of any depressive disorder (OR 1.7, 95% CI 1.3-2.1) and any anxiety disorders (OR 2.9, 95% CI 2.0-4.2), specifically MDD (OR 1.6, 95% CI 1.3-2.0), PTSD (OR 3.9, 95% CI 2.3-6.5), OCD (OR 5.6, 95% CI 1.7-24.2), or social phobia (OR 3.1, 95% 1.6-6.0), but no cases of somatization disorder. It is important to note that somatization disorder is not a