Steele (2000) conducted a telephone survey of veterans who were Kansas residents and had served during the Gulf War. Of 2211 locatable and eligible veterans, 2030 agreed to participate (92%). Fifty were eliminated because their self-reported deployment status could not be verified. A total of 1548 Gulf War deployed veterans and 482 nondeployed veterans were interviewed about the presence of physician-diagnosed or physician-treated disorders with new onset after the Gulf War. Respiratory disorders were more commonly reported among deployed than nondeployed. Gulf War deployed veterans were twice as likely to report suffering from asthma (OR 2.08, 95% CI 1.02-4.26) and were almost 5 times as likely to report suffering from lung disease (OR 4.77, 95% CI 1.14-20.04). The study adjusted for sex, age, income and education level and suffered from a slight differential participation rate between groups (93% in deployed veterans vs 88% nondeployed veterans).
Proctor et al. (2001a) compared responses to questionnaires between 148 Gulf War deployed veterans of the Fort Deven’s cohort, and 50 Germany deployed veterans. The authors found that Gulf War deployed veterans reported more chronic respiratory allergies (16% vs 13%) and more chronic lung problems (11.8% vs 6.5 %). Neither of these differences reached statistical significance, and no adjustments were made in the comparisons.
McCauley et al. (2002), using a telephone survey, interviewed three groups of US Gulf War veterans with different deployment experiences. These included Gulf War deployed veterans in proximity to the Khamisiyah detonations, veterans deployed to the gulf during the war but not in proximity to the Khamisiyah detonations, and veterans who were on active duty during, but not deployed to, the Gulf War. The authors found a nonsignificant excess in self-reported diagnosis of lung disease among deployed versus nondeployed veterans (OR 1.8, 95% CI 0.8-4.1) and no excess among Khamisiyah exposed versus Khamisiyah nonexposed veterans (OR 0.3, 95% CI 0.2-0.8).
In a mailed symptom survey to a sample of veterans from the National Health Survey of the Gulf War Era Veterans and Their Families conducted in 1995 (Kang et al., 2000), Kang et al. (2009) found a significant excess of self-reports of physician-diagnosed emphysema or chronic bronchitis and asthma among 6111 randomly surveyed Gulf War veterans when compared to 3859 nondeployed era veterans. The study suffered from a very low response rate (34% overall) and lacked a mechanism for verification of self-reports.
Statistics Canada (2005) conducted a mortality follow-up study of Canadian Gulf War veterans and compared them to a reference group of randomly selected Canadian veterans eligible but not deployed to the Gulf War and to the general Canadian population. There were 5117 members in the deployed cohort and 6093 members in the nondeployed population. Probabilistic matching of the military records of the cohorts to mortality records from the Canadian Mortality Data Base was conducted. The study authors estimated the study power to be 80% to find a 60% increase in total mortality; however, there were insufficient deaths from respiratory disease (ICD-9, code 460-519) to make a meaningful comparison between veteran cohorts or with the general population.
Kang and Bullman (1996) examined standardized mortality rates (SMRs) for multiple causes of death among Gulf War veterans up to September 1993 compared to the general US population and to nondeployed veterans. They found a significant decrease in deaths due to respiratory illness (SMR 0.14, 95% CI 0.07-0.23) when Gulf War veterans were compared to the US population and a slight but insignificant increase when compared to nondeployed veterans. These observations were based on very small numbers including only 14 deaths in both the deployed and nondeployed groups. A second study updated the same cohort for mortality