Respiratory conditions such as asthma, bronchitis, chronic obstructive pulmonary disease, and various symptoms consistent with respiratory disease, such as wheezing and shortness of breath, have consistently been self-reported more frequently by deployed Gulf War veterans than controls. Exposures of concern in the theater include smoke from oil-well fires, high levels of ambient dust, pesticide sprays, and nerve gas exposure. A primary study met the committee’s criteria for methodological rigor (Chapter 2) and used objective measures of pulmonary function or death from respiratory disease. In a secondary study, the determination of a respiratory illness was based on veterans’ self-reports of symptoms or self-reported physician-diagnosed conditions. Primary studies are summarized in Table 4-8.
The Volume 4 committee identified five primary studies that undertook to explore the association between pulmonary conditions and deployment to the Gulf War. Two of these studies were analysis of data from the 1995 National Health Survey of Gulf War Era Veterans and Their Families (Kang et al., 2000) conducted by the VA on 1061 Gulf War veterans and 1128 nondeployed veterans. This population was derived from a cohort of randomly selected participants from the previous 1995 study who had completed the earlier mailed questionnaire on self-reports of health conditions. Eisen et al. (2005) reported on the prevalence of self-reported asthma, bronchitis, and emphysema and found no significant differences between the two groups after adjusting for smoking and demographic variables. In a further study that applied spirometry and symptom interviews to a random selection of 1036 Gulf War deployed veterans compared with 1103 nondeployed US veterans, Karlinsky et al. (2004) found that only a history of smoking and wheezing among the respiratory outcomes studied were significantly elevated in the deployed veterans. No significant difference in the number of self-reported physicians’ visits or hospitalizations for respiratory disorders was seen between the groups. Spirometric measurements also showed no significant difference between the two groups. The study did not report participation rate. The study also looked at the effect of potential exposure to the Khamisiyah nerve gas releases by selectively comparing veterans deployed into the geographic areas potentially affected by the release. No significant differences were noted in the measured pulmonary functions of these veterans when compared to nondeployed controls or veterans who were unlikely to have been exposed to the nerve gas.
Gray et al. (1999a) also found that between 527 Gulf War Seabees and 970 nondeployed Seabees, pulmonary function parameters (force vital capacity [FVC] and forced expiratory volume in 1 second [FEV1]) showed no significant difference between the two groups, whereas respiratory symptoms (cough: OR 1.8, 95% CI 1.2-2.8; shortness of breath: OR 4.0; 95% CI 2.2-7.3) were significantly more common among deployed veterans compared with nondeployed veterans after adjustment for age, height, race, and smoking status.
Two studies of non-US Gulf War era veterans included an examination of respiratory outcomes. Australian Gulf War veterans were studied by Kelsall et al. (2004b) for respiratory outcomes. The prevalence of respiratory symptoms such as wheezing, chest tightness, cough, and dyspnea was higher (ORs ranged from 1.2-1.8; 95% CIs ranged from 0.9 to 2.3) among 1456