ABSTRACT
I. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 262 II. The Population at Risk . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 265
III. Outcomes in the Population at Risk . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 266 A. Mortality . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 267 B. Morbidity . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 269 C. Symptom Prevalence . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 270 D. Reproductive Outcomes. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 271
IV. Subsets of the Population at Risk: Symptom-Based Clusters . . . . . . . . . . . 272 A. 123rd ARCOM. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 273 B. Air National Guard . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 274 C. Seabees . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 274 D. Reproductive Effects . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 275
V. Subsets of Population at Risk: Common Exposures . . . . . . . . . . . . . . . . . . 276 A. Infectious Diseases . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 276 B. Immunizations, Pesticides, and Occupational Exposures . . . . . . . . . . . 277 C. Depleted Uranium . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 278 D. Oil Well Fires. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 279 E. Chemical and Biological Warfare Agents . . . . . . . . . . . . . . . . . . . . . . . 279 F. Khamisiyah, Iraq . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 280 G. Mixed Exposures and Synergistic, Additive, or Other
Combined Effects . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 283 VI. Subsets Enrolled in Registries. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 283
VII. Outcomes in Subpopulations in Registries . . . . . . . . . . . . . . . . . . . . . . . . . 285 VIII. Is There a Single PGW Syndrome? The Problem
with Case Definition . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 289
IX. Future Research Directions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 290 X. Association vs. Causation in Environmental Epidemiology . . . . . . . . . . . . 291
Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 295 References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 295
Ten years following the Persian Gulf conflict, uncertainty remains regarding potential exposures, health risks, and adverse outcomes in the 697,000 U.S. troops deployed to Operations Desert Shield/Desert Storm. While this was not the first wartime cohort to report medically unexplained symptoms, it is certainly the most studied. Somatic complaints such as fatigue, shortness of breath, headache, sleep disturbance, forgetfulness, and impaired concentration have been reported following armed conflicts since the Civil War (Table 9.1).1 The authors described two general categories of war-related illness-a poorly understood group thought to be associated with physiological disease, and another group of psychological illnesses attributed to wartime stress. “War syndromes have not been consistently defined or identified by a pathognomonic physical sign or laboratory abnormality. As a result, the diagnosis of a physiological or psychological illness in individual patients has been imprecise and has depended on self-reported symptoms and the impression of the examining physician.”
