title: Complex factors in the etiology of Gulf War illness: wartime exposures and risk factors in veteran subgroups.
abstract: BACKGROUND
  At least one-fourth of U.S. veterans who served in the 1990-1991 Gulf War are affected by the chronic symptomatic illness known as Gulf War illness (GWI). Clear determination of the causes of GWI has been hindered by many factors, including limitations in how epidemiologic studies have assessed the impact of the complex deployment environment on veterans' health.
  
  
  OBJECTIVE
  We sought to address GWI etiologic questions by evaluating the association of symptomatic illness with characteristics of veterans' deployment.
  
  
  METHODS
  We compared veteran-reported wartime experiences in a population-based sample of 304 Gulf War veterans: 144 cases who met preestablished criteria for GWI and 160 controls. Veteran subgroups and confounding among deployment variables were considered in the analyses.
  
  
  RESULTS
  Deployment experiences and the prevalence of GWI differed significantly by veterans' location in theater. Among personnel who were in Iraq or Kuwait, where all battles took place, GWI was most strongly associated with using pyridostigmine bromide pills [odds ratio (OR) = 3.5; 95% confidence interval (CI): 1.7, 7.4] and being within 1 mile of an exploding SCUD missile (OR = 3.1; 95% CI: 1.5, 6.1). For veterans who remained in support areas, GWI was significantly associated only with personal pesticide use, with increased prevalence (OR = 12.7; 95% CI: 2.6, 61.5) in the relatively small subgroup that wore pesticide-treated uniforms, nearly all of whom also used skin pesticides. Combat service was not significantly associated with GWI.
  
  
  CONCLUSIONS
  Findings support a role for a limited number of wartime exposures in the etiology of GWI, which differed in importance with the deployment milieu in which veterans served.
authors.affiliation: Institute of Biomedical Studies, Baylor University, One Bear Place, Waco, TX 76798, USA. Lea_Steele@baylor.edu
authors.forename: Lea
authors.initials: L
authors.lastname: Steele
authors.forename: Antonio
authors.initials: A
authors.lastname: Sastre
authors.forename: Mary M
authors.initials: MM
authors.lastname: Gerkovich
authors.forename: Mary R
authors.initials: MR
authors.lastname: Cook
mesh_terms: D000328:Adult; D016022:Case-Control Studies; D004781:Environmental Exposure; D005260:Female; D047830:Gulf War; D006801:Humans; D007493:Iraq; D007730:Kuwait; D008297:Male; D008875:Middle Aged; D018923:Persian Gulf Syndrome / Q000453:epidemiology / Q000209:etiology*; D010575:Pesticides / Q000633:toxicity; D015995:Prevalence; D011729:Pyridostigmine Bromide / Q000009:adverse effects; D012307:Risk Factors; D014728:Veterans
chemical_list: D010575:Pesticides; D011729:Pyridostigmine Bromide