[Skip to Navigation]
January 15, 1997

Self-reported Exposure to Neurotoxic Chemical Combinations in the Gulf War: A Cross-sectional Epidemiologic Study

Author Affiliations

From the Epidemiology Division, Department of Internal Medicine, University of Texas Southwestern Medical Center at Dallas.

JAMA. 1997;277(3):231-237. doi:10.1001/jama.1997.03540270057027

Objective.  —To identify risk factors of factor analysis-derived Gulf War-related syndromes.

Design.  —A cross-sectional survey.

Participants.  —A total of 249 Gulf War veterans from the Twenty-fourth Reserve Naval Mobile Construction Battalion.

Data Collection.  —Participants completed standardized booklets measuring self-reported wartime exposures and present symptoms.

Main Outcome Measures.  —Associations of factor analysis—derived syndromes with risk factors for chemical interactions that inhibit butyrylcholinesterase and neuropathy target esterase.

Results.  —Risk of syndrome 1 ("impaired cognition") was greater in veterans who reported wearing flea collars during the war (5 of 20,25%) than in those who never wore them (7 of 229, 3%; relative risk [RR], 8.7; 95% confidence interval [CI], 3.024.7; P<.001). Risk of syndrome 2 ("confusion-ataxia") increased with a scale of advanced adverse effects from pyridostigmine bromide (χ for trend, P<.001), was greater among veterans who believed they had been involved in chemical weapons exposure (18 of 108, 17%) than in those who did not (3 of 141, 2%; RR, 7.8; 95% CI, 2.3-25.9; P<.001), and was increased in veterans who had been in a sector of far northeastern Saudi Arabia on the fourth day of the air war (6 of 21, 29%) than in those who had not been (15 of 228,7%; RR, 4.3; 95% CI, 1.9-10.0.0; P=.004). Effects of perceived chemical weapons exposure and advanced adverse effects from pyridostigmine were synergistic (Rothman S, 5.3; 95% CI, 1.04-26.7). Risk of syndrome 3 ("arthro-myo-neuropathy") increased with an index of frequency and amount of government-issued insect repellent containing 75% DEET (N,N-diethylm-toluamide) in ethanol applied during the war (χ2 for trend, P<.001) and with advanced adverse effects from pyridostigmine (χ2 for trend, P<.001).

Conclusion.  —Some Gulf War veterans may have delayed, chronic neurotoxic syndromes from wartime exposure to combinations of chemicals that inhibit butyrylcholinesterase and neuropathy target esterase.