Neuropsychological function in Gulf War veterans: relationships to self-reported toxicant exposures.

Background The present study was aimed at (1) exploring evidence of central nervous system (CNS) dysfunction among Gulf War (GW) veterans on neuropsychological tests and (2) examining whether performance on neuropsychological tests was related to specific neurotoxicant exposures experienced in the Gulf. Methods The GW-deployed groups were selected using stratified random sampling methods from two distinct cohorts of GW veterans. A comparison group that had been called up for GW service but deployed to Germany rather than the Gulf also was examined. Neuropsychological function was assessed using a pre-determined battery chosen to include tests known to be highly sensitive to the behavioral effects of the neurotoxicants thought to have been present in the Gulf. Results Self-reported exposures were related to neuropsychological test performance controlling for post-traumatic stress disorder, major depression, and other known covariates of neuropsychological test performance. Results showed that GW-deployed veterans performed more poorly than the Germany-deployed veterans on several specific neuropsychological tests, but after adjustment for multiple comparisons, only the differences in mood complaints remained significant. Within the GW-deployed group, self-reported exposure to chemical warfare agents was associated with poorer performance on cognitive tests involving specific functional domains. Conclusions Results provide evidence that there are subtle differences in CNS function among GW-deployed veterans who report chemical warfare agent exposure while in the GW theater. Am. J. Ind. Med. 40:42–54, 2001. © 2001 Wiley-Liss, Inc.