Gulf War Illness (GWI) is a debilitating multi-symptom condition that affects nearly a third of 1990-91 Gulf War (GW) veterans. Symptoms include chronic pain, debilitating fatigue, gastrointestinal issues, and cognitive decrements. Prior studies have documented reduced cognitive functioning in this affected population, particularly in the areas of memory, attention and response inhibition. To date, research has focused on cognitive functioning in male and female veterans together. Very limited research has reported on GW women's cognitive functioning separately mostly due to scarcity of data on women veterans. In this study, we had the unique opportunity to utilize a newly combined neuropsychological test dataset from women GW veterans in the Boston, Biorepository and Integrative Network (BBRAIN) for GWI. The aim was to compare neuropsychological outcomes with toxicant exposures in women veterans with and without GWI.

Cognitive data from the BBRAIN biorepository was used for this study. The sample consisted of 62 women veterans who were deployed to the Persian Gulf War from 1990-91. Neuropsychological test scores included the Conners Continuous Performance Test Third Edition (CPT3), Delis-Kaplan Executive Function System (D-KEFS) Color-Word Interference, and the California Verbal Learning Test Second Edition (CVLT-II). War-related exposure to chemical weapons, anti-nerve gas pills and pesticides were measured by a self-reported survey. For analysis, war-related exposure was classified into three groups: controls with 0-6 days of exposure; cases with 0-6 days of exposure and cases with 7 or more days of exposure. Multiple linear regression modeling was used to measure differences in neuropsychological scores across the three groups by each war-related exposure.

After adjusting for age, education and other exposures, an increase in duration of exposure to pesticides was significantly associated with worse CPT3 commission errors, fewer words correct in the CVLT-II trials 1-5, and an increase in self-corrected errors on DKEFS Color-Word Interference Test Trials 1, 2 and 4 (p<0.05). More days reported hearing chemical alarms and seeing smoke from oil well fires was significantly associated with fewer words correct on all CVLT-II trials, and more self-corrected errors on Color-Word Interference Trials 2 and 4 (p<0.05). An increase in exposure duration to pyridostigmine bromide anti-nerve gas pills was associated with fewer words correct on the CVLT-II learning Trials 1-5 and short delay recall and an increase in self-corrected errors on Color-Word Interference Trials 2, 3, and 4 (p<0.05). When associations were adjusted for PTSD, all significant associations stayed constant (p<0.05).

In this study, women veterans with GWI who had higher levels of exposure to pesticides, oil well fires and who took more antinerve gas pills during the war are showing increased learning difficulties and more deficits in attention and response inhibition. Future research should examine if similar patterns of neuropsychological symptoms are also present in male GW veterans with higher war-time related toxicant exposures.