Causes of Gulf War Illness are complex

Gulf War Illness (GWI) -- the chronic health condition that affects about one in four military veterans of the 1991 Gulf War -- appears to be the result of several factors, which differed in importance depending upon the locations where veterans served during the war, according to a Baylor University study funded by the U.S. Department of Defense.

Published in the journal Environmental Health Perspectives, the study investigated links between GWI and veterans' locations during the war. GWI was most prevalent in veterans who served in forward areas of Iraq and Kuwait, where it was most strongly associated with use of a medication given to 1991 Gulf War troops to protect them from the effects of nerve agents. For personnel who remained in support locations, GWI was significantly associated only with pesticide use during the war.

"Understanding the causes of GWI has presented a complex puzzle in the 20 years since the Gulf War," said Dr. Lea Steele, Baylor epidemiologist and lead author of the study. "Many of the nearly 700,000 U.S. veterans who served in that war encountered different levels and combinations of potentially hazardous substances."

The study found that GWI prevalence was nearly six times higher in veterans who served in Iraq or Kuwait, where all ground battles took place during the 1991 conflict, compared to veterans who remained on board ship during the war. For troops in the high-risk areas, GWI prevalence was 3.5 times greater in the subgroup that used pyridostigmine bromide pills, or PB, compared to those who did not use PB, which was issued by the military as a protective measure in the event of a nerve gas attack. GWI was also increased for forward-deployed personnel who reported being near exploded SCUD missiles, smoke from the Kuwaiti oil fires, or pesticide use.

"Twenty years after Desert Storm, it is essential to understand why veterans became ill," Steele said, "to better address the biological mechanisms that underlie veterans' symptoms and to prevent this problem from happening in the future."