Epidemiologic Study of the Occurrence of Amyotrophic Lateral Sclerosis (ALS) Among Gulf War Veterans

In June 1999, the Department of Veterans Affairs and U.S. Department of Defense requested that CDC assist in a study of amyotrophic lateral sclerosis (ALS) among Gulf War veterans. ALS is a fatal neurodegenerative disease that destroys the brain and spinal cord nerve cells that control muscle movement. As the brain and spinal cord nerve cells die, muscles weaken and shrink, and rapid severe paralysis occurs. Neither a cause nor a cure for ALS is known at this time. This investigation of ALS was initiated to determine if there is a higher than expected incidence of ALS among veterans of the 1991 Gulf War and to examine possible risk factors for the disease. CDC’s Environmental Health Laboratory conducted laboratory analyses of blood and urine specimens to look for signs of exposure to heavy metals. Initial results found military personnel who were deployed to the Gulf region during the 1991 Gulf War experienced a greater post-war risk of ALS than those who were not deployed to the Gulf. Among approximately 2.5 million eligible military personnel, 107 confirmed cases of ALS were identified (an overall occurrence of 0.43 per 100,000 persons per year). Overall, the attributable risk associated with deployment was 18% (95% CL = 4.9% to 29.4%). Findings regarding exposure to heavy metals are pending.


Horner RD, Kamins KG, Feussner JR, Grambow SC, Hoff-Lindquist J, Harati Y, et al. Occurrence of amyotrophic lateral sclerosis among Gulf War veterans. Neurology 2003;61(6):742–9.

Page last reviewed: October 29, 2010 (archived document)