Multiple Sclerosis Centers of Excellence
Combat-Related Chemical Exposure and the Link to Multiple Sclerosis and Other Neurological Diseases
Many studies have looked at how war affects the health of military personnel. Right now, several research studies are checking whether there is a link between war and certain illnesses. Web links to resources about combat-related illness and injury are listed at the end of this article.
This type of research is hard to do. Usually, researchers notice that a group of service members or Veterans with a disease share a similar military history. Then someone asks: is this disease related to that military history? To find out, researchers must look back in time to learn about the military history and exposures of those affected. They often must rely on questionnaires and military records that were not designed for this kind of research. They must also identify who has the disease and who does not, define the suspected exposures, confirm the disease did not happen before military service, and determine who was exposed and who was not.
To show that an exposure causes a disease, researchers must show that people who were exposed get the disease at a higher rate than those who were not. For example, Gulf War Veterans were checked for several neurological diseases. ALS was slightly more common in Gulf War Veterans than in those who did not serve in the Gulf War. However, multiple sclerosis (MS) was not more common in Gulf War Veterans (Barth et al. Am J Ind Med. 2009 Sep;52(9):663-70).
Two studies have looked specifically at the possible link between combat or combat-related exposures and the risk of developing MS. The first used a large group of Gulf War era Veterans who were service-connected for MS (Wallin et al. Neuroepidemiology. 2014;42(4):226-34). Data from the Department of Defense on exposure to oil well fires and the destruction of chemical weapons sites was reviewed. Medical records were also checked to find those who developed MS after deployment. Veterans deployed to areas with these exposures actually had less MS than those who were not deployed. However, we believe this may be due to the "healthy soldier effect." This means that only the fittest soldiers - those least likely to develop MS - are chosen for deployment.
The second study looked at new MS cases in active-duty personnel. It asked whether being sent to a combat zone led to higher rates of MS compared to those not deployed (Williams et al. MSMR. 2017 Aug;24(8):2-11). This study did not look at any specific exposure. Even so, it found that active-duty service members deployed to a combat zone had a 22.4% higher rate of MS than those not deployed. The results from these two studies, along with others, are mixed. They do not provide clear evidence that combat-related exposures raise the risk of developing MS.
At this time, there is no evidence of a link between MS and Agent Orange, radiation exposure, depleted uranium, or Gulf War service. However, if you think you may have been exposed to Agent Orange and are experiencing health symptoms, we recommend calling the Agent Orange hotline at 800-749-8387 or visiting the VA Agent Orange website.
Additional Information
- Compensation: Veterans Exposed to Agent Orange
- National MS Society Webinar: MS Risk and Prevalence
- War Related Illness
- VA Vets.gov Agent Orange
Based on an article by William J. Culpepper II, PhD, MA.
