April 28, 2004 -- Military service in any branch or during any period may increase the risk of ALS (amyotrophic lateral sclerosis), according to a new study.
Researchers found that men who served in the military were 60% more likely to develop ALS, also known as Lou Gerhig's disease, than men who did not serve in the military.
The exact cause of ALS is unknown. The disease causes a gradually weakening of the muscles and usually leads to death within three to six years. Men are affected slightly more than women and ALS is most common among middle-aged and older adults.
The results of the study were presented today at the American Academy of Neurology 56th Annual Meeting in San Francisco.
ALS Linked to Military Service
"Two recent studies suggested that the risk of ALS is increased among Gulf War veterans," says researcher Marc Weisskopf, PhD, of the Harvard School of Public Health, in a news release. "We wanted to find out whether military service prior to the Gulf War was associated with an increased risk of ALS."
In the study, researchers looked at the relationship between military service and ALS deaths among a large database of men surveyed by the American Cancer Society in 1982. The study included 268,258 men who served in the military and 126,414 who did not.
There were 274 deaths from ALS reported in these men from 1989 through 1998. After adjusting for age and smoking status, which has been suggested as a risk factor for ALS, researchers found men who had served in the military were 60% more likely to have died from ALS than those with no military record.
However, men who served in the military had lower death rates from other causes.
The increased ALS risk was similar among men who served in the Army or National Guard and the Navy or the Air Force. Men who served in World War II, Korean War, or Vietnam War all had a higher risk of ALS, although there were not enough men who had served in Vietnam for the numbers to be statistically significant.
"This study shows that the increased risk of ALS among military personnel does not appear to be specific to service during the Gulf War," says Weisskopf. "More research is needed to confirm this increased risk for men in military service in general, and eventually to determine its causes."