WEDNESDAY, April 28, 2004 (HealthDayNews) -- New evidence has emerged to suggest that all men who serve in the military are at an increased risk of developing Lou Gehrig's disease.
The higher odds of getting the disease, also known as amyotrophic lateral sclerosis (ALS), did not appear to be associated with a particular branch of the military or particular time period. Previous research found a similar risk for Gulf War veterans.
"In looking for some agent, we should perhaps not be focusing on the Gulf War but looking for those that are common across eras and military experiences. What exactly those are is tough," said study author Marc Weisskopf, a research associate at the Harvard School of Public Health. He will present the findings on April 28 at the American Academy of Neurology's annual meeting in San Francisco.
This appears to be the first study to detect a wider association between military service and ALS, and seems to make it less likely that a military connection with the disease is an anomaly. "Our study has its own limitations, but certainly the mounting evidence would suggest that this is not a fluke," Weisskopf added.
And although "any clue as to some environmental trigger in this disease is a helpful thing," said Dr. Stephen Scelsa, director of the neuromuscular division and the ALS Center at Beth Israel Medical Center in New York City, the full significance of the finding is not yet clear.
ALS is a progressive, fatal neurological disease that affects as many as 20,000 Americans, with 5,000 new cases each year in the United States, according to the National Institutes of Health.
Two recent studies had indicated an increased risk of ALS among Gulf War veterans.
Weisskopf and his colleagues wanted to see if that risk extended to more people. Between 1989 and 1998, he and his colleagues followed 268,258 men who had served in the military and 126,414 who had not. During this time, 274 men died of ALS. All of the participants were part of the American Cancer Society's Cancer Prevention Study II, begun in 1982. Dates of entering military service ranged from 1906 to 1982.
Overall, men who had served in the military had a lower death rate, yet they were 60 percent more likely to develop ALS than men who had not served in the military. The increased risk was similar in the Army, National Guard, Navy and Air Force.
There is no clear answer as to why this might be the case. People have variously postulated that risk might be elevated due to heavy metal exposure (particularly lead), extreme physical exertion, and electrical work (including shocks), Weisskopf said.
"This hasn't been shown with rigorous scientific data, but this disease does occur in people who are athletic, like Lou Gehrig," Scelsa added. "There may be people in the military who do a lot of physical work and strain, and that may predispose them to the disease, but I think the answer is just not in."
Weisskopf and his colleagues are seeking further funding to try to find some of these answers, and also to look into the fact that men and women who regularly take vitamin E seemed to be less likely to develop ALS.
"Our first order of business is trying to get some money to be able to go in and code death certificates and follow up further [back] beyond 1988," Weisskopf said. He then wants to look in more detail at potential exposures within specific branches of the military. That would require collaborating with the armed services.
More information
For more on ALS, visit the ALS Association or the National Institutes of Health.
