Military service, particularly in the Gulf War, may be linked to development of Lou Gehrig’s disease, the Institute of Medicine said Friday.
The evidence, however, is limited and inconsistent, the Institute said.
The degenerative nerve disease, formally known as amyotrophic lateral sclerosis, or ALS, gradually destroys the ability to control movement. Patients lose their ability to move or speak, but their minds remain unaffected. Most victims die of respiratory failure within a few years.
According to the report, released as Veterans Day was being observed, five studies have been done on the subject.
Three indicated a higher rate of ALS among veterans of the 1990-91 Gulf War, one found a link to veterans who served prior to that war and one found no link at all.
“The evidence base to answer the question of whether military service increases a person’s chances of developing ALS later in life is rather sparse, so we could not reach more definitive conclusions at this time,” said Richard T. Johnson, chair of the committee that wrote the report.
Still a small risk
“Because ALS occurs so rarely, any individual veteran’s chances of developing the disease are still low,” he added. ALS affects between 20,000 and 30,000 Americans.
Johnson is a professor of neurology at the Johns Hopkins University school of medicine in Baltimore.
The individual studies had been previously reported, and the Department of Veterans Affairs asked the Institute to review what was known and provide a new overview.
In 2001, then secretary of Veterans Affairs Anthony J. Principi ordered that disability compensation be made available to veterans who served in the Gulf War in 1990-1991, who later developed ALS. Such compensation is not available to other veterans.
Double the risk in Gulf War vets
In its analysis, the Institute said three studies indicated the chance of developing ALS as much as doubles for Gulf War veterans. Another study concluded that veterans who served prior to that war had 1.5 times the rate of the non-veteran population for ALS.
But some of those studies may have understated the number of ALS cases among non-veterans, and the Institute said others were less useful because of limitations in the methods they used.
A fifth study found no relationship between military service and ALS.
Overall, the Institute concluded, “There is limited and suggestive evidence of an association between military service and later development of ALS.”
Hunt for the cause
The report called for more research to confirm this relationship and to determine the cause of any increased risk — which it said could include chemicals, involvement in traumatic events, intensive physical activity or other substances or activities.
Officials of veterans organizations could not immediately be reached for comment on the report.
ALS got the name Lou Gehrig’s disease from the famed New York Yankees baseball player who died from it. Another well-known victim is English physicist Stephen Hawking, author of “A Brief History of Time.” Hawking uses a wheelchair and communicates using a computer and voice synthesizer.
Between 5 percent and 10 percent of ALS cases are thought to be inherited; the causes of the rest remain unknown.