WASHINGTON -- Military service, particularly in the Gulf War, may be linked to the development of Lou Gehrig's disease, the Institute of Medicine said yesterday.
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 patients die of respiratory failure within a few years. ALS affects between 20,000 and 30,000 Americans at any given time .
According to the report, 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, chairman of the committee that wrote the report.
"Because ALS occurs so rarely, any individual veteran's chances of developing the disease are still low," he added.
Johnson is a professor of neurology at Johns Hopkins University's school of medicine in Baltimore.
The individual studies had been previously reported, and the Veterans Affairs Administration asked the institute to review what was known about the illness and provide a new overview. The Institute of Medicine is an arm of the National Academy of Sciences, an independent research organization chartered by Congress to provide scientific advice.
"The secretary will convene senior VA medical experts to study this report and make recommendations to the department," VA spokeswoman Lisette Mondello said yesterday.
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 nonveteran population for ALS.
But some of those studies may have understated the number of ALS cases among nonveterans, and the institute said others were less useful because of limitations in the methods they used.