A study published in today's issue of Neurology shows that veterans of the first Gulf War under the age of 45 have developed ALS, or Lou Gehrig's disease, as much as three times more frequently than those of comparable ages in the general population.
Another study by the Department of Veterans Affairs - published in the same issue of the journal - confirms Dr. Haley's findings using a different method. The VA undertook its study in 1998, one year after Dr. Haley began his investigation at the request of a 35-year-old Gulf War veteran who was diagnosed with ALS a few years after serving in the Persian Gulf. Michael Donnelly and his father, Tom, contacted Dr. Haley after learning that several other young veterans of the war also had the illness.
"This disease occurred in a very abnormal age group - in people in their 20s and 30s instead of 60s and 70s," Dr. Haley said. "It raises the question whether the condition might have been caused - or triggered prematurely - by unusual environmental exposures in the war."
The papers by Dr. Haley and VA researchers represent the first peer-reviewed studies establishing the increased incidence of ALS among Gulf War veterans.
ALS is a neurodegenerative disorder that attacks nerve cells in the brain and spinal cord, leading to muscle weakness in the arms and legs and difficulty speaking, swallowing and breathing, and eventually loss of all muscle function. It affects about 30,000 Americans, and is most commonly associated with baseball Hall of Fame member Lou Gehrig, who retired in 1939 after being diagnosed with the illness. Although Mr. Gehrig died of ALS two years later at age 37, the disorder occurs almost entirely in patients between the ages of 50 and 70, rarely appearing before age 45.
Dr. Haley identified 17 Gulf War veterans - all under 45 - who were diagnosed with ALS by neurologists between 1991 and 1998. None of them have a family history of ALS or other neurodegenerative diseases, and all of the cases have progressed to advanced stages. Eleven have died of the disease.
In order to calculate the number of expected ALS cases among the veterans, Dr. Haley used U.S. vital statistics data from 1979 to 1998. He projected that, under normal circumstances, less than one case of ALS per year would be expected to occur in the Gulf War veteran population in 1991. In subsequent years, as the population aged, the number of cases per year would be expected to increase. The projection for 1998 was 1.38 cases per year. Dr. Haley found that, in fact, there were five observed cases that year.
"The increasing slope of the epidemic curve beginning three years after the Gulf War and still increasing in 1998 further supports a true excess and raises the possibility of an even larger ALS problem in future years in the Gulf War veteran population," said Dr. Haley.
Dr. Haley also found that two-thirds of the veterans in the study had Gulf War syndrome prior to developing ALS. Dr. Haley first described Gulf War syndrome in a series of papers published in January 1997 in the Journal of the American Medical Association (JAMA). His studies traced veterans' mysterious illnesses to damage to deep brain structures from wartime exposure to combinations of chemicals, including low-level nerve agents, that drifted over thousands of soldiers when U.S. forces detonated Iraqi chemical stores. Symptoms of Gulf War syndrome include depression, difficulty concentrating, joint pain, attention and balance deficits, and chronic diarrhea.
In June 1999 Dr. Haley reported in the journal Toxicology and Applied Pharmacology that some soldiers were genetically predisposed to Gulf War syndrome. The study showed that veterans with a gene that causes them to produce high amounts of a protective enzyme called paraoxanase did not get sick after exposure to certain chemicals, while others who produce low amounts of the same enzyme did get sick. Since this enzyme is only protective against chemical nerve agents, the finding links the Gulf War syndrome with nerve-agent exposure, supporting earlier epidemiologic findings published in JAMA. It also explains why some soldiers exposed to the nerve agents in the Gulf did not develop the syndrome.
In another study published in a June 2000 issue of Radiology, Dr. Haley used advanced brain imaging to show that ill Gulf War veterans have brain cell damage in deep brain structures. Multiple studies published in peer-reviewed journals after Dr. Haley's initial studies have corroborated these findings.
The new study shows a more serious brain disease emerging from the Gulf War.
Two years ago, after meeting with Dr. Haley and VA researchers, VA Secretary Anthony Principi approved full benefits for Gulf War veterans diagnosed with ALS based on initial findings of the two studies.
"I am committed to doing research that provides a better understanding of diseases that affect veterans and providing disability compensation as early as possible," Mr. Principi said at the time. "I intend to make certain that VA's medical resources and research capabilities are fully focused on this issue."
Dr. Haley said, "Taking such action before a published study on the subject was a courageous move that allowed ill veterans to get help at the earliest possible date. The publication of these two studies vindicates his decision."
Dr. Haley said it is likely that the ALS cases he studied represent less than half the true number of young Gulf War veterans with the disease. The VA study identified 40 cases in young Gulf War veterans.
The Haley-led study was funded by a grant from the Perot Foundation.
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