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Original article: http://my.webmd.com/content/article/1728.61308 ---------------------------------------------------------------------------- ---- Researchers Find Large Piece of the Gulf War Syndrome Puzzle Vets' Brain Changes May Lead to Parkinson's Disease Down the Road By Neil Osterweil WebMD Medical News Reviewed by Dr. Jacqueline Brooks Sept. 14, 2000 -- The Persian Gulf War ended a decade ago, but for many veterans, the war's effects still linger. Just last week, the Institute of Medicine released a report saying there wasn't enough evidence to conclude that exposure to certain toxic chemicals is linked to illnesses among Gulf War veterans. Now University of Texas researchers have published a study suggesting a physical explanation for some cases of Gulf War syndrome. Gulf War syndrome -- the Department of Defense prefers to use the less-weighted term "Gulf War illnesses" -- refers to a group of symptoms reportedly experienced by some 225,000 of the nearly 700,000 U.S. troops deployed to the Persian Gulf in 1990. The symptoms include fatigue, discomfort, memory problems, confusion, mood swings, tremors, and other movement problems. The symptoms have been variously chalked up to stress, infections, or reactions to toxic chemicals that the vets were exposed to in the Middle East. In an earlier study comparing 23 ill veterans who served in Operation Desert Storm with 20 healthy veterans from the same unit, Robert W. Haley, MD, and colleagues found that the ill veterans had evidence of brain damage measured by a loss of brain cells. The loss occurred in two parts of the brain responsible for fine-tuned movement, mostly through the production of the chemical dopamine. In the their current study, published in the September issue of The Archives of Neurology, the researchers linked the loss of brain cells to changes in the way the brain produces and uses dopamine. A loss of dopamine is one of the major hallmarks of Parkinson's disease and related movement disorders. "These guys have brain damage that causes abnormal dopamine, and that's causing symptoms," says Haley, chief of epidemiology at University of Texas Southwestern Medical Center (UTSW). "There's been a great deal of minimizing of research in Gulf War veterans saying all this is related to self-reported symptoms, there's no real disease, but this is the first [medical] measure of disease. So Gulf War syndrome is now no longer a bunch of self-reported symptoms: it's brain damage that affects [dopamine] levels." "The observations by Haley and colleagues are a major advance in defining the ... cause of this perplexing and elusive complex of symptoms," writes Roger N. Rosenberg, MD, a neurologist at UTSW and chief editor of the Archives of Neurology, in an editorial accompanying the study. To determine the relationship between the brain damage they had previously seen in these patients and dopamine production, the authors performed a type of brain scan that suggested that dead brain cells were present. They then compared these findings with results of blood tests for dopamine activity in the body. They found that people with fewer brain cells had higher levels of dopamine production. They suspect that the remaining cells have to work extra hard to produce dopamine and may burn out and die prematurely, resulting in the movement problems seen in some of the vets, Haley tells WebMD. In addition to suggesting a physical basis for Gulf War syndrome, the study suggests that the vets who display the brain damage and dopamine abnormality may be at risk down the road for developing Parkinson's disease or similar conditions. Haley gives the example of former world heavyweight boxing champion Mohammed Ali, who suffered repeated brain damage as an occupational hazard, and now suffers the consequences in the form of a Parkinson's-like syndrome. Haley explains that the vets have dead and injured brain cells that will continue to deteriorate and based on precedents, "we would expect that a number of these people will develop premature Parkinson's disease. The current epidemic of Gulf War syndrome in veterans in their 20s to 40s may in turn give rise to a second epidemic [of Parkinson's] in 10, 20 years from now in veterans in their 40s, 50s and 60s." Although he is careful to point out that the predicted Parkinson's disease epidemic is only theoretical, "we have observed a number of young veterans who came back from the Gulf War with tremors that they didn't have before. A tremor is a sign of [brain] injury and dopamine abnormality," Haley tells WebMD. The authors speculate that the brain damage they observed could have been caused by exposure to toxic substances in the environment, either from the nerve gas sarin (which was documented as being present in the air on at least one occasion), high doses of pesticides, or from adverse reactions to substances used to protect soldiers against chemical warfare agents. But a radiologist who reviewed the paper prior to publication tells WebMD the researchers are hampered by a chicken-and-egg problem. "Whether increased dopamine activity led to [nerve] damage or [nerve] damage led to increased dopamine levels is uncertain," says Michael W. Weiner, MD, director of the MRS Laboratory at the Veterans Affairs Medical Center in San Francisco. "On the other hand," he says, "the data is interesting, and it does tend to support the idea that there is a change in the brain of some patients with Gulf War syndrome, and that is an important finding, because up until now there has been only very soft evidence that there is biologically anything wrong with Gulf War veterans." Weiner cautions that the study sample was very small, but he also notes that he and his colleagues have been able to reproduce some of Haley's original findings. "The important thing is that this work be followed up to determine whether there really is a biological basis to the symptoms of Gulf war illness at least in some of the patients," Weiner says. "We owe that our vets." © 2000 WebMD Corporation. All rights reserved.