Gulf War Syndrome and Lou Gehrig’s Disease
Back in December, the Defense and Veterans Affairs Departments announced that it had finally(!) found a disease that seemed to be positively correlated with serving during the Persian Gulf War. As the headlines in newspapers across the country announced, soldiers who served in the Persian Gulf War were twice as likely to contract Lou Gehrig’s Disease (ALS) than soldiers who did not serve in the Persian Gulf War. So there really is a Gulf War Syndrome after all right? Not so fast.
First, although it trumpeted this study, the Defense and Veteran Affairs Department still have not subjected the study to peer review. The announcement that the government would provide special compensation for Persian Gulf war veterans with ALS was absurdly premature given the lack of a formal peer review.
Second, the claims of increased incidence of ALS rely on an extremely small number of cases. Of 700,000 soldiers who fought in the Persian Gulf War, there were only 40 identified cases of ALS, compared to 67 cases among 1.8 million soldiers who served at the same time but not in the Persian Gulf War. This yields a rate of 3.5 cases per million for non-Gulf soldiers compared to a rate of 6.7 cases per million for those who served in the Persian Gulf. Such low numbers of cases, however, means that normal statistical variations can have enormous affects.
Third, this appears to likely be the explanation considering that not all soldiers have the increased incidence. There is no additional incidence of ALS, for example, among British soldiers who served in the Persian Gulf compared to British soldiers who served elsewhere. Moreover, the additional incidence among U.S. soldiers varies oddly across branches.
There is no difference in incidence, for example, among Navy and Marine Corps veterans, but Air Force Gulf veterans were 2.7 times more likely to develop ALS and Army veterans twice as likely to develop ALS.
As Richard Green of the United Kingdom’s Motor Neurone Disease Association told New Scientist,
You would expect to find 33 cases of ALS in a group the size of the veterans group — and about 85 in a group the size of the non-Gulf War group. So you could also ask the question: why is the number of cases so low in the non-Gulf War group? That is the problem with these kinds of studies and these kinds of statistics. You are dealing with such small numbers of cases that a handful of extra cases can distort the final figures.
Add to that the fact that two previous studies of ALS and Gulf War veterans found no increased risk, and this study means far less than the Pentagon would have you believe.
Source:
US links fatal disorder to Gulf War service. Emma Young, New Scientist, December 1, 2001.
U.S. reports disease link to Gulf War. Sheryl Gay Stolberg, The New York Times, December 11, 2001.
Tags: Gulf War Syndrome