SUMMARIES FOR PATIENTS

Can Antibiotics Cure Gulf War Veterans' Illnesses?

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The summary below is from the full report titled "Benefits and Harms of Doxycycline Treatment for Gulf War Veterans' Illnesses. A Randomized, Double-Blind, Placebo-Controlled Trial." It is in the 20 July 2004 issue of Annals of Internal Medicine (volume 141, pages 85-94). The authors are S.T. Donta, C.C. Engel Jr., J.F. Collins, J.B. Baseman, L.L. Dever, T. Taylor, K.D. Boardman, L.E. Kazis, S.E. Martin, R.A. Horney, A.L. Wiseman, D.S. Kernodle, R.P. Smith, A.L. Baltch, C. Handanos, B. Catto, L. Montalvo, M. Everson, W. Blackburn, M. Thakore, S.T. Brown, L. Lutwick, D. Norwood, J. Bernstein, C. Bacheller, B. Ribner, L.W.P. Church, K.H. Wilson, P. Guduru, R. Cooper, J. Lentino, R.J. Hamill, A.B. Gorin, V. Gordan, D. Wagner, C. Robinson, P. DeJace, R. Greenfield, L. Beck, M. Bittner, H.R. Schumacher, F. Silverblatt, J. Schmitt, E. Wong, M.A.K. Ryan, J. Figueroa, C. Nice, and J.R. Feussner, for the VA Cooperative #475 Group.

What is the problem and what is known about it so far?

Many veterans of the first Gulf War have had a variety of chronic physical and mental symptoms (Gulf War veterans' illnesses, or GWVIs) in the years since that war. Symptoms of GWVIs are often poorly defined and are not limited to any one organ in the body. They include fatigue, joint and muscle pains, night sweats, rashes, headaches, diarrhea, and problems with thinking clearly or with memory.

Doctors don't know what causes GWVIs. Possible causes include psychological trauma and exposure to toxic chemicals or to fallout from destroyed nuclear reactors. Blood tests suggest that as many as 40% of veterans with GWVIs may have chronic bacterial infections. Mycoplasma species are some of the bacteria most commonly detected. We don't know whether chronic infection with these bacteria actually causes some GWVIs, and we don't know how patients with chronic Mycoplasma infections typically do over time. However, we do know that antibiotics can kill these bacteria. Thus, if Mycoplasma infection causes some GWVIs, antibiotics might help.

Why did the researchers do this particular study?

To see if long-term treatment with an antibiotic (doxycycline) that fights Mycoplasma infections improves symptoms of veterans with GWVIs.

Who was studied?

491 veterans with GWVIs who had Mycoplasma species detected in their blood. All had fatigue; pain in their muscles, tendons, joints, or bones (musculoskeletal pain); or memory and thinking problems.

How was the study done?

Participants were U.S. veterans who had served in the first Gulf War between August 1990 and August 1991. All had developed symptoms of GWVIs after deployment and had DNA tests that showed Mycoplasma infection in their blood. The veterans were randomly assigned to take doxycycline (200-mg pills) or placebo (matching dummy pills) once a day for 12 months. Neither the researchers nor the veterans knew who got doxycycline or placebo. Veterans answered questions about physical and mental function and pain and fatigue every 3 months for a year and then again at 18 months. They also had repeated blood tests to check for Mycoplasma infection. The researchers then compared symptoms and results of blood tests between groups.

What did the researchers find?

The groups had no differences in physical or mental function at 12 and 18 months. Pain and fatigue symptoms also remained similar between groups. Veterans given doxycycline had nausea and sun sensitivity more often than did those given placebo. At 1 year, about 75% of the veterans in both groups no longer had Mycoplasma infection in their blood.

What were the limitations of the study?

Many veterans stopped taking their pills about 6 months into the study.

What are the implications of the study?

Doxycycline probably doesn't benefit veterans with GWVIs and may harm them. Mycoplasma infection probably doesn't cause GWVIs.