Veterans of the Gulf War are more than twice as likely to have medically unexplained symptoms known as "multisymptom illness" (MSI), compared to Iraq/Afghanistan War veterans, according to an updated research review in the July Journal of Occupational and Environmental Medicine, official publication of the American College of Occupational and Environmental Medicine (ACOEM).

"Gulf War deployment continues to be strongly associated with increased MSI, affecting a considerable proportion of Gulf War veterans," write Stella M. Gwini and colleagues of Monash University, Melbourne, Australia. Multisymptom illness refers to chronic, unexplained symptoms affecting several body systems, such as fatigue, mood or cognitive (thinking) problems, and joint and muscle pain.

The researchers analyzed data from seven previous studies evaluating the prevalence of MSI among veterans of the 1990-1991 Gulf War as well as the Afghanistan and Iraq Wars. In addition to including some more recent, higher-quality studies, the review added an Australian study to previous data from the United States and the United Kingdom.

Although estimates varied widely, MSI prevalence was substantially higher in Gulf War veterans: 26 to 65 percent compared with 12 to 37 percent in Iraq/Afghanistan War veterans. On pooled data analysis, the odds of MSI were 2.5 times higher in Gulf War veterans versus other military groups.

The odds were slightly lower in higher-quality studies. Veterans who were deployed to Iraq or Afghanistan were more likely to have MSI than non-deployed personnel — but their risk was still not as high as in deployed Gulf War veterans.

The study provides "updated and more robust estimates" of the risk of MSI in Gulf War veterans, compared to other military personnel. Ms. Gwini and coauthors conclude that their results "highlight the continuing problem and magnitude of MSI in Gulf War veterans, calling for ongoing awareness of the need for timely health assessments and health care."

Citation — Gwini SM, Forbes AB, Sim MR, Kelsall HL. Multisymptom illness in Gulf War veterans: a systematic review and meta-analysis. J Occup Environ Med. 2016;58(7):659-67.

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