Multi-symptom illnesses, unexplained illness and Gulf War Syndrome.

Explanatory models for the increased prevalence of ill health in Gulf veterans compared to those not deployed to the Gulf War 1990-1991 remain elusive. This article addresses whether multi-symptom reporting in Gulf veterans are types of medically unexplained symptoms and whether the alleged Gulf War Syndrome is best understood as a medically unexplained syndrome. A review of the epidemiological studies, overwhelmingly cross-sectional, describing ill health was conducted including those that used factor analysis to search for underlying or latent clinical constructs. The overwhelming evidence was that symptoms in Gulf veterans were either in keeping with currently defined psychiatric disorders such as depression and anxiety or were medically unexplained. The application of factor analysis methods had varied widely with a risk of over interpretation in some studies and limiting the validity of their findings. We concluded that ill health in Gulf veterans and the alleged Gulf War Syndrome is best understood within the medically unexplained symptoms and syndromes constructs. The cause of increased reporting in Gulf veterans are still not clear and requires further inquiry into the interaction between sociological factors and symptomatic distress.