When Iraq invaded Kuwait in 1990, a coalition of thirty-nine countries responded. A total of 382 American troops died. Those who survived deployments to the 1990–1991 Gulf War theater of operations and returned to the United States may have been safe from combat, but they were not “safe and sound.” Thirtyseven percent of them were suffering from a strange constellation of symptoms not seen in other locations or after previous wars. Around 250,000 individuals reported developing a chronic multisystem illness that was medically unexplained and persisted for years with little improvement.
They reported symptoms including fatigue, headache, memory problems, muscle/joint pain, diarrhea, dyspepsia/ indigestion, neurological problems, skin conditions, respiratory problems, and more. Previously known as Gulf War Syndrome, Gulf War Illness (GWI) cases have been difficult to classify. Two definitions have emerged: the Kansas definition and the CDC definition. The Kansas definition considers six symptom groups: fatigue and sleep problems, pain, neurologic and mood, gastrointestinal, respiratory symptoms, and skin symptoms. To qualify, patients must have symptoms in at least three of these categories that had developed during or after deploying to the Gulf War, and other conditions must be excluded. The CDC definition takes a symptom-category approach with three categories: fatigue, mood-cognition, and musculoskeletal. It requires symptoms in two of the three categories lasting six months or longer, and it includes a determination of severity. The Kansas definition is more specific and may be more appropriate for research settings, while the CDC definition is broader and may be more useful for clinical purposes.