in only one of the three hospital systems examined. The committee notes that symptoms of unexplained illness may not be severe enough to require hospitalization in many cases.
Chronic pain of unexplained origin is one symptom reported more frequently by deployed than nondeployed Gulf War veterans. A meta-analysis of 20 studies of Gulf War veterans found that deployment was most commonly associated with abdominal pain, but back, joint, and muscle pains were also frequently reported. One study of pain in Australian Vietnam veterans found that somatoform pain disorder, a psychiatric diagnosis, was associated with combat exposure.
PTSD is also associated with increased reporting of symptoms, medical conditions, and poor health in veterans, both male and female. Self-reports of more health problems in veterans with PTSD than in those without PTSD have also been confirmed by physical examination. Although combat exposure is associated with increased symptom reporting, PTSD appears to be an even stronger predictor of reports of poor health.
PTSD is widely associated with self-reports of pain in both civilian and veteran populations. Veterans of World War II, the Vietnam War, the Gulf War, and OIF and OEF who have PTSD all report more chronic pain than veterans without PTSD. The chronic pain is not specific; back pain, headaches (including migraines), and joint pain are all reported frequently by both male and female veterans.
The studies cited above have important limitations. Researchers used different terminology for symptoms, and definitions or descriptions of what was meant by the symptom, such as backache or cough, are lacking. Some asked veterans to indicate how much a symptom bothered them over a specific period; others simply asked for an indication of whether the veterans had ever had the symptom after the war. The onset and duration of the symptom were not always assessed or reported. For the studies of PTSD, the veterans were often not diagnosed but only screened for the disorder. And none of the studies indicated whether the veterans had had any of the symptoms before the war in which they were deployed. All those factors make it difficult to compare symptoms among studies.
The committee concludes that there is limited but suggestive evidence of an association between deployment to a war zone and increased symptom reporting, unexplained illness, and chronic pain.