Symptom Factor Analysis, Clinical Findings, and Functional Status in a Population-Based Case Control Study of Gulf WarUnexplained Illness

Abstract

Few epidemiological studies have been conducted that have incorporated clinical evaluations of Gulf War veterans with unexplained health symptoms and healthy controls. We conducted a mail survey of 2022 Gulf War veterans residing in the northwest United States and clinical examinations on a subset of 443 responders who seemed to have unexplained health symptoms or were healthy. Few clinical differences were found between cases and controls. The most frequent unexplained symptoms were cognitive/psychological, but significant overlap existed with musculoskeletal and fatigue symptoms. Over half of the veterans with unexplained musculoskeletal pain met the criteria for fibromyalgia, and a significant portion of the veterans with unexplained fatigue met the criteria for chronic fatigue syndrome. Similarities were found in the clinical interpretation of unexplained illness in this population and statistical factor analysis performed by this study group and others.

Posttraumatic stress disorder, tenderness, and fibromyalgia syndrome: are they different entities?

“…Neumann et al [39] analyzed the characteristics of FMS in men and showed that, compared to women, men reported more severe symptoms, decreased PF, and a lower quality of life. On the other hand, a follow-up study of patients who sustained neck injuries following a motor vehicle accident and developed FMS showed that men were less likely than women to remain fibromyalgic 3 years after the event (11% vs. 100%, respectively) [40].…”

Prior health care utilization as a potential determinant of enrollment in a 21-year prospective study, the Millennium Cohort Study

“…Analysis of individual diagnoses within the broad diagnostic categories of hospitalizations significantly associated with response focused on the five most frequent three-digit diagnostic codes to examine their association with response. Additionally, specific ICD-9-CM diagnoses that have previously been indicative of chronic multisymptom illness were explored [14][15][16][17][18][19][20][21][22][23][24][25]. To further evaluate health care usage differences between responders and nonresponders, the mean number of days spent hospitalized or in outpatient care during the year prior to enrollment was also compared.…”

A status report on chronic fatigue syndrome.

“…Nearly 10% of deployed American troops returned home with a host of medically unexplained symptoms-primarily fatigue, musculoskeletal achiness, and cognitive dysfunction. In a survey of healthcare-seeking GVs, we found that 16.1% reported symptoms consistent with CFS (77) and that, on careful clinical evaluation, many fulfilled the published case definition for CFS (42); finding CFS as a common diagnosis in symptomatic GVs has been reported by others, as well (78). The problem with linking toxic factors with CFS is that veterans did not suffer symptoms of acute exposure to such factors.…”