Cholinergic Autonomic Dysfunction in Veterans With Gulf War Illness: Confirmation in a Population-Based Sample

Background The authors of prior small studies raised the hypothesis that symptoms in veterans of the 1991 Gulf War, such as chronic diarrhea, dizziness, fatigue, and sexual dysfunction, are due to cholinergic autonomic dysfunction. Objective To perform a confirmatory test of this prestated hypothesis in a larger, representative sample of Gulf War veterans. Design Nested case-control study. Setting Clinical and Translational Research Center, University of Texas Southwestern Medical Center, Dallas. Participants Representative samples of Gulf War veterans meeting a validated case definition of Gulf War illness with 3 variants (called syndromes 1-3) and a control group, all selected randomly from the US Military Health Survey. Main Outcome Measures Validated domain scales from the Autonomic Symptom Profile questionnaire, the Composite Autonomic Severity Score, and high-frequency heart rate variability from a 24-hour electrocardiogram. Results The Autonomic Symptom Profile scales were significantly elevated in all 3 syndrome groups (P  Conclusion Autonomic symptoms are associated with objective, predominantly cholinergic autonomic deficits in the population of Gulf War veterans.