Background: Previous deployments like that to the Persian Gulf in 1991 produced veterans with post-deployment symptom-based health problems with no medical explanation. This was termed Gulf War illness or medically unexplained illness (MUI). If previous wars are any indication, some soldiers currently deployed to hostile areas also will return home with unexplained symptom-based illnesses. However, when this study began there was virtually no pre-war, prospective data on risk and resilience factors associated with MUI. This study is attempting to fill that gap.

Objectives: Our goals are to: (a) determine pre- and immediate post-deployment factors predicting later MUI and poor functional status, (b) improve previous methodological problems (e.g., selection bias, recall bias and lack of baseline controls) in studies of MUI, and (c) relate pre-deployment risk factors (e.g., personality, stressor reactivity) and resilience factors (e.g., coping style, social support) to post-deployment functional status.

Background: Previous deployments like that to the Persian Gulf in 1991 produced veterans with post-deployment symptom-based health problems with no medical explanation. This was termed Gulf War illness or medically unexplained illness (MUI). If previous wars are any indication, some soldiers currently deployed to hostile areas also will return home with unexplained symptom-based illnesses. However, was virtually no pre-war, prospective data on risk and resilience factors associated with MUI before 2001. This study will attempt to fill that gap. Objectives: Our goals are to: (a) determine pre- and immediate post-deployment factors predicting later MUI and poor functional status, (b) improve previous methodological problems (e.g., selection bias, recall bias and lack of baseline controls) in studies of MUI, and (c) relate pre-deployment risk factors (e.g., personality, stressor reactivity) and resilience factors (e.g., coping style, social support) to post-deployment functional status. Methods: This study uses a prospective, longitudinal observational design to assess risk and resilience factors for post-war MUI in Reserve and National Guard enlisted personnel. A stratified random sample of more than 700 subjects will be drawn from those undergoing pre- and post-mobilization readiness processing at Fort Dix, NJ and Camp Shelby, MS. Personnel will be tested pre-mobilization (Phase 1), immediately after mobilization (Phase 2) and at 3 months and 1 year post-deployment (Phases 3 & 4). Predictor variables include personality, social support, coping style, non-specific symptoms, sympathetic cardiac stress reactivity, and cortisol stress reactivity. Control variables include prior traumatic events, current distress, PTSD symptoms, socially desirable responding, body mass index, deployment experiences, environmental exposures and demographics (e.g., age, gender). Outcome variables include functional status, healthcare utilization, and MUI status (using CDC criteria for chronic multisymptom illness developed after the first Gulf War). Status: Publications and presentations are being prepared. Impact: The larger, prospective study with soldiers will help us to identify pre- and early post-deployment risk and resilience factors important in MUI, functional status, and healthcare utilization. There is an urgent need for both pre- and post-deployment predictors of later MUI uncontaminated by recall bias, and the selection bias of studying only treatment-seekers. If we are to understand how to best treat veterans presenting with unexplained symptoms, then we need to know which pre-war factors are most useful in predicting who is most likely to be resilient and who is most likely to be at risk for later unexplained illness.

Inclusion Criteria:

• Army Reserve and National Guard soldiers deploying to a hazardous deployment from Fort Dix, New Jersey (NJ) and Camp Shelby, Mississippi (MS)

Exclusion Criteria:

• There are some drug exclusions for anything that substantially affects cardiovascular function.

Army National Guard & Reserves Soldiers deploying to either Iraq or Afghanistan. Outcome measures assessed at all 4 time points (pre-deployment, immediately post-deployment, 3 months post-return, 1 year post-return)

All enrolled participants

Data were collected at all 4 time points (pre-deployment=Phase 1, immediate post-deployment=Phase 2, 3 months post-deployment=Phase 3, one year post-deployment=Phase 4). The entire duration was about 2 years given an average deployment of about one year.

The sample was comprised of only Army National Guard and Reserve military personnel, and therefore results may not generalize to the broader population of military personnel from other Service branches or components.