A population-based investigation into the prevalence of chronic fatigue syndrome in United States military Veterans with chronic pain

ABSTRACT

Objective

Chronic fatigue syndrome (CFS) is a debilitating illness characterized by persistent fatigue among other symptoms. Pain symptoms are common and included in the diagnostic criteria for CFS but are not required for diagnosis. Despite the association between CFS and pain, few studies have examined CFS in the context of chronic pain (CP) conditions. The current study estimates the period prevalence of comorbid CFS among military Veterans with CP and compares sociodemographic characteristics and CP conditions of Veterans with CP + CFS to those with CP without CFS.

Methods

This study included Veterans Health Administration (VHA) data on 2,261,030 patients with chronic pain in 2018. Sociodemographic characteristics included age, sex, race, ethnicity, and rurality. Descriptive statistics were used to describe the sample and between-group comparisons included independent samples t-tests and chi-square tests of independence. Effect sizes were also examined.

Results

A total of 15,248 (0.67%) of Veterans with CP also had a diagnosis of CFS. Veterans diagnosed with CP + CFS were younger and were more likely to be female, White, non-Hispanic, and rural-dwelling. However, small and weak effect sizes were observed for these differences. The majority of Veterans with CP + CFS had limb/extremity (69.20%) back pain (53.44%), or abdominal/bowel pain (24.11%).

Conclusion

As CDC treatment recommendations for CFS include treating pain first, studying CFS in the context of CP is critically important. Veterans diagnosed with CP + CFS appear demographically similar, compared to Veterans with CP without CFS. Examining the utilization of pain-related healthcare services among this group would be a useful next step.

KEYWORDS:

• Chronic fatigue syndrome
• chronic pain
• military Veterans
• comorbidity
• prevalence

Acknowledgements

Many thanks to Dr. Molly Nikolas and Dr. Natalie Denburg for the helpful feedback on this manuscript.

Disclosure statement

No potential conflict of interest was reported by the author(s).

Additional information

Funding

This work was funded in part by the U.S. Department of Veterans Affairs , Office of Rural Health (Project #03609), by the U.S. Department of Veterans Affairs, HSR&D through CADRE (Project #CIN 13-412), and by the University of Iowa Ballard & Seashore Dissertation Fellowship (JLA, Spring 2023). The views expressed in this paper are those of the authors and do not necessarily reflect the position or policy of the U.S. Department of Veterans Affairs or the U.S. Government.

Notes on contributors

Jenna L. Adamowicz

Jenna L. Adamowicz is a graduate student in the Clinical Science program at the University of Iowa and a doctoral intern at VA Connecticut.

Emily B. K. Thomas

Emily B. K. Thomas is a Clinical Assistant Professor in the Department of Psychological and Brain Sciences at the University of Iowa.

Brian C. Lund

Brian C. Lund is a Core Investigator with CADRE at the Iowa City VA.

Mary A. Driscoll

Mary A. Driscoll is a Clinical Research Psychologist with PRIME at VA Connecticut and an Assistant Professor of Psychiatry at Yale School of Medicine.

Mark Vander Weg

Mark Vander Weg is Professor and Head of the Department of Community and Behavioral Health, with secondary appointments in the Departments of Internal Medicine and Psychological and Brain Sciences at the University of Iowa.

Katherine Hadlandsmyth

Katherine Hadlandsmyth is an Investigator with CADRE and VRHRC at the Iowa City VA and an Associate Professor of Anesthesia and Psychiatry and Psychology at the University of Iowa.