Headache among combat-exposed veterans and service members and its relation to mild traumatic brain injury history and other factors: a LIMBIC-CENC study

William C Walker; Sarah W Clark; Kaleb Eppich; Elisabeth A Wilde; Aaron M Martin; Chelsea M Allen; Melissa M Cortez; Mary Jo Pugh; Samuel R Walton; Kimbra Kenney

doi:10.3389/fneur.2023.1242871

Headache among combat-exposed veterans and service members and its relation to mild traumatic brain injury history and other factors: a LIMBIC-CENC study

Front Neurol. 2023 Sep 20:14:1242871. doi: 10.3389/fneur.2023.1242871. eCollection 2023.

Authors

William C Walker^{1

2}, Sarah W Clark², Kaleb Eppich³, Elisabeth A Wilde^{4

5}, Aaron M Martin^{6

7}, Chelsea M Allen³, Melissa M Cortez⁸, Mary Jo Pugh^{9

10}, Samuel R Walton¹, Kimbra Kenney¹¹

Affiliations

¹ Department of Physical Medicine and Rehabilitation (PM&R), School of Medicine, Virginia Commonwealth University, Richmond, VA, United States.
² Richmond Veterans Affairs (VA) Medical Center, Central Virginia VA Health Care System, Richmond, VA, United States.
³ Division of Epidemiology, Department of Internal Medicine, University of Utah, Salt Lake City, UT, United States.
⁴ George E. Wahlen VA Salt Lake City Healthcare System, Salt Lake City, UT, United States.
⁵ Department of Neurology, Traumatic Brain Injury and Concussion Center, University of Utah, Salt Lake City, UT, United States.
⁶ Mental Health and Behavioral Science Service, James A. Haley Veterans' Hospital, Tampa, FL, United States.
⁷ Department of Psychiatry and Behavioral Neurosciences, University of South Florida, Tampa, FL, United States.
⁸ Department of Neurology, University of Utah, Salt Lake City, UT, United States.
⁹ Informatics, Decision-Enhancement, and Analytic Sciences (IDEAS) Center, Salt Lake City, UT, United States.
¹⁰ Department of Internal Medicine, Division of Epidemiology, Spencer Fox Eccles School of Medicine, University of Utah, Salt Lake City, UT, United States.
¹¹ Department of Neurology, Uniformed Services University of the Health Sciences, Bethesda, MD, United States.

Abstract

Background: Headache (HA) is a common persistent complaint following mild traumatic brain injury (mTBI), but the association with remote mTBI is not well established, and risk factors are understudied.

Objective: Determine the relationship of mTBI history and other factors with HA prevalence and impact among combat-exposed current and former service members (SMs).

Design: Secondary cross-sectional data analysis from the Long-Term Impact of Military-Relevant Brain Injury Consortium-Chronic Effects of Neurotrauma Consortium prospective longitudinal study.

Methods: We examined the association of lifetime mTBI history, demographic, military, medical and psychosocial factors with (1) HA prevalence ("lately, have you experienced headaches?") using logistic regression and (2) HA burden via the Headache Impact Test-6 (HIT-6) using linear regression. Each lifetime mTBI was categorized by mechanism (blast-related or not) and setting (combat deployed or not). Participants with non-credible symptom reporting were excluded, leaving N = 1,685 of whom 81% had positive mTBI histories.

Results: At a median 10 years since last mTBI, mTBI positive participants had higher HA prevalence (69% overall, 78% if 3 or more mTBIs) and greater HA burden (67% substantial/severe impact) than non-TBI controls (46% prevalence, 54% substantial/severe impact). In covariate-adjusted analysis, HA prevalence was higher with greater number of blast-related mTBIs (OR 1.81; 95% CI 1.48, 2.23), non-blast mTBIs while deployed (OR 1.42; 95% CI 1.14, 1.79), or non-blast mTBIs when not deployed (OR 1.23; 95% CI 1.02, 1.49). HA impact was only higher with blast-related mTBIs. Female identity, younger age, PTSD symptoms, and subjective sleep quality showed effects in both prevalence and impact models, with the largest mean HIT-6 elevation for PTSD symptoms. Additionally, combat deployment duration and depression symptoms were factors for HA prevalence, and Black race and Hispanic/Latino ethnicity were factors for HA impact. In sensitivity analyses, time since last mTBI and early HA onset were both non-significant.

Conclusion: The prevalence of HA symptoms among formerly combat-deployed veterans and SMs is higher with more lifetime mTBIs regardless of how remote. Blast-related mTBI raises the risk the most and is uniquely associated with elevated HA burden. Other demographic and potentially modifiable risk factors were identified that may inform clinical care.

Keywords: blast injuries; concussion; headache; military medicine; postconcussive headache; prediction; traumatic brain injury; veterans.

Abstract

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