To examine the association between remote deployment-related Traumatic Brain Injury (TBI) severity, TBI frequency, and other injury characteristics on headache outcome in veterans evaluated for TBI at a local Veterans Administration (VA) polytrauma support clinic.

TBI is the “signature injury” among combat veterans. The extent to which TBI characteristics affect post traumatic headache (PTH) is unknown. Further investigation is needed to elucidate the factors associated with different TBI outcomes.

We conducted a retrospective chart review of 594 comprehensive TBI evaluations between 2011-2021. TBI severity groups were classified as sub-concussive exposure (n = 189), mild TBI (n = 377), moderate TBI (n = 28), and severe TBI (n = 0) based upon Department of Defense/VA severity standards. Adjusted odds ratios, unstandardized β, and 95% Confidence Intervals were estimated for headache prevalence (logistic), headache severity (linear), and prevalence of migraine-like features (logistic) using multivariate regression models adjusted for demographic factors and comorbid mental health diagnoses.

Veterans with a history of moderate TBI had poorer headache outcomes compared to those with a history of mild TBI or sub-concussive exposure. A history of multiple mild TBI was associated with greater headache severity and higher odds of migraine-like features. Mortar-induced mild TBI had greater headache severity, while fall-related TBI had lower headache severity. Alterations of consciousness (AOC) and post-traumatic amnesia (PTA) duration longer than 30 minutes were associated with greater headache severity and higher odds of migraine-like features. Significant protective factors against poor headache outcomes were earlier care and helmet use.

A history of multiple mild TBI and longer duration of AOC and PTA are unique risk factors for poor headache outcome in veterans. Our data support the notion for a dose-response relationship between TBI severity and headache outcome. Past TBI characteristics should be considered when developing headache management plans for veterans.