title: Prediction of headache severity (density and functional impact) after traumatic brain injury: A longitudinal multicenter study.
abstract: BACKGROUND
  Headache (HA) following traumatic brain injury (TBI) is common, but predictors and time course are not well established, particularly after moderate to severe TBI.
  
  
  METHODS
  A prospective, longitudinal cohort study of HA severity post-TBI was conducted on 450 participants at seven participating rehabilitation centers. Generalized linear mixed-effects models (GLMMs) were used to model repeated measures (months 3, 6, and 12 post-TBI) of two outcomes: HA density (a composite of frequency, duration, and intensity) and HA disruptions to activities of daily living (ADL).
  
  
  RESULTS
  Although HA density and ADL disruptions were nominally highest during the first three months post-TBI, neither showed significant changes over time. At all time points, history of pre-injury migraine was by far the strongest predictor of both HA density and ADL disruptions (odds ratio (OR) = 8.0 and OR = 7.2, averaged across time points, respectively). Furthermore, pre-injury non-migraine HA (at three and six months post-TBI), penetrating-type TBI (at six months post-TBI), and female sex (at six and 12 months post-TBI) were each associated with an increase in the odds of a more severe HA density. Severity of TBI (post-traumatic amnesia (PTA) duration) was not associated with either outcome.
  
  
  CONCLUSIONS
  Individuals with HA at three months after moderate-severe TBI do not improve over the ensuing nine months with respect to HA density or ADL disruptions. Those with pre-injury HA, particularly of migraine type, are at greatest risk for HA post-TBI. Other independent risk factors are penetrating-type TBI and, to a lesser degree and post-acutely only, female sex. Individuals with these risk factors should be monitored and considered for aggressive early intervention.
authors.affiliation: Department of Physical Medicine and Rehabilitation, Virginia Commonwealth University, VA 23298, USA. wwalker@mcvh-vcu.edu
authors.forename: William C
authors.initials: WC
authors.lastname: Walker
authors.forename: Jennifer H
authors.initials: JH
authors.lastname: Marwitz
authors.forename: Amber R
authors.initials: AR
authors.lastname: Wilk
authors.forename: Jessica M
authors.initials: JM
authors.lastname: Ketchum
authors.forename: Jeanne M
authors.initials: JM
authors.lastname: Hoffman
authors.forename: Allen W
authors.initials: AW
authors.lastname: Brown
authors.forename: Sylvia
authors.initials: S
authors.lastname: Lucas
mesh_terms: D000203:Activities of Daily Living; D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001930:Brain Injuries / Q000150:complications*; D015897:Comorbidity; D005260:Female; D006801:Humans; D008137:Longitudinal Studies; D008297:Male; D008875:Middle Aged; D008881:Migraine Disorders / Q000453:epidemiology; D051298:Post-Traumatic Headache / Q000453:epidemiology* / Q000209:etiology*; D055815:Young Adult
keywords: Headache; head injury; outcomes; post-traumatic headache; traumatic brain injury