SAN FRANCISCO—Among a cohort of recently deployed soldiers, headaches were frequent but were more severe, frequent, and migrainous if associated with concussion, according to a report presented at the 60th Annual Scientific Meeting of the American Headache Society. At one-year follow-up, headache frequency had decreased in soldiers with posttraumatic headache (PTH) but remained higher in this group than in those whose headaches were presumed to be unrelated to head injury, said Ann I. Scher, PhD, Director and Professor of Preventive Medicine and Biostatistics at the Uniformed Services University of the Health Sciences in Bethesda, Maryland, and colleagues.
“There are limited data on the phenotypic differences between headaches related to mild traumatic brain injury and ‘regular’ headaches,” Dr. Scher said. “A better understanding of the posttraumatic headache phenotype will inform the design of interventional studies for this difficult to treat population.”
Dr. Scher and colleagues designed a study to compare headache features and one-year prognosis in a cohort of recently deployed soldiers with and without a recent history of a deployment-related mild traumatic brain injury (ie, concussion).
In all, 1,567 soldiers were randomly recruited at Fort Bragg, North Carolina, and Fort Carson, Colorado, within a few days of return from Iraq or Afghanistan. Soldiers with mild traumatic brain injury (ie, cases) and controls were identified based on whether they reported sustaining a mild traumatic brain injury during their most recent deployment. Participants completed a detailed self-administered headache questionnaire. Cases who reported having headaches that started or worsened after a head injury were defined as cases with PTH, and all other cases were defined as cases without PTH. Headache and migraine features assessed were unilateral location, photophobia, phonophobia, nausea, exacerbation, pulsatility, visual aura, sensory aura, pain level, frequency, and allodynia. Headaches were assessed again at three months and 12 months.
Soldiers were primarily young men (mean age, 27; 92% male). Most controls (64%) and mild traumatic brain injury cases (80%) reported having headaches in the past year. Among those with headaches, daily or continuous headache was reported by 5% of controls, 7% of cases without PTH, and 24% of cases with PTH. All headache and migraine features were less common in controls than in cases and less common in cases without PTH than in cases with PTH. Finally, cases without PTH and controls had a similar prevalence of most headache and migraine features, with the exceptions of sensory aura and headache frequency.
At three months, mean annualized headache frequency decreased by about 20 days among cases with PTH but remained unchanged in the other groups. Results were similar at 12 months. Baseline visual or sensory aura and pulsatility were positive prognostic factors associated with reduced headache frequency at 12 months. Baseline headache pain was a negative prognostic factor.