Targeted dietary interventions to reduce pain in persistent post-traumatic headache among service members: Protocol for a randomized, controlled parallel-group trial.

introductionPost-traumatic headache (PTH) is common after traumatic brain injury (TBI), especially among active-duty service members (SMs), affecting up to 35% of patients with chronic TBI. Persistent PTH is disabling and frequently unresponsive to treatment and is often migrainous. Here, we describe a trial assessing whether dietary modifications to increase n-3 eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) and reduce n-6 linoleic acid (LA), will alter nociceptive lipid mediators and result in clinical improvements in persistent PTH.

methodsThis prospective, randomized, controlled trial tests the efficacy, safety, and biochemical effects of targeted, controlled alterations in dietary n-3 and n-6 fatty acids in 122 adult SMs and military healthcare beneficiaries with diagnosed TBI associated with actively managed persistent frequent (>8 /month) PTH with migraine. Following a 4-week baseline, participants are randomized to one of two equally intensive dietary regimens for 12 additional weeks: 1) increased n-3 EPA + DHA with low n-6 LA (H3L6); 2) usual US dietary content of n-3 and n-6 fatty acids (Control). During the intervention, participants receive diet arm-specific study oils and foods sufficient for 75% of caloric needs and comprehensive dietary counseling. Participants complete daily headache diaries throughout the intervention. Clinical outcomes, including the Headache Impact Test (HIT-6), headache hours per day, circulating blood fatty acid levels, and bioactive metabolites, are measured pre-randomization and at 6 and 12 weeks. Planned primary analyses include pre-post comparisons of treatment groups on clinical measures using ANCOVA and mixed-effects models. Similar approaches to explore biochemical and exploratory clinical outcomes are planned. CLINICALTRIALS: gov registration: NCT03272399.