Objective To investigate clinical characteristics and treatment patterns in persistent post-traumatic headache attributed to mild traumatic brain injury. Methods A total of 100 individuals with persistent post-traumatic headache attributed to mild traumatic brain injury were enrolled between July 2018 and June 2019. Deep phenotyping was performed using a semi-structured interview while allodynia was assessed using the 12-item Allodynia Symptom Checklist. Results In 100 subjects with persistent post-traumatic headache, the mean headache frequency was 25.4 ± 7.1 days per month. The most common headache phenotype was chronic migraine-like headache (n = 61) followed by combined episodic migraine-like and tension-type-like headache (n = 29) while nine subjects reported “pure” chronic tension-type-like headache. The most frequent trigger factors were stress, lack of sleep, and bright lights. A history of preventive medication use was reported by 63 subjects, of which 79% reported failure of at least one preventive drug, while 19% reported failure of at least four preventive drugs. Cutaneous allodynia was absent in 54% of the subjects, mild in 23%, moderate in 17%, and severe in 6%. Conclusions The headache profile of individuals with persistent post-traumatic headache most often resembled a chronic migraine-like phenotype or a combined episodic migraine-like and tension-type-like headache phenotype. Migraine-specific preventive medications were largely reported to be ineffective. Therefore, there is a pressing need for pathophysiological insights and disease-specific therapies.

Background Post-traumatic headache (PTH) is associated with considerable disability and reduced health-related quality of life. Despite the very high prevalence of PTH, there are no evidence-based guidelines for PTH treatment. Thus, we found it timely to provide a systematic review of the current literature on acute and preventive pharmacological treatment of PTH using PubMed and Embase databases. Findings Included studies involved acute and preventive pharmacological treatment of headache attributed to traumatic injury to the head in adherence to the International Classification of Headache Disorders (ICHD) criteria. Of 1424 potentially relevant articles identified, 63 were retrieved for detailed evaluation and seven studies (one prospective and six retrospective) met the inclusion criteria. None of the seven included studies were randomized clinical trials (RCTs) or used a placebo-controlled study design. Conclusion We found that there is a lack of high-quality evidence-based studies on the pharmacological treatment of PTH. Future studies are highly needed and must emphasize open-label studies with rigorous methodology or RCTs with a placebo-controlled design.

Background Clinical trials have shown that erenumab is effective and well-tolerated for the preventive treatment of chronic migraine. To extend the results from clinical trials, we assessed the real-world efficacy and safety of erenumab in patients with chronic migraine from the outpatient clinic at the Danish Headache Center. Methods A 52-week, single-center, prospective, observation study of erenumab in adults with chronic migraine who are eligible for treatment with monoclonal antibodies against CGRP or its receptor in Denmark. The primary outcome was defined as proportion of patients who achieved ≥ 30% reduction in monthly migraine days (MMDs) from baseline to weeks 9–12. Results A total of 300 adult patients with chronic migraine were enrolled and received at least one dose of erenumab. At baseline, the mean (SD) number of monthly headache days was 23 ± 4.9 and mean number of MMDs was 16.8 ± 6.4. Of 300 enrolled patients, 273 (91.0%) patients completed 12 weeks of treatment, and 119 (39.7%) completed 52 weeks of treatment. The number of patients who achieved ≥ 30% reduction in MMDs from baseline to weeks 9–12 was 195 (71.4%) of 273 patients. Sustained ≥ 30% reduction in MMDs at all assessment periods throughout the 52-week treatment period was achieved by 102 (34%) of 300 patients. Adverse events occurred in 220 (73.3%) out of 300 patients. The most common adverse event was constipation. Treatment discontinuation due to lack of tolerability occurred in 41 (13.7%) patients. Conclusions Among adult patients with chronic migraine and previous failure of medications for migraine prevention, erenumab was found to be effective and well-tolerated.

Background: Calcitonin gene-related peptide (CGRP) has recently been implicated in the pathogenesis of posttraumatic headache (PTH), which raises the prospect for therapeutic use of monoclonal antibodies targeting CGRP or its receptor. Therefore, we decided to assess the efficacy, tolerability, and safety of erenumab for prevention of persistent PTH attributed to mild traumatic brain injury. Methods: A single-center, non-randomized, single-arm, open-label study of erenumab for adults aged 18-65 years with persistent PTH. Patients were assigned to receive 140-mg erenumab monthly by two subcutaneous 1-mL injections, given every 4 weeks for 12 weeks. The primary outcome measure was the mean change in number of monthly headache days of moderate to severe intensity from baseline (4-week pretreatment period) to week 9 through 12. Tolerability and safety endpoints were adverse events (i.e. number and type). Results: Eighty-nine of 100 patients completed the open-label trial. At baseline, the mean monthly number of headache days of moderate to severe intensity was 15.7. By week 9 through 12, the number was reduced by 2.8 days. The most common adverse events were constipation (n = 30) and injection-site reactions (n = 15). Of 100 patients who received at least one dose of erenumab, two patients discontinued the treatment regimen due to adverse events.

Objective: To demonstrate that calcitonin gene-related peptide (CGRP) induces headache exacerbation with migraine-like features in patients with persistent post-traumatic headache (PTH) attributed to mild traumatic brain injury (TBI). Methods: A randomized, double-blind, placebo-controlled, two-way crossover study was conducted. Analyses were intention-to-treat. Eligible patients were aged 18 to 65 years and had a history of persistent PTH after mild TBI for at least 12 months. Patients were randomized to receive an intravenous infusion of 1.5μg/min of CGRP or placebo (isotonic saline) over 20 minutes on two separate experimental days. A 12-hour observational period was used to evaluate the following outcomes: (1) difference in incidence of headache exacerbation with migraine-like features and (2) difference in area under the curve for headache intensity scores. Results: Thirty patients (mean age = 37 years, 25 women [83%]) were randomized and completed the study. During the 12-hour observational period, 21 of 30 patients (70%) developed headache exacerbation with migraine-like features after CGRP, compared with 6 patients (20%) after placebo (p < 0.001). The baseline-corrected area under the curve for headache intensity scores was significantly larger after CGRP, compared with placebo (p < 0.001). Interpretation: Patients with persistent PTH are hypersensitive to CGRP, which underscores its pathophysiological importance. Furthermore, CGRP-targeted therapies might provide a novel mechanism-based treatment option for patients with persistent PTH.

Objective.-To systematically identify risk factors for the development of post-traumatic headache (PTH) attributed to traumatic brain injury (TBI) as defined in the International Classification of Headache Disorders (ICHD). Background.-PTH is a common sequela of TBI and a leading cause of injury-related disability worldwide. However, little is known about risk factors for the development of PTH attributed to TBI. Methods.-We searched PubMed and Embase for literature on risk factors for the development of acute and/or persistent PTH attributed to TBI in accordance with any version of the ICHD. Original studies published in English and of prospective, cross-sectional or retrospective design were considered for the review. Data extraction was performed independently by 2 investigators. Results.-Of 1993 potentially relevant articles identified, 3 articles met the inclusion criteria. The following risk factors were assessed for the development of acute PTH: age, sex, type of injury, loss of consciousness, previous TBIs, history of primary headache disorders, history of chronic pain condition other than headache, current treatment for depression/anxiety, attention or learning disorders, body mass index, and other diseases (not further specified). None of the included studies assessed risk factors for the development of persistent PTH. Conclusions.-We found that there is little evidence for any risk factors involved in the development of acute PTH, whereas no study had assessed risk factors for the development of persistent PTH. Further studies are warranted and should be powered to examine possible risk factors for the development of PTH. Rigorous methodology and standardized monitoring should be prioritized to support high-quality research and validate potential findings.

We identified 23 articles. Nine studies reported on endothelin-1 plasma concentrations in patients with migraine, eight studies investigated relevant genetic associations, five studies investigated endothelin-1 and spreading depression in animals, and one randomized controlled clinical trial tested the efficacy of an endothelin antagonist in the acute treatment of migraine in patients both with and without aura. Elevated endothelin-1 plasma levels have been reported in the early phase of migraine attacks. Genetic abnormalities related to the endothelin type A receptor have been reported in migraineurs. Endothelin-1 potently induces spreading depression in animals, which may explain the connection between endothelial irritation and migraine aura. Endothelin-1 could be a primary factor in the attack-triggering cascade of migraine attacks with and without aura. Additional studies in humans and animal models are needed to further elucidate the role of endothelin-1 in migraine.

Objective To investigate the association of psychiatric and cognitive comorbidities with persistent post-traumatic headache (PTH) attributed to mild traumatic brain injury (TBI). Methods A total of 100 patients with persistent PTH attributed to mild TBI and 100 age- and gender-matched healthy controls free of mild TBI were enrolled between July 2018 and June 2019. Quality of sleep was evaluated using the Pittsburgh Sleep Quality Index, while symptoms of anxiety and depression were assessed using the Hospital Anxiety and Depression Scale. Cognitive impairment was evaluated using the Montreal Cognitive Assessment questionnaire, while post-traumatic stress disorder (PTSD) was assessed using the Harvard Trauma Questionnaire. Results In 100 patients with persistent PTH, 85% reported poor quality sleep, compared with 42% of healthy controls (P < 0.01). The relative frequency of probable to high risk of anxiety was 52% in the persistent PTH group vs. 8% in healthy controls (P < 0.01), while the relative frequency of probable to high risk of depression was 42% in the persistent PTH group vs. 2% in healthy controls (P < 0.01). Furthermore, 27% of the patients with persistent PTH had mild cognitive impairment while 10% had probable PTSD. Conclusions Poor quality of sleep as well as symptoms suggestive of anxiety and depression were more common in patients with persistent PTH than healthy controls. Clinicians should screen patients with persistent PTH for these comorbidities and develop treatment plans that account for their presence.