Different clinical phenotypes of persistent post-traumatic headache exhibit distinct sensory profiles

Biological markers of brain network connectivity and pain sensitivity distinguish low coping from high coping Veterans with persistent post-traumatic headache

Headache is the most common type of pain following mild traumatic brain injury. Roughly half of those with persistent post-traumatic headache (PPTH) also report neck pain which is associated with greater severity and functional impact of headache. This observational cohort study aimed to identify biological phenotypes to help inform mechanism-based approaches in the management of PPTH with and without concomitant neck pain. Thirty-three military Veterans (mean (SD) = 37±16 years, 29 males) with PPTH completed a clinical assessment, quantitative sensory testing, and magnetic resonance imaging of the brain and cervical spine. Multidimensional phenotyping was performed using a Random Forest analysis and Partitioning Around Medoids (PAM) clustering of input features from three biologic domains: 1) resting state functional connectivity (rsFC) of the periaqueductal gray (PAG), 2) quality and size of cervical muscles, and 3) mechanical pain sensitivity and central modulation of pain. Two subgroups were distinguished by biological features that included forehead pressure pain threshold and rsFC between the PAG and selected nodes within the default mode, salience, and sensorimotor networks. Compared to the High Pain Coping group, the Low Pain Coping group exhibited higher pain-related anxiety (p=0.009), higher pain catastrophizing (p=0.004), lower pain self-efficacy (p=0.010), and greater headache-related disability (p=0.012). Findings suggest that greater functional connectivity of pain modulation networks involving the PAG combined with impairments in craniofacial pain sensitivity, but not cervical muscle health, distinguish a clinically important subgroup of individuals with PPTH who are less able to cope with pain and more severely impacted by headache.

Posttraumatic headache: pain related evoked potentials (PREP) and conditioned pain modulation (CPM) to assess the pain modulatory function

Posttraumatic headache (PTH) is common following traumatic brain injury and impacts quality of life. We investigated descending pain modulation as one possible mechanism for PTH and correlated it to clinical measures. Pain-related evoked potentials (PREP) were recorded in 26 PTH-patients and 20 controls after electrical stimulation at the right hand and forehead with concentric surface electrodes. Conditioned pain modulation (CPM) was assessed using painful cutaneous electric stimulation (PCES) on the right hand as test stimulus and immersion of the left hand into 10 °C-cold water bath as conditioning stimulus based on changes in pain intensity and in amplitudes of PCES-evoked potentials. All participants completed questionnaires assessing depression, anxiety, and pain catastrophising. PTH-patients reported significantly higher pain ratings during PREP-recording in both areas despite similar stimulus intensity at pain threshold. N1P1-amplitudes during PREP and CPM-assessment were lower in patients in both areas, but statistically significant only on the hand. Both, PREP-N1-latencies and CPM-effects (based on the N1P1-amplitudes and pain ratings) were similar in both groups. Patients showed significantly higher ratings for anxiety and depression, which did not correlate with the CPM-effect. Our results indicate generalized hyperalgesia for electrical stimuli in both hand and face in PTH. The lacking correlation between pain ratings and EEG parameters indicates different mechanisms of pain perception and nociception.

Sensory hypersensitivities are associated with post-traumatic headache-related disability

OBJECTIVE

To examine whether sensory hypersensitivity contributes to headache-related disability in a secondary analysis of patients with post-traumatic headache.

BACKGROUND

Up to one-third of individuals with traumatic brain injuries report persistent headache 3 months post-injury. High rates of allodynia and photophobia have been observed in clinical studies and animal models of post-traumatic headache, but we do not fully understand how sensory amplifications impact post-traumatic headache-related disability.

METHODS

We identified a cross-sectional sample of patients from the American Registry for Migraine Research database with new or worsening headaches post-head injury from 2016 to 2020 and performed a secondary analysis of those data. We modeled the relationship between sensory sensitivity and Migraine Disability Assessment scores using questionnaires. Candidate variables included data collection features (study site and year), headache-related and general clinical features (headache frequency, migraine diagnosis, abuse history, sex, age, cognitive and affective symptom scores), and sensory symptoms (related to light, sound, and touch sensitivity).

RESULTS

The final sample included 193 patients (median age 46, IQR 22; 161/193, 83.4% female). Migraine Disability Assessment scores ranged from 0 to 260 (median 47, IQR 87). The final model included allodynia, hyperacusis, photosensitivity, headache days per month, abuse history, anxiety and depression, cognitive dysfunction, and age (R2  = 0.43). An increase of one point in allodynia score corresponded to a 3% increase in headache disability (95% CI: 0%-7%; p = 0.027), an increase of one-tenth of a point in the photosensitivity score corresponded to a 12% increase (95% CI: 3%-25%; p = 0.002), and an increase of one point in the hyperacusis score corresponded to a 2% increase (95% CI: 0%-4%; p = 0.016).

CONCLUSIONS

Increased photosensitivity, allodynia, and hyperacusis were associated with increased headache-related disability in this sample of patients with post-traumatic headache. Symptoms of sensory amplification likely contribute to post-traumatic headache-related disability and merit an ongoing investigation into their potential as disease markers and treatment targets.

Post-Traumatic Headache: A Review of Prevalence, Clinical Features, Risk Factors, and Treatment Strategies

Post-traumatic headache (PTH) is a common and debilitating consequence of mild traumatic brain injury (mTBI) that can occur over one year after the head impact event. Thus, better understanding of the underlying pathophysiology and risk factors could facilitate early identification and management of PTH. There are several factors that could influence the reporting of PTH prevalence, including the definition of concussion and PTH. The main risk factors for PTHs include a history of migraines or headaches, female gender, younger age, greater severity of the head injury, and co-occurring psychological symptoms, such as anxiety and depression. PTH clinical profiles vary based on onset, duration, and severity: tension-type headache, migraine headaches, cervicogenic headache, occipital neuralgia, and new daily persistent headache. Pharmacological treatments often consist of analgesics and non-steroidal anti-inflammatory drugs, tricyclic antidepressants, or antiepileptic medication. Cognitive behavioral therapy, relaxation techniques, biofeedback, and physical therapy could also be used for PTH treatment. Our work highlighted the need for more rigorous studies to better describe the importance of identifying risk factors and patient-centered treatments and to evaluate the effectiveness of the existing treatment options. Clinicians should consider a multidisciplinary approach to managing PTH, including pharmacotherapy, cognitive behavioral therapy, and lifestyle changes.

Total tenderness score and pressure pain thresholds in persistent post-traumatic headache attributed to mild traumatic brain injury

Objective

To investigate whether persistent post-traumatic headache attributed to mild traumatic brain injury (TBI) is associated with more pronounced pericranial tenderness and lower pressure pain thresholds (PPTs) in the head and neck region, compared with healthy controls.

Methods

Patients with persistent post-traumatic headache (n = 100) and age- and gender-matched healthy controls (n = 100) were included between July 2018 and June 2019. Total tenderness score (TTS) was used to assess pericranial tenderness by bilateral manual palpation in eight muscles or tendon insertions. Summation was then used to calculate a TTS from 0 to 48 based on individual right- and left-sided scores; higher TTS score indicated more pronounced pericranial tenderness. PPTs were examined in m. temporalis and m. trapezius (upper and middle part) using an electronic pressure algometer that applies increasing blunt pressure at a constant rate.

Results

The TTS score was higher in patients with persistent post-traumatic headache (median, 21; IQR, 12–31), compared with healthy controls (median, 10; IQR, 6–17; P < .001). PPTs were lower in patients with persistent post-traumatic headache than in controls in both the left-sided m. temporalis (mean ± SD, 157.5 ± 59.9 vs. 201.1 ± 65.2; P < .001) and right-sided m. temporalis (mean ± SD, 159.5 ± 63.8 vs. 212.3 ± 61.9; P < .001). Furthermore, patients with persistent post-traumatic headache also had lower left- and right-sided PPTs in the upper as well as middle part of m. trapezius, compared with healthy controls; all P values were .05 or less.

Conclusions

Among patients with persistent post-traumatic headache, pericranial tenderness was more pronounced and PPTs in the head and neck region were lower than in healthy controls free of headache and mild TBI. Further research is needed to better understand the involvement of pericranial myofascial nociceptors in the disease mechanisms underlying post-traumatic headache.

Supplementary Information

The online version contains supplementary material available at 10.1186/s10194-022-01457-1.

DTI and MTR Measures of Nerve Fiber Integrity in Pediatric Patients With Ankle Injury

Acute peripheral nerve injury can lead to chronic neuropathic pain. Having a standardized, non-invasive method to evaluate pathological changes in a nerve following nerve injury would help with diagnostic and therapeutic assessments or interventions. The accurate evaluation of nerve fiber integrity after injury may provide insight into the extent of pathology and a patient's level of self-reported pain. The aim of this investigation was to evaluate the extent to which peripheral nerve integrity could be evaluated in an acute ankle injury cohort and how markers of nerve fiber integrity correlate with self-reported pain levels in afferent nerves. We recruited 39 pediatric participants with clinically defined neuropathic pain within 3 months of an ankle injury and 16 healthy controls. Participants underwent peripheral nerve MRI using diffusion tensor (DTI) and magnetization transfer imaging (MTI) of their injured and non-injured ankles. The imaging window was focused on the branching point of the sciatic nerve into the tibial and fibular division. Each participant completed the Pain Detection Questionnaire (PDQ). Findings demonstrated group differences in DTI and MTI in the sciatic, tibial and fibular nerve in the injured ankle relative to healthy control and contralateral non-injured nerve fibers. Only AD and RD from the injured fibular nerve correlated with PDQ scores which coincides with the inversion-dominant nature of this particular ankle injuruy cohort. Exploratory analyses highlight the potential remodeling stages of nerve injury from neuropathic pain. Future research should emphasize sub-acute time frames of injury to capture post-injury inflammation and nerve fiber recovery.

Somatosensory dysfunction in patients with posttraumatic headache: A systematic review

OBJECTIVES

Aim of the review is to summarize the knowledge about the sensory function and pain modulatory systems in posttraumatic headache and discuss its possible role in patients with posttraumatic headache.

BACKGROUND

Posttraumatic headache is the most common complication after traumatic brain injury, and significantly impacts patients' quality of life. Even though it has a high prevalence, its origin and pathophysiology are poorly understood. Thereby, the existing treatment options are insufficient. Identifying its mechanisms can be an important step forward to develop target-based personalized treatment.

METHODS

We searched the PubMed database for studies examining pain modulation and/or quantitative sensory testing in individuals with headache after brain injury.

RESULTS

The studies showed heterogenous alterations in sensory profiles (especially in heat and pressure pain perception) compared to healthy controls and headache-free traumatic brain injury-patients. Furthermore, pain inhibition capacity was found to be diminished in subjects with posttraumatic headache.

CONCLUSIONS

Due to the small number of heterogenous studies a distinct sensory pattern for patients with posttraumatic headache could not be identified. Further research is needed to clarify the underlying mechanisms and biomarkers for prediction of development and persistence of posttraumatic headache.

Mild traumatic brain injury affects the features of migraine

BACKGROUND

Headache is one of the most common symptoms after concussion, and mild traumatic brain injury (mTBI) is a risk factor for chronic migraine (CM). However, there remains a paucity of data regarding the impact of mTBI on migraine-related symptoms and clinical course.

METHODS

Of 2161 migraine patients who participated in the American Registry for Migraine Research between February 2016 and March 2020, 1098 completed questions assessing history of TBI (50.8%). Forty-four patients reported a history of moderate to severe TBI, 413 patients reported a history of mTBI. Patients' demographics, headache symptoms and triggers, history of physical abuse, allodynia symptoms (ASC-12), migraine disability (MIDAS), depression (PHQ-2), and anxiety (GAD-7) were compared between migraine groups with (n = 413) and without (n = 641) a history of mTBI. Either the chi-square-test or Fisher's exact test, as appropriate, was used for the analyses of categorical variables. The Mann-Whitney test was used for the analyses of continuous variables. Logistic regression models were used to compare variables of interest while adjusting for age, gender, and CM.

RESULTS

A significantly higher proportion of patients with mTBI had CM (74.3% [307/413] vs. 65.8% [422/641], P = 0.004), had never been married or were divorced (36.6% [147/402] vs. 29.4% [187/636], P = 0.007), self-reported a history of physical abuse (24.3% [84/345] vs. 14.3% [70/491], P <  0.001), had mild to severe anxiety (50.5% [205/406] vs. 41.0% [258/630], P = 0.003), had headache-related vertigo (23.0% [95/413] vs. 15.9% [102/640], P = 0.009), and difficulty finding words (43.0% [174/405] vs. 32.9% [208/633], P <  0.001) in more than half their attacks, and headaches triggered by lack of sleep (39.4% [155/393] vs. 32.6% [198/607], P = 0.018) and reading (6.6% [26/393] vs. 3.0% [18/607], P = 0.016), compared to patients without mTBI. Patients with mTBI had significantly greater ASC-12 scores (median [interquartile range]; 5 [1-9] vs. 4 [1-7], P < 0.001), MIDAS scores (42 [18-85] vs. 34.5 [15-72], P = 0.034), and PHQ-2 scores (1 [0-2] vs. 1 [0-2], P = 0.012).

CONCLUSION

Patients with a history of mTBI are more likely to have a self-reported a history of physical abuse, vertigo, and allodynia during headache attacks, headaches triggered by lack of sleep and reading, greater headache burden and headache disability, and symptoms of anxiety and depression. This study suggests that a history of mTBI is associated with the phenotype, burden, clinical course, and associated comorbid diseases in patients with migraine, and highlights the importance of inquiring about a lifetime history of mTBI in patients being evaluated for migraine.

Different forms of traumatic brain injuries cause different tactile hypersensitivity profiles

ABSTRACT

Chronic complications of traumatic brain injury represent one of the greatest financial burdens and sources of suffering in the society today. A substantial number of these patients suffer from posttraumatic headache (PTH), which is typically associated with tactile allodynia. Unfortunately, this phenomenon has been understudied, in large part because of the lack of well-characterized laboratory animal models. We have addressed this gap in the field by characterizing the tactile sensory profile of 2 nonpenetrating models of PTH. We show that multimodal traumatic brain injury, administered by a jet-flow overpressure chamber that delivers a severe compressive impulse accompanied by a variable shock front and acceleration-deceleration insult, produces long-term tactile hypersensitivity and widespread sensitization. These are phenotypes reminiscent of PTH in patients, in both cephalic and extracephalic regions. By contrast, closed head injury induces only transient cephalic tactile hypersensitivity, with no extracephalic consequences. Both models show a more severe phenotype with repetitive daily injury for 3 days, compared with either 1 or 3 successive injuries in a single day, providing new insight into patterns of injury that may place patients at a greater risk of developing PTH. After recovery from transient cephalic tactile hypersensitivity, mice subjected to closed head injury demonstrate persistent hypersensitivity to established migraine triggers, including calcitonin gene-related peptide and sodium nitroprusside, a nitric oxide donor. Our results offer the field new tools for studying PTH and preclinical support for a pathophysiologic role of calcitonin gene-related peptide in this condition.

Photophobia and allodynia in persistent post-traumatic headache are associated with higher disease burden

OBJECTIVE

To assess photophobia and allodynia in subjects with post-traumatic headache and examine how these sensory hypersensitivities associate with clinical measures of disease burden.

BACKGROUND

Post-traumatic headache is the most frequent and disabling long-term consequence of mild traumatic brain injury. There is evidence of sensory dysfunction in acute post-traumatic headache, and it is known from other headache conditions that sensory amplifications correlate with more severe disease. However, systematic studies in post-traumatic headache are surprisingly scarce.

METHODS

We tested light and tactile sensitivity, along with measures of disease burden, in 30 persistent post-traumatic headache subjects and 35 controls.

RESULTS

In all, 79% of post-traumatic headache subjects exhibited sensory hypersensitivity based on psychophysical assessment. Of those exhibiting hypersensitivity, 54% exhibited both light and tactile sensitivity. Finally, sensory thresholds were correlated across modalities, as well as with headache attack frequency.

CONCLUSIONS

In this study, post-traumatic headache subjects with both light and tactile sensitivity had significantly higher headache frequencies and lower sensitivity thresholds to both modalities, compared to those with single or no sensory hypersensitivity. This pattern suggests that hypersensitivity across multiple modalities may be functionally synergistic, reflect a higher disease burden, and may serve as candidate markers of disease.

Sensory hypersensitivities in those with persistent post-traumatic headache versus migraine

Background and Objective:

Symptoms of persistent post-traumatic headache (PPTH) most often resemble those of migraine, including the presence of photo-, phono-, and cutaneous hypersensitivities. The severity of these hypersensitivity symptoms in those with PPTH compared to those with migraine has yet to be fully elucidated. The objective of this study was to compare symptoms of sensory hypersensitivities between PPTH, migraine, and healthy controls (HCs). Further defining characteristics of PPTH and its similarities to migraine might assist with developing future diagnostic criteria for PPTH and provide insights into PPTH mechanisms.

Methods:

This analysis included 56 individuals with PPTH attributed to mild traumatic brain injury, 30 with migraine, and 36 HCs. To assess sensory hypersensitivities, all subjects completed the Allodynia Symptom Checklist-12, the Photosensitivity Assessment Questionnaire, and the Hyperacusis Questionnaire. Differences among groups were assessed using Fisher’s exact test, Kruskal–Wallis, or Mann–Whitney U test.

Results:

PPTH and migraine groups had greater severity of cutaneous, photo-, and phono-hypersensitivity symptoms compared to HCs. There were no statistically significant differences between the PPTH and migraine groups for cutaneous allodynia (median [first quartile, third quartile]; PPTH: 4.0 [2.0, 7.0]; migraine: 5.0 [3.0, 8.0]; p = 0.54) or photosensitivity severity (PPTH: 5.0 [2.0, 7.0]; migraine: 5.0 [2.0, 6.0]; p = 0.53). Those with PPTH had higher hyperacusis scores compared to those with migraine (PPTH: 23.0 [17.0, 31.0]; migraine: 13.5 [9.0, 24.0]; p = 0.001).

Conclusion:

Sensory hypersensitivity symptoms among individuals with PPTH are at least as severe as those experienced by people with migraine. Results further confirm symptom similarities between PPTH and migraine and could suggest that PPTH and migraine have a partially shared underlying pathophysiology.

Persistent post-traumatic headache: a migrainous loop or not? The preclinical evidence

Background

According to the International Classification of Headache Disorders 3, post-traumatic headache (PTH) attributed to traumatic brain injury (TBI) is a secondary headache reported to have developed within 7 days from head injury, regaining consciousness following the head injury, or discontinuation of medication(s) impairing the ability to sense or report headache following the head injury. It is one of the most common secondary headache disorders, and it is defined as persistent when it lasts more than 3 months.

Main body

Currently, due to the high prevalence of this disorder, several preclinical studies have been conducted using different animal models of mild TBI to reproduce conditions that engender PTH. Despite representing a simplification of a complex disorder and displaying different limitations concerning the human condition, animal models are still a mainstay to study in vivo the mechanisms of PTH and have provided valuable insight into the pathophysiology and possible treatment strategies. Different models reproduce different types of trauma and have been ideated in order to ensure maximal proximity to the human condition and optimal experimental reproducibility.

Conclusion

At present, despite its high prevalence, PTH is not entirely understood, and the differential contribution of pathophysiological mechanisms, also observed in other conditions like migraine, has to be clarified. Although facing limitations, animal models are needed to improve understanding of PTH. The knowledge of currently available models is necessary to all researchers who want to investigate PTH and contribute to unravel its mechanisms.

Increased severity of closed head injury or repetitive subconcussive head impacts enhances post-traumatic headache-like behaviors in a rat model

INTRODUCTION

Posttraumatic headache is one of the most common, debilitating, and difficult symptoms to manage after a traumatic head injury. The development of novel therapeutic approaches is nevertheless hampered by the paucity of preclinical models and poor understanding of the mechanisms underlying posttraumatic headache. To address these shortcomings, we previously characterized the development of posttraumatic headache-like pain behaviors in rats subjected to a single mild closed head injury using a 250 g weight drop. Here, we conducted a follow-up study to further extend the preclinical research toolbox for studying posttraumatic headache by exploring the development of headache-like pain behaviors in male rats subjected to a single, but more severe head trauma (450 g) as well as following repetitive, subconcussive head impacts (150 g). In addition, we tested whether these behaviors involve peripheral calcitonin gene-related peptide signaling by testing the effect of systemic treatment with an anti-calcitonin gene-related peptide monoclonal antibody (anti-calcitonin gene-related peptide mAb).

METHODS

Adult male Sprague Dawley rats (total n = 138) were subjected to diffuse closed head injury using a weight-drop device, or a sham procedure. Three injury paradigms were employed: A single hit, using 450 g or 150 g weight drop, and three successive 150 g weight drop events conducted 72 hours apart. Changes in open field activity and development of cephalic and extracephalic tactile pain hypersensitivity were assessed up to 42 days post head trauma. Systemic administration of the anti-calcitonin gene-related peptide mAb or its control IgG (30 mg/kg) began immediately after the 450 g injury or the third 150 g weight drop with additional doses given every 6 days subsequently.

RESULTS

Rats subjected to 450 g closed head injury displayed an acute decrease in rearing and increased thigmotaxis, together with cephalic tactile pain hypersensitivity that resolved by 6 weeks post-injury. Injured animals also displayed delayed and prolonged extracephalic tactile pain hypersensitivity that remained present at 6 weeks post-injury. Repetitive subconcussive head impacts using the 150 g weight drop, but not a single event, led to decreased vertical rearing as well as cephalic and extracephalic tactile pain hypersensitivity that resolved by 6 weeks post-injury. Early and prolonged anti-calcitonin gene-related peptide mAb treatment inhibited the development of the cephalic tactile pain hypersensitivity in both the severe and repetitive subconcussive head impact models.

CONCLUSIONS

Severe head injury gives rise to a prolonged state of cephalic and extracephalic tactile pain hypersensitivity. These pain behaviors also develop following repetitive, subconcussive head impacts. Extended cephalic tactile pain hypersensitivity following severe and repetitive mild closed head injury are ameliorated by early and prolonged anti-calcitonin gene-related peptide mAb treatment, suggesting a mechanism linked to calcitonin gene-related peptide signaling, potentially of trigeminal origin.

Persistent Post-Traumatic Headache and Migraine: Pre-Clinical Comparisons

Background: Oftentimes, persistent post traumatic headache (PPTH) and migraine are phenotypically similar and the only clinical feature that differentiate them is the presence of a mild or moderate traumatic brain injury (mTBI). The aim of this study is to describe the differences in brain area and in biochemical cascade after concussion and to define the efficacy and safety of treatments in use. Methods: Sources were chosen in according to the International Classification of Headache Disorder (ICHD) criteria. Results: The articles demonstrated a significant difference between PPTH and migraine regarding static functional connectivity (sFC) and dynamic functional connectivity (dFC) in brain structure that could be used for exploring the pathophysiological mechanisms in PPTH. Many studies described a cascade of neuro-metabolic changes that occur after traumatic brain injury. These variations are associated to the mechanism occurring when developing a PPTH. Conclusions: The state of art of this important topic show how although the mechanisms underlying the development of the two different diseases are different, the treatment of common migraine is efficacious in patients that have developed a post traumatic form.