Vestibular migraine: an update

PURPOSE OF REVIEW

We performed a narrative review of the recent findings in epidemiology, clinical presentation, mechanisms and treatment of vestibular migraine.

RECENT FINDINGS

Vestibular migraine is an underdiagnosed condition that has a high prevalence among general, headache and neuro-otology clinics. Vestibular migraine has a bimodal presentation probably associated with a hormonal component in women. These patients could have a complex clinical phenotype including concomitant autonomic, inflammatory or connective tissue conditions that have a higher prevalence of psychological symptoms, which may mistakenly lead to a diagnosis of a functional neurological disorder. A high proportion of patients with postural perceptual persistent dizziness have a migraine phenotype. Independently of the clinical presentation and past medical history, patients with the vestibular migraine phenotype can respond to regular migraine preventive treatments, including those targeting the calcitonin gene-related peptide pathways.

SUMMARY

Vestibular migraine is an underdiagnosed migraine phenotype that shares the pathophysiological mechanisms of migraine, with growing interest in recent years. A thorough anamnesis is essential to increase sensitivity in patients with unknown cause of dizziness and migraine treatment should be considered (see supplemental video-abstract).

Efficacy and Safety of Erenumab in Participants With Episodic Migraine in Whom 2-4 Prior Preventive Treatments Had Failed: LIBERTY 3-Year Study

BACKGROUND AND OBJECTIVES

The LIBERTY study assessed the efficacy and safety of erenumab in participants with episodic migraine (EM) and 2-4 prior preventive treatment failures. The results have been presented after 3 years of erenumab exposure in its open-label extension phase (OLEP).

METHODS

Participants completing the 12-week double-blind treatment phase (DBTP) of the LIBERTY study could enter the OLEP and receive 140 mg of erenumab once monthly for 3 years. The main outcomes included the proportion of participants achieving ≥50% reduction in monthly migraine days (MMDs), the mean MMD change from baseline, and tolerability and safety.

RESULTS

Overall, 240/246 (97.6%) participants entered the OLEP and 168/240 (70.0%) completed the study (85/118 continuing erenumab [n = 1 lost during follow-up]; 83/122 switching from placebo [n = 2 lost during follow-up]). In the overall population, 79/151 participants (52.3%) with valid data points achieved ≥50% reduction in MMDs at week 168 (i.e., responders). In the continuous erenumab group, 35/117 participants (29.9%) were ≥50% responders at week 12 of the DBTP and 26/35 (74.3%) remained ≥50% responders in at least half of OLEP visits. Of the 82/117 participants (70.1%) not achieving responder status at week 12 in the continuous erenumab group, 17/82 (20.7%) converted to ≥50% responders in at least half of OLEP visits. Of 103/120 participants (85.8%) not achieving responder status at week 12 in the placebo-erenumab group, 42/103 (40.8%) converted to ≥50% responders in at least half of OLEP visits after switching to erenumab. Overall, the mean (SD) MMD change from baseline showed sustained improvement over 3 years (-4.4 [3.9] days at week 168). The most common treatment-emergent AEs (per 100 person-years) were nasopharyngitis (28.8), influenza (7.5), and back pain (5.8). Overall, 9.6% (3.9 per 100 person-years) and 6.7% (2.7 per 100 person-years) of participants reported events of treatment-emergent hypertension and constipation, respectively. The safety and tolerability profile remained consistent with earlier studies.

DISCUSSION

Erenumab (140 mg) showed sustained efficacy over 3 years in participants with EM and 2-4 prior preventive treatment failures. No new safety signals were observed.

TRIAL REGISTRATION INFORMATION

ClinicalTrials.gov Identifier: NCT03096834.

An economic evaluation of eptinezumab for the preventive treatment of migraine in the UK, with consideration for natural history and work productivity

BACKGROUND

Migraine is a highly prevalent neurological disease with a substantial societal burden due to lost productivity. From a societal perspective, we assessed the cost-effectiveness of eptinezumab for the preventive treatment of migraine.

METHODS

An individual patient simulation of discrete competing events was developed to evaluate eptinezumab cost-effectiveness compared to best supportive care for adults in the United Kingdom with ≥ 4 migraine days per month and prior failure of ≥ 3 preventive migraine treatments. Individuals with sampled baseline characteristics were created to represent this population, which comprised dedicated episodic and chronic migraine subpopulations. Clinical efficacy, utility, and work productivity inputs were based on results from the DELIVER randomised controlled trial (NCT04418765). Timing of natural history events and treatment holidays-informed by the literature-were simulated to unmask any natural improvement of the disease unrelated to treatment. The primary outcomes were monthly migraine days, migraine-associated costs, quality-adjusted life years (QALYs), incremental cost-effectiveness ratio, and net monetary benefit, each evaluated over a 5-year time horizon from 2020. Secondary analyses explored a lifetime horizon and an alternative treatment stopping rule.

RESULTS

Treatment with eptinezumab resulted in an average of 0.231 QALYs gained at a saving of £4,894 over 5 years, making eptinezumab dominant over best supportive care (i.e., better health outcomes and less costly). This result was confirmed by the probabilistic analysis and all alternative assumption scenarios under the same societal perspective. Univariate testing of inputs showed net monetary benefit was most sensitive to the number of days of productivity loss, and monthly salary.

CONCLUSIONS

This economic evaluation shows that from a societal perspective, eptinezumab is a cost-effective treatment in patients with ≥ 4 migraine days per month and for whom ≥ 3 other preventive migraine treatments have failed.

TRIAL REGISTRATION

N/A.

Calcitonin gene-related peptide-targeting therapies are a first-line option for the prevention of migraine: An American Headache Society position statement update

OBJECTIVE

To provide a position statement update from The American Headache Society specifically regarding therapies targeting calcitonin gene-related peptide (CGRP) for the prevention of migraine.

BACKGROUND

All migraine preventive therapies previously considered to be first-line treatments were developed for other indications and adopted later for migraine. Adherence to these therapies is often poor due to issues with efficacy and tolerability. Multiple new migraine-specific therapies have been developed based on a broad foundation of pre-clinical and clinical evidence showing that CGRP plays a key role in the pathogenesis of migraine. These CGRP-targeting therapies have had a transformational impact on the management of migraine but are still not widely considered to be first-line approaches.

METHODS

Evidence regarding migraine preventive therapies including primary and secondary endpoints from randomized placebo-controlled clinical trials, post hoc analyses and open-label extensions of these trials, and prospective and retrospective observational studies were collected from a variety of sources including PubMed, Google Scholar, and ClinicalTrials.gov. The results and conclusions based upon these results were reviewed and discussed by the Board of Directors of The American Headache Society to confirm consistency with clinical experience and to achieve consensus.

RESULTS

The evidence for the efficacy, tolerability, and safety of CGRP-targeting migraine preventive therapies (the monoclonal antibodies: erenumab, fremanezumab, galcanezumab, and eptinezumab, and the gepants: rimegepant and atogepant) is substantial, and vastly exceeds that for any other preventive treatment approach. The evidence remains consistent across different individual CGRP-targeting treatments and is corroborated by extensive "real-world" clinical experience. The data indicates that the efficacy and tolerability of CGRP-targeting therapies are equal to or greater than those of previous first-line therapies and that serious adverse events associated with CGRP-targeting therapies are rare.

CONCLUSION

The CGRP-targeting therapies should be considered as a first-line approach for migraine prevention along with previous first-line treatments without a requirement for prior failure of other classes of migraine preventive treatment.

Indomethacin-Responsive Headache Disorders

OBJECTIVE

This article describes the clinical features and treatment of the indomethacin-responsive headache disorders paroxysmal hemicrania and hemicrania continua.

LATEST DEVELOPMENTS

Both paroxysmal hemicrania and hemicrania continua are treated with indomethacin at the lowest clinically useful dose. It has recently become clear that some patients with either condition may respond to treatment with noninvasive vagus nerve stimulation, which can be both indomethacin sparing and, in some cases, headache controlling. Given the lifelong nature of both paroxysmal hemicrania and hemicrania continua, brain imaging with MRI is recommended when the conditions are identified, specifically including pituitary views.

ESSENTIAL POINTS

Paroxysmal hemicrania and hemicrania continua are indomethacin-responsive headache disorders that offer a rewarding and unique opportunity to provide marked clinical improvement when recognized and treated appropriately. These disorders share the final common pathway of the trigeminal-autonomic reflex, with head pain and cranial autonomic features, and are differentiated pathophysiologically by the pattern of brain involvement, which can be seen using functional imaging. They have distinct differential diagnoses to which the clinician needs to remain alert.

Structural equation modeling for identifying the drivers of health-related quality of life improvement experienced by patients with migraine receiving eptinezumab

BACKGROUND

As new migraine therapies emerge, it is crucial for measures to capture the complexities of health-related quality of life (HRQoL) improvement beyond improvements in monthly migraine day (MMD) reduction. Investigations into the correlations between MMD reduction, symptom management, and HRQoL are lacking, particularly those that focus on improvements in canonical symptoms and improvement in patient-identified most-bothersome symptoms (PI-MBS), in patients treated with eptinezumab. This exploratory analysis identified efficacy measures mediating the effect of eptinezumab on HRQoL improvements in patients with migraine.

METHODS

Data from the DELIVER study of patients with 2-4 prior preventive migraine treatment failures (NCT04418765) were inputted to two structural equation models describing sources of HRQoL improvement via Migraine-Specific Quality-of-Life Questionnaire (MSQ) scores. A single latent variable was defined to represent HRQoL and describe the sources of HRQoL in DELIVER. One model included all migraine symptoms while the second model included the PI-MBS as the only migraine symptom. Mediating variables capturing different aspects of efficacy included MMDs, other canonical symptoms, and PI-MBS.

RESULTS

In the first model, reductions in MMDs and other canonical symptoms accounted for 35% (standardized effect size [SES] - 0.11) and 25% (SES - 0.08) of HRQoL improvement, respectively, with 41% (SES - 0.13) of improvement comprising "direct treatment effect," i.e., unexplained by mediators. In the second model, substantial HRQoL improvement with eptinezumab (86%; SES - 0.26) is due to MMD reduction (17%; SES - 0.05) and change in PI-MBS (69%; SES - 0.21).

CONCLUSIONS

Improvements in HRQoL experienced by patients treated with eptinezumab can be substantially explained by its effect on migraine frequency and PI-MBS. Therefore, in addition to MMD reduction, healthcare providers should discuss PI-MBS improvements, since this may impact HRQoL. Health technology policymakers should consider implications of these findings in economic evaluation, as they point to alternative measurement of quality-adjusted life years to capture fully treatment benefits in cost-utility analyses.

TRIAL REGISTRATION

ClinicalTrials.gov (Identifier: NCT04418765 ; EudraCT (Identifier: 2019-004497-25; URL: https://www.clinicaltrialsregister.eu/ctr-search/search?query=2019-004497-25 ).

Melatonin in hemicrania continua and paroxysmal hemicrania

BACKGROUND

Hemicrania continua (HC) and paroxysmal hemicrania (PH) belong to a group of primary headache disorders called trigeminal autonomic cephalalgias. One of the diagnostic criteria for both HC and PH is the absolute response to the therapeutic dose of indomethacin. However, indomethacin is discontinued in many patients as a result of intolerance to its side effects. Melatonin, a pineal hormone, which shares similar chemical structure to indomethacin, has been reported to have some efficacy for HC in previous case reports and series. To our knowledge, there is no literature regarding the use of melatonin in PH. We aimed to describe the clinical use of melatonin in the preventive management of HC and PH.

METHODS

Patient level data were extracted as an audit from routinely collected clinical records in consecutive patients seen in outpatient neurology clinic at King's College Hospital, London, UK, from September 2014 to April 2023. Our cohort of patients were identified through a search using the keywords: hemicrania continua, paroxysmal hemicrania, melatonin and indomethacin. Descriptive statistics including absolute and relative frequencies, mean ± SD, median and interquartile range (IQR) were used.

RESULTS

Fifty-six HC patients were included with a mean ± SD age of 52 ± 16 years; 43 of 56 (77%) patients were female. Melatonin was taken by 23 (41%) patients. Of these 23 patients, 19 (83%) stopped indomethacin because of different side effects. The doses of melatonin used ranged from 0.5 mg to 21 mg, with a median dose of 10 mg (IQR = 6-13 mg). Fourteen (61%) patients reported positive relief for headache, whereas the remaining nine (39%) patients reported no headache preventive effect. None of the patients reported that they were completely pain free. Two patients continued indomethacin and melatonin concurrently for better symptom relief. Eight patients continued melatonin as the single preventive treatment. Side effects from melatonin were rare. Twenty-two PH patients were included with mean ± SD age of 50 ± 17 years; 17 of 22 (77%) patients were female. Melatonin was given to six (27%) patients. The median dose of melatonin used was 8 mg (IQR = 6-10 mg). Three (50%) patients responded to melatonin treatment. One of them used melatonin as adjunctive treatment with indomethacin.

CONCLUSIONS

Melatonin showed some efficacy in the treatment of HC and PH with a well-tolerated side effect profile. It does not have the same absolute responsiveness as indomethacin, at the doses used, although it does offer a well-tolerated option that can have significant ameliorating effects in a substantial cohort of patients.

Comparing the Efficacy and Safety of Galcanezumab Versus Rimegepant for Prevention of Episodic Migraine: Results from a Randomized, Controlled Clinical Trial

INTRODUCTION

There have been no prior trials directly comparing the efficacy of different calcitonin gene-related peptide (CGRP) antagonists for migraine prevention. Reported are the results from the first head-to-head study of two CGRP antagonists, galcanezumab (monoclonal antibody) versus rimegepant (gepant), for the prevention of episodic migraine.

METHODS

In this 3-month, double-blind, double-dummy study, participants were randomized (1:1) to subcutaneous (SC) galcanezumab 120 mg per month (after a 240 mg loading dose) and a placebo oral disintegrating tablet (ODT) every other day (q.o.d.) or to rimegepant 75 mg ODT q.o.d. and a monthly SC placebo. The primary endpoint was the proportion of participants with a ≥ 50% reduction in migraine headache days per month from baseline across the 3-month double-blind treatment period. Key secondary endpoints were overall mean change from baseline in: migraine headache days per month across 3 months and at month 3, 2, and 1; migraine headache days per month with acute migraine medication use; Migraine-Specific Quality of Life Questionnaire Role Function-Restrictive domain score at month 3; and a ≥ 75% and 100% reduction from baseline in migraine headache days per month across 3 months.

RESULTS

Of 580 randomized participants (galcanezumab: 287, rimegepant: 293; mean age: 42 years), 83% were female and 81% Caucasian. Galcanezumab was not superior to rimegepant in achieving a ≥ 50% reduction from baseline in migraine headache days per month (62% versus 61% respectively; P = 0.70). Given the pre-specified multiple testing procedure, key secondary endpoints cannot be considered statistically significant. Overall, treatment-emergent adverse events were reported by 21% of participants, with no significant differences between study intervention groups.

CONCLUSIONS

Galcanezumab was not superior to rimegepant for the primary endpoint; however, both interventions demonstrated efficacy as preventive treatments in participants with episodic migraine. The efficacy and safety profiles observed in galcanezumab-treated participants were consistent with previous studies.

TRIAL REGISTRATION

ClinTrials.gov-NCT05127486 (I5Q-MC-CGBD).

What visuospatial perception has taught us about the pathophysiology of vestibular migraine

PURPOSE OF REVIEW

A decade has passed since vestibular migraine (VM) was formally established as a clinical entity. During this time, VM has emerged amongst the most common cause of episodic vertigo. Like all forms of migraine, VM symptoms are most prominent during individual attacks, however many patients may also develop persistent symptoms that are less prominent and can still interfere with daily activities.

RECENT FINDINGS

Vestibular inputs are strongly multimodal, and because of extensive convergence with other sensory information, they do not result in a distinct conscious sensation. Here we review experimental evidence that supports VM symptoms are linked to multisensory mechanisms that control body motion and position in space.

SUMMARY

Multisensory integration is a key concept for understanding migraine. In this context, VM pathophysiology may involve multisensory processes critical for motion perception, spatial orientation, visuospatial attention, and spatial awareness.

PACAP-38 related modulation of the cranial parasympathetic projection: A novel mechanism and therapeutic target in severe primary headache

BACKGROUND AND PURPOSE

Little is known of how cranial autonomic symptoms (CAS) in cluster headache and migraine may contribute to their severe headache phenotype. This strong association suggests the involvement of the cranial parasympathetic efferent pathway. To investigate its contribution, we studied the role of pituitary adenylate cyclase activating polypeptide-38 (PACAP-38), a potent sensory and parasympathetic neuropeptide, in modulating pre- and post-ganglionic cranial parasympathetic projection neurons, and their influence on headache-related trigeminal-autonomic responses.

EXPERIMENTAL APPROACH

Using PACAP-38 and PACAP-38 responsive receptor antagonists, electrophysiological, behavioural and facial neurovascular-blood flow was measured in rats to probe trigeminal- and parasympathetic-neuronal, periorbital thresholds and cranial-autonomic outcomes, as they relate to primary headaches.

KEY RESULTS

Sumatriptan attenuated the development of PACAP-38 mediated activation and sensitization of trigeminocervical neurons and related periorbital allodynia. PACAP-38 also caused activation and enhanced responses of dural-responsive pre-ganglionic pontine-superior salivatory parasympathetic neurons. Further, the PACAP-38 responsive receptor antagonists dissected a role of VPAC1 and PAC1 receptors in attenuating cranial-autonomic and trigeminal-neuronal responses to activation of the cranial parasympathetic projection, which requires post-ganglionic parasympathetic neurotransmission.

CONCLUSION AND IMPLICATIONS

Given the prevailing view that sumatriptan acts to some degree via a peripheral mechanism, our data support that PACAP-38 mediated receptor activation modulates headache-related cranial-autonomic and trigeminovascular responses via peripheral and central components of the cranial parasympathetic projection. This provides a mechanistic rationale for the association of CAS with more severe headache phenotypes in cluster headache and migraine, and supports the cranial parasympathetic projection as a potential novel locus for treatment by selectively targeting PACAP-38 or PACAP-38 responsive VPAC1 /PAC1 receptors.

Pathophysiology of cluster headache: From the trigeminovascular system to the cerebral networks

BACKGROUND

Despite advances in neuroimaging and electrophysiology, cluster headache's pathogenesis remains unclear. This review will examine clinical neurophysiology studies, including electrophysiological and functional neuroimaging, to determine if they might help us construct a neurophysiological model of cluster headache.

RESULTS

Clinical, biochemical, and electrophysiological research have implicated the trigeminal-parasympathetic system in cluster headache pain generation, although the order in which these two systems are activated, which may be somewhat independent, is unknown. Electrophysiology and neuroimaging have found one or more central factors that may cause seasonal and circadian attacks. The well-known posterior hypothalamus, with its primary circadian pacemaker suprachiasmatic nucleus, the brainstem monoaminergic systems, the midbrain, with an emphasis on the dopaminergic system, especially when cluster headache is chronic, and the descending pain control systems appear to be involved. Functional connection investigations have verified electrophysiological evidence of functional changes in distant brain regions connecting to wide cerebral networks other than pain.

CONCLUSION

We propose that under the impact of external time, an inherited misalignment between the primary circadian pacemaker suprachiasmatic nucleus and other secondary extra- suprachiasmatic nucleus clocks may promote disturbance of the body's internal physiological clock, lowering the threshold for bout recurrence.

Management of cervical CSF-venous fistula causing acute cognitive impairment and coma

CSF-venous fistulas (CVFs) are increasingly recognised as a cause of spontaneous intracranial hypotension. They may present atypically including with brain sagging pseudo-dementia. Cervical CVFs are rare and their management can be difficult due to associated eloquent nerve roots. We report the case of a 49-year-old woman who presented with cognitive decline progressing to coma. Brain imaging showed features of spontaneous intracranial hypotension and a right C7 CVF was identified at digital subtraction and CT myelography. Initial treatment with CT-guided injection of fibrin sealant produced temporary improvement in symptoms before surgical treatment resulted in total clinical remission and radiological resolution.

Ubrogepant for the treatment of migraine attacks during the prodrome: a phase 3, multicentre, randomised, double-blind, placebo-controlled, crossover trial in the USA

BACKGROUND

Ubrogepant is a calcitonin gene-related peptide (CGRP) receptor antagonist that is approved for acute treatment of migraine. The prodrome is the earliest phase of a migraine attack and is characterised by non-aura symptoms that precede headache onset. The aim of this trial was to evaluate the efficacy, safety, and tolerability of ubrogepant 100 mg compared with placebo for the acute treatment of migraine when administered during the prodrome.

METHODS

This PRODROME trial was a phase 3, multicentre, randomised, double-blind, placebo-controlled, crossover trial of ubrogepant 100 mg conducted at 75 research centres and headache clinics in the USA. Eligible participants were adults aged 18-75 years who had at least a 1-year history of migraine with or without aura and a history of two to eight migraine attacks per month with moderate to severe headache in each of the 3 months before screening. Eligible participants were randomly assigned (1:1) to either receive placebo to treat the first qualifying prodrome event and ubrogepant 100 mg to treat the second qualifying prodrome event or to receive ubrogepant 100 mg to treat the first qualifying prodrome event and placebo to treat the second qualifying prodrome event. An automated interactive web-response system used permuted blocks of four to manage randomisation. All people giving interventions and assessing outcomes were masked to group assignment during the study. People doing data analysis, which occurred after study completion, were not masked to group assignment. During the double-blind treatment period, each participant was instructed to orally take two tablets of the study drug at the onset of each qualifying prodrome event. The primary endpoint was absence of moderate or severe intensity headache within 24 h after study-drug dose; efficacy analyses were conducted with the modified intention-to-treat (mITT) population, defined as all randomly assigned participants with at least one headache assessment within 24 h after taking the study drug during the treatment period. The safety population included all treated participants who took at least one administration of study drug. The trial is registered with ClinicalTrials.gov (NCT04492020).

FINDINGS

Between Aug 21, 2020, and April 19, 2022, 518 participants were randomly assigned to double-blind crossover treatment. The safety population included 480 participants and the mITT population included 477 participants; 421 (88%) of 480 participants were female and 59 (12%) were male. Absence of moderate or severe headache within 24 h after a dose occurred after 190 (46%) of 418 qualifying prodrome events that had been treated with ubrogepant and after 121 (29%) of 423 qualifying prodrome events that had been treated with placebo (odds ratio 2·09, 95% CI 1·63-2·69; p<0·0001). Adverse events that occurred within 48 h after study-drug administration were reported after 77 (17%) of 456 qualifying prodrome events that had been treated with ubrogepant and after 55 (12%) of 462 events that had been treated with placebo.

INTERPRETATION

Ubrogepant was effective and well tolerated for the treatment of migraine attacks when taken during the prodrome.

FUNDING

AbbVie.

Effectiveness and safety profile of greater occipital nerve blockade in cluster headache: a systematic review

BACKGROUND

Greater occipital nerve (GON) blockade is a short-term preventive therapy for cluster headache (CH). We conducted a systematic review to evaluate the effectiveness and safety of GON blockade in patients with CH.

METHODS

On 23 October 2020, we searched MEDLINE, Embase, Embase Classic, PsycINFO, CINAHL, CENTRAL and Web of Science databases from their inception date. Studies included participants with a CH diagnosis who received corticosteroid and local anaesthetic suboccipital region injections. Outcomes were change in the frequency/severity/duration of attacks; proportion of participants responding to treatment, time to attack freedom from an attack, change in attack bout length and/or the presence of adverse effects after GON blockade. Risk of bias was assessed with the Cochrane Risk of Bias V.2.0 (RoB2)/Risk of Bias in Non-randomized Studies - of Interventions (ROBINS- I) tools and a specific tool for case reports/series.

RESULTS

Two RCTs, eight prospective and eight retrospective studies, and four case reports were included in the narrative synthesis. Every effectiveness study found a significant response in one or more of frequency/severity/duration of individual attacks or proportion of patients responding to treatment (47.8%-100.0%). There were five instances of potentially irreversible adverse effects. A higher injectate volume and use of concurrent prophylaxis may be associated with an increased likelihood of response. Methylprednisolone may have the best safety profile of available corticosteroids.

DISCUSSION

GON blockade is safe and effective for CH prevention. Higher injectate volumes may improve likelihood of response, and the likelihood of serious adverse events may be reduced by using methylprednisolone.

PROSPERO REGISTRATION NUMBER

CRD42020208435.

Abnormal Glutamatergic and Serotonergic Connectivity in Visual Snow Syndrome and Migraine with Aura

OBJECTIVE

Neuropharmacological changes in visual snow syndrome (VSS) are poorly understood. We aimed to use receptor target maps combined with resting functional magnetic resonance imaging (fMRI) data to identify which neurotransmitters might modulate brain circuits involved in VSS.

METHODS

We used Receptor-Enriched Analysis of Functional Connectivity by Targets (REACT) to estimate and compare the molecular-enriched functional networks related to 5 neurotransmitter systems of patients with VSS (n = 24), healthy controls (HCs; n = 24), and migraine patients ([MIG], n = 25, 15 of whom had migraine with aura [MwA]). For REACT we used receptor density templates for the transporters of noradrenaline, dopamine, and serotonin, GABA-A and NMDA receptors, as well as 5HT1B and 5HT2A receptors, and estimated the subject-specific voxel-wise maps of functional connectivity (FC). We then performed voxel-wise comparisons of these maps among HCs, MIG, and VSS.

RESULTS

Patients with VSS had reduced FC in glutamatergic networks localized in the anterior cingulate cortex (ACC) compared to HCs and patients with migraine, and reduced FC in serotoninergic networks localized in the insula, temporal pole, and orbitofrontal cortex compared to controls, similar to patients with migraine with aura. Patients with VSS also showed reduced FC in 5HT2A -enriched networks, largely localized in occipito-temporo-parietal association cortices. As revealed by subgroup analyses, these changes were independent of, and analogous to, those found in patients with migraine with aura.

INTERPRETATION

Our results show that glutamate and serotonin are involved in brain connectivity alterations in areas of the visual, salience, and limbic systems in VSS. Importantly, altered serotonergic connectivity is independent of migraine in VSS, and simultaneously comparable to that of migraine with aura, highlighting a shared biology between the disorders. ANN NEUROL 2023;94:873-884.

European Academy of Neurology guidelines on the treatment of cluster headache

BACKGROUND AND PURPOSE

Cluster headache is a relatively rare, disabling primary headache disorder with a major impact on patients' quality of life. This work presents evidence-based recommendations for the treatment of cluster headache derived from a systematic review of the literature and consensus among a panel of experts.

METHODS

The databases PubMed (Medline), Science Citation Index, and Cochrane Library were screened for studies on the efficacy of interventions (last access July 2022). The findings in these studies were evaluated according to the recommendations of the European Academy of Neurology, and the level of evidence was established using GRADE (Grading of Recommendations Assessment, Development, and Evaluation).

RECOMMENDATIONS

For the acute treatment of cluster headache attacks, there is a strong recommendation for oxygen (100%) with a flow of at least 12 L/min over 15 min and 6 mg subcutaneous sumatriptan. Prophylaxis of cluster headache attacks with verapamil at a daily dose of at least 240 mg (maximum dose depends on efficacy and tolerability) is recommended. Corticosteroids are efficacious in cluster headache. To reach an effect, the use of at least 100 mg prednisone (or equivalent corticosteroid) given orally or at up to 500 mg iv per day over 5 days is recommended. Lithium, topiramate, and galcanezumab (only for episodic cluster headache) are recommended as alternative treatments. Noninvasive vagus nerve stimulation is efficacious in episodic but not chronic cluster headache. Greater occipital nerve block is recommended, but electrical stimulation of the greater occipital nerve is not recommended due to the side effect profile.

Mental Imagery in Dreams of Congenitally Blind People

It is unclear to what extent the absence of vision affects the sensory sensitivity for oneiric construction. Similarly, the presence of visual imagery in the mentation of dreams of congenitally blind people has been largely disputed. We investigate the presence and nature of oneiric visuo-spatial impressions by analysing 180 dreams of seven congenitally blind people identified from the online database DreamBank. A higher presence of auditory, haptic, olfactory, and gustatory sensation in dreams of congenitally blind people was demonstrated, when compared to normally sighted individuals. Nonetheless, oneiric visual imagery in reports of congenitally blind subjects was also noted, in opposition to some previous studies, and raising questions about the possible underlying neuro-mechanisms.

Atogepant for the preventive treatment of chronic migraine (PROGRESS): a randomised, double-blind, placebo-controlled, phase 3 trial

BACKGROUND

In this study, we aimed to evaluate the efficacy, safety, and tolerability of atogepant for the preventive treatment of chronic migraine.

METHODS

We did this randomised, double-blind, placebo-controlled, phase 3 trial at 142 clinical research sites across the USA, the UK, Canada, China, Czech Republic, Denmark, France, Germany, Italy, Japan, South Korea, Poland, Russia, Spain, Sweden, and Taiwan. Adults aged 18-80 years with a 1-year or longer history of chronic migraine were randomly assigned (1:1:1) to receive oral atogepant 30 mg twice a day, oral atogepant 60 mg once a day, or placebo. The primary endpoint was change from baseline in mean monthly migraine days (MMDs) across the 12-week treatment period. The primary analysis was done in the modified intent-to-treat population and included all randomly assigned participants who received at least one dose of study intervention, had an evaluable baseline period of electronic diary (eDiary) data, and had at least one evaluable post-baseline 4-week period (weeks 1-4, 5-8, and 9-12) of eDiary data during the double-blind period. The safety population consisted of all participants who received at least one dose of study intervention. This trial is registered with ClinicalTrials.gov (NCT03855137).

FINDINGS

Between March 11, 2019 and Jan 20, 2022, 1489 participants were assessed for eligibility. 711 were excluded, and 778 participants were randomly assigned to atogepant 30 mg twice a day (n=257), atogepant 60 mg once a day (n=262), or placebo (n=259). Participants in the safety population were aged 18-74 years (mean 42·1 years). 459 (59%) of 773 patients were White, 677 (88%) patients were female, and 96 (12%) were male. 84 participants discontinued treatment during the trial, and 755 comprised the modified intent-to-treat population (atogepant 30 mg twice a day n=253, atogepant 60 mg once a day n=256, and placebo n=246). Baseline mean number of MMDs were 18·6 (SE 5·1) with atogepant 30 mg twice a day, 19·2 (5·3) with atogepant 60 mg once a day, and 18·9 (4·8) with placebo. Change from baseline in mean MMDs across 12 weeks was -7·5 (SE 0·4) with atogepant 30 mg twice a day, -6·9 (0·4) with atogepant 60 mg once a day, and -5·1 (0·4) with placebo. Least squares mean difference from placebo was -2·4 with atogepant 30 mg twice a day (95% CI -3·5 to -1·3; adjusted p<0·0001) and -1·8 with atogepant 60 mg once a day (-2·9 to -0·8; adjusted p=0·0009). Most common adverse events for atogepant were constipation (30 mg twice a day 28 [10·9%]; 60 mg once a day 26 [10%]; and placebo 8 [3%]) and nausea (30 mg twice a day 20 [8%]; 60 mg once a day 25 [10%]; and placebo 9 [4%]). Potentially clinically significant weight decrease (≥7% reduction at any time post-baseline) was observed in each treatment group (atogepant 30 mg twice a day 14 [6%]; atogepant 60 mg once a day 15 [6%]; and placebo 5 [2%]).

INTERPRETATION

Atogepant 30 mg twice a day and 60 mg once a day showed clinically relevant reductions in MMDs across 12 weeks in chronic migraine patients. Both atogepant doses were well tolerated, consistent with the known safety profile of atogepant.

FUNDING

Allergan (now AbbVie).

Who cares about migraine? Pathways and hurdles in the European region - access to care III

BACKGROUND

Migraine is a highly prevalent primary headache disorder and a leading cause of disability. Difficulties in access to care during diagnostic and therapeutic journey contribute to the disease burden. Several target-specific drugs have reached the market in the past four years and have modified the treatment paradigm in migraine. The aim of this study is to provide an updated snapshot of the pathways and hurdles to care for migraine in different European countries by directly asking patients.

METHODS

In 2021 the European Migraine and Headache Alliance proposed a 39-item questionnaire that was administered online to an adult migraine population in European countries. Questions were focused on socio-demographic and migraine data, access to diagnosis and treatment, disease-related burden and the main channel for disease information.

RESULTS

A total of 3169 questionnaires were returned from 10 European countries. Responders were predominantly females, age range 25-59 years, with a migraine history longer than 10 years in 82% of cases, and with at least 8 headache days per month in 57% of cases. Respondents reported limitations in social, working and personal life during both the ictal and interictal phase. The activities mostly impaired during the attacks were driving (55%), cooking or eating (42%), taking care of family/childcare (40%) and getting medicines at the pharmacy (40%). The most frequently reported unmet need was the long delay between the first visit and migraine diagnosis: 34% of respondents had to see ≥ 4 specialists before being correctly diagnosed, and between the diagnosis and treatment prescription: > 5 years in 40% of cases. The most relevant needs in terms of quality of life were the desire for a lower migraine frequency, an effective treatment and a greater involvement in society.

CONCLUSIONS

Data from the present survey point to the existence and persistence of multiple hurdles that result in significant limitations to access to care and to the patients' social life. A close cooperation between decision makers, healthcare workers and patients is needed to overcome these barriers.

Insights into migraine attacks from neuroimaging

Migraine is one of the most common neurological diseases and it has a huge social and personal impact. Although head pain is the core symptom, individuals with migraine can have a plethora of non-headache symptoms that precede, accompany, or follow the pain. Neuroimaging studies have shown that the involvement of specific brain areas can explain many of the symptoms reported during the different phases of migraine. Recruitment of the hypothalamus, pons, spinal trigeminal nucleus, thalamus, and visual and pain-processing cortical areas starts during the premonitory phase and persists through the headache phase, contributing to the onset of pain and associated symptoms. Once the pain stops, the involvement of most brain areas ends, although the pons, hypothalamus, and visual cortex remain active after acute treatment intake and resolution of migraine symptoms. A better understanding of the correlations between imaging findings and migraine symptomatology can provide new insight into migraine pathophysiology and the mechanisms of novel migraine-specific treatments.

Genetic Mechanisms of Migraine: Insights from Monogenic Migraine Mutations

Migraine is a disabling neurological disorder burdening patients globally. Through the increasing development of preclinical and clinical experimental migraine models, advancing appreciation of the extended clinical phenotype, and functional neuroimaging studies, we can further our understanding of the neurobiological basis of this highly disabling condition. Despite increasing understanding of the molecular and chemical architecture of migraine mechanisms, many areas require further investigation. Research over the last three decades has suggested that migraine has a strong genetic basis, based on the positive family history in most patients, and this has steered exploration into possibly implicated genes. In recent times, human genome-wide association studies and rodent genetic migraine models have facilitated our understanding, but most migraine seems polygenic, with the monogenic migraine mutations being considerably rarer, so further large-scale studies are required to elucidate fully the genetic underpinnings of migraine and the translation of these to clinical practice. The monogenic migraine mutations cause severe aura phenotypes, amongst other symptoms, and offer valuable insights into the biology of aura and the relationship between migraine and other conditions, such as vascular disease and sleep disorders. This review will provide an outlook of what is known about some monogenic migraine mutations, including familial hemiplegic migraine, familial advanced sleep-phase syndrome, and cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy.

Neuroimaging in the pre-ictal or premonitory phase of migraine: a narrative review

BACKGROUND

The premonitory phase, or prodrome, of migraine, provides valuable opportunities to study attack initiation and for treating the attack before headache starts. Much that has been learned about this phase in recent times has come from the outcomes of functional imaging studies. This review will summarise these studies to date and use their results to provide some feasible insights into migraine neurobiology.

MAIN BODY

The ability to scan repeatedly a patient without radiation and with non-invasive imaging modalities, as well as the recognition that human experimental migraine provocation compounds, such as nitroglycerin (NTG) and pituitary adenylate cyclase activating polypeptide (PACAP), can trigger typical premonitory symptoms (PS) and migraine-like headache in patients with migraine, have allowed feasible and reproducible imaging of the premonitory phase using NTG. Some studies have used serial scanning of patients with migraine to image the migraine cycle, including the 'pre-ictal' phase, defined by timing to headache onset rather than symptom phenotype. Direct observation and functional neuroimaging of triggered PS have also revealed compatible neural substrates for PS in the absence of headache. Various imaging methods including resting state functional MRI (rsfMRI), arterial spin labelling (ASL), positron emission tomography (PET) and diffusion tensor imaging (DTI) have been used. The results of imaging the spontaneous and triggered premonitory phase have been largely consistent and support a theory of central migraine attack initiation involving brain areas such as the hypothalamus, midbrain and limbic system. Early dysfunctional pain, sensory, limbic and homeostatic processing via monoaminergic and peptidergic neurotransmission likely manifests in the heterogeneous PS phenotype.

CONCLUSION

Advances in human migraine research, including the use of functional imaging techniques lacking radiation or radio-isotope exposure, have led to an exciting opportunity to study the premonitory phase using repeated measures imaging designs. These studies have provided novel insights into attack initiation, migraine neurochemistry and therapeutic targets. Emerging migraine-specific therapies, such as those targeting calcitonin gene-related peptide (CGRP), are showing promise acutely when taken during premonitory phase to reduce symptoms and prevent subsequent headache. Therapeutic research in this area using PS for headache onset prediction and early treatment is likely to grow in the future.

Molecular Mechanisms of Migraine: Nitric Oxide Synthase and Neuropeptides

Migraine is a common condition with disabling attacks that burdens people in the prime of their working lives. Despite years of research into migraine pathophysiology and therapeutics, much remains to be learned about the mechanisms at play in this complex neurovascular condition. Additionally, there remains a relative paucity of specific and targeted therapies available. Many sufferers remain underserved by currently available broad action preventive strategies, which are also complicated by poor tolerance and adverse effects. The development of preclinical migraine models in the laboratory, and the advances in human experimental migraine provocation, have led to the identification of key molecules likely involved in the molecular circuity of migraine, and have provided novel therapeutic targets. Importantly, the identification that vasoconstriction is neither necessary nor required for headache abortion has changed the landscape of migraine treatment and has broadened the therapy targets for patients with vascular risk factors or vascular disease. These targets include nitric oxide synthase (NOS) and several neuropeptides that are involved in migraine. The ability of NO donors and infusion of some of these peptides into humans to trigger typical migraine-like attacks has supported the development of targeted therapies against these molecules. Some of these, such as those targeting calcitonin gene-related peptide (CGRP), have already reached clinical practice and are displaying a positive outcome in migraineurs for the better by offering targeted efficacy without significant adverse effects. Others, such as those targeting pituitary adenylate cyclase activating polypeptide (PACAP), are showing promise and are likely to enter phase 3 clinical trials in the near future. Understanding these nitrergic and peptidergic mechanisms in migraine and their interactions is likely to lead to further therapeutic strategies for migraine in the future.

Estimating treatment effects on health utility scores for patients living with migraine: a post hoc analysis of the DELIVER trial

BACKGROUND

This post hoc analysis aimed to estimate eptinezumab's therapeutic effect on health utilities and determined to which extent monthly migraine days (MMDs) explain changes in health utilities.

RESEARCH DESIGN/METHODS

DELIVER, a randomized, double-blind, placebo-controlled phase 3b trial (NCT04418765), investigated eptinezumab efficacy and safety in patients with 2-4 prior migraine treatment failures. Regression analysis explored the relationship between utility scores and MMDs, with eptinezumab treatment as a covariate along with MMDs to identify any MMD-independent effect on utilities. Path analysis quantified eptinezumab's impact as mediated through MMD reduction.

RESULTS

The base case model showed that each reduction in MMD was associated with a mean utility score increase (0.0189; 95% CI: 0.0180, 0.0198; P < 0.001). Mean utility score was generally higher for eptinezumab versus placebo, justifying addition of treatment effect to the base case model. Patients administered eptinezumab had on average 0.0562 (95% CI: 0.0382, 0.0742; P < 0.001) higher utility versus placebo when controlling for number of MMDs. From path analysis, MMD reduction resulting from eptinezumab treatment accounted for 53% additional utility gain observed in patients.

CONCLUSIONS

Changes in MMDs alone inadequately captured migraine's impact on patient utility, as there was also a positive eptinezumab-driven, treatment-specific impact on utility score.

TRIAL REGISTRATION

The trial is registered at ClinicalTrials.gov (CT.gov identifier: NCT04418765).

Visuo-spatial imagery in dreams of congenitally and early blind: a systematic review

Background

The presence of visual imagery in dreams of congenitally blind people has long been a matter of substantial controversy. We set to systematically review body of published work on the presence and nature of oneiric visuo-spatial impressions in congenitally and early blind subjects across different areas of research, from experimental psychology, functional neuroimaging, sensory substitution, and sleep research.

Methods

Relevant studies were identified using the following databases: EMBASE, MEDLINE and PsychINFO.

Results

Studies using diverse imaging techniques and sensory substitution devices broadly suggest that the "blind" occipital cortex may be able to integrate non-visual sensory inputs, and thus possibly also generate visuo-spatial impressions. Visual impressions have also been reported by blind subjects who had near-death or out-of-body experiences.

Conclusion

Deciphering the mechanistic nature of these visual impression could open new possibility in utilization of neuroplasticity and its potential role for treatment of neurodisability.

Revisiting dose-finding of monoclonal antibodies in migraine

Migraine is a debilitating disorder, and while the introduction of monoclonal antibodies (mAbs) has led to efficacious and tolerable responses, a substantial number of patients are so-called "non-responders". We introduce reasons for this insufficient response, including insufficient blockade of Calcitonin Gene-Related Peptide (CGRP) or its receptor. We present a clinical case, i.e. a female migraine patient who mistakenly administered supratherapeutic (three-fold higher) doses of erenumab leading to more efficacious clinical responses without any side-effects. This example illustrates that the initial dosages might have been too low, resulting in a remaining undesired increased effect of CGRP. While a capsaicin forearm model has repeatedly been used to evaluate the pharmacokinetic-pharmacodynamic relationship of mAbs, we provide directions to revisit or reconsider dose-finding and dose-ranging of these drugs. These directions include (i) refinement and application of a capsaicin forehead model (instead of a forearm model) to study trigeminovascular activity and improve dosing, and (ii) reconsideration of trial populations. Indeed, the dose-finding studies were mainly performed in relatively young and normal-weight males, while most phase III/IV trials are marked by a high female-to-male ratio, mainly consisting of overweight to obese females. Considering these aspects in future trials could optimize healthcare for a larger proportion of migraine patients.

Regional cerebral perfusion during the premonitory phase of triggered migraine: A double-blind randomized placebo-controlled functional imaging study using pseudo-continuous arterial spin labeling

OBJECTIVE

To identify changes in regional cerebral blood flow (CBF) associated with premonitory symptoms (PS) of nitroglycerin (NTG)-triggered migraine attacks.

BACKGROUND

PS could provide insights into attack initiation and alterations in neuronal function prior to headache onset.

METHODS

We undertook a functional imaging study using a double-blind placebo-controlled randomized approach in patients with migraine who spontaneously experienced PS, and in whom PS and migraine-like headache could be induced by administration of NTG. All study visits took place in a dedicated clinical research facility housing a monitoring area with clinical beds next to a 3Tesla magnetic resonance imaging scanner. Fifty-three patients with migraine were enrolled; imaging on at least one triggered visit was obtained from 25 patients, with 21 patients completing the entire imaging protocol including a placebo visit. Whole brain CBF maps were acquired using 3D pseudo-continuous arterial spin labeling (3D pCASL).

RESULTS

The primary outcome was that patients with migraine not taking preventive treatment (n = 12) displayed significant increases in CBF in anterior cingulate cortex, caudate, midbrain, lentiform, amygdala and hippocampus (p < 0.05 family-wise error-corrected) during NTG-induced PS. A separate region of interest analysis revealed significant CBF increases in the region of the hypothalamus (p = 0.006, effect size 0.77). Post hoc analyses revealed significant reductions in CBF over the occipital cortices in participants with a history of migraine with underlying aura (n = 14).

CONCLUSIONS

We identified significant regional CBF changes associated with NTG-induced PS, consistent with other investigations and with novel findings, withstanding statistical comparison against placebo. These findings were not present in patients who continually took preventive medication. Additional findings were identified only in participants who experience migraine with aura. Understanding this biological and treatment-related heterogeneity is vital to evaluating functional imaging outcomes in migraine research.

Two-year, real-world erenumab persistence and quality of life data in 82 pooled patients with abrupt onset, unremitting, treatment refractory headache and a migraine phenotype: New daily persistent headache or persistent post-traumatic headache in the majority of cases

BACKGROUND

Patients diagnosed with New Daily Persistent Headache and Persistent Post-Traumatic Headache belong to a heterogeneous group of primary and secondary headache disorders, with the common clinical feature that these conditions start abruptly, continue unabated, and are refractory to conventional migraine preventive treatments.

OBJECTIVE

This is a real-world, medium-term audit to explore whether erenumab improves quality of life in a pooled group of 82 abrupt-onset, unremitting and treatment refractory patients, where the diagnosis is new daily persistent headache and persistent post-traumatic headache in the majority of cases.

METHODS

Eighty-two patients were treated with erenumab every 28 days over a two to three-year period, beginning in December 2018. These patients were "longstanding chronic" and refractory with a median of eight (IQR 4-12) prior failed migraine preventive treatments and median duration of disease of seven (IQR 3-11) years. The starting dose of erenumab was 70 mg in 79% of cases and 140 mg in the remaining patients (individuals with a BMI of more than 30). All patients were asked to complete three migraine specific Quality of Life questionnaires or Patient Reported Outcome Measures before starting treatment and typically at 3-12 intervals until the end of June 2021 or cessation of treatment. The Patient Reported Outcome Measures included: Headache Impact Test-6, Migraine Associated Disability Assessment test and Migraine-Specific Quality-of-Life Questionnaire. Patients generally only stayed on treatment after 6-12 months if there was deemed to be an improvement of at least 30% and there were no significant side effects. The longest treated cases have quality of life data for 30 months after starting erenumab.

RESULTS

Of the 82 patients, 29 (35%) had improvement in Quality of Life scores, with no significant side effects, and wished to stay on treatment. Fifty-three patients (65%) stopped treatment during the first 6-25 months due to lack of efficacy and/or patient reported side effects (n = 33 and n = 17, respectively) or a combination of both, pregnancy planning (n = 2), and lost to follow up (n = 1).

CONCLUSION

Significant improvements in Quality of Life scores were recorded by one-third of patients over a period of 11-30 months, with a 35% persistence after a median of 26 months of treatment. This contrasts with our recently published, treatment resistant, chronic migraine cohort where the persistence with erenumab treatment was almost 55% after a median time of 25 months.

Migraine: from pathophysiology to treatment

Migraine is an extremely disabling, common neurological disorder characterized by a complex neurobiology, involving a series of central and peripheral nervous system areas and networks. A growing increase in the understanding of migraine pathophysiology in recent years has facilitated translation of that knowledge into novel treatments, which are currently becoming available to patients in many parts of the world and are substantially changing the clinical approach to the disease. In the first part of this review, we will provide an up to date overview of migraine pathophysiology by analyzing the anatomy and function of the main regions involved in the disease, focusing on how these give rise to the plethora of symptoms characterizing the attacks and overall disease. The second part of the paper will discuss the novel therapeutic agents that have emerged for the treatment of migraine, including molecules targeting calcitonin gene-related peptide (gepants and monoclonal antibodies), serotonin 5-HT_1F receptor agonists (ditans) and non-invasive neuromodulation, as well as providing a brief overview of new evidence for classic migraine treatments.

Eptinezumab improved patient-reported outcomes and quality of life in patients with migraine and prior preventive treatment failures

BACKGROUND AND PURPOSE

In the phase 3b, randomized, double-blind, placebo-controlled DELIVER clinical trial, eptinezumab reduced migraine frequency and headache in adults with two to four prior preventive treatment failures. Here, the effect of eptinezumab on coinciding patient-reported outcomes is reported.

METHODS

Adults were randomized to receive eptinezumab 100, 300 mg or placebo intravenously at weeks 12 and 24. The EQ-5D-5L, measuring overall patient health, and the six-item Headache Impact Test were completed every 4 weeks. The Patient Global Impression of Change was completed at weeks 4, 12 and 24. Patient-identified most bothersome symptom and the Migraine-Specific Quality of Life Questionnaire were administered at weeks 12 and 24.

RESULTS

Eptinezumab improved patient-reported outcomes more than placebo, starting at week 4 and at all subsequent time points. By week 12, patients' overall health (EQ-5D-5L visual analog scale score) improved with eptinezumab treatment (difference from placebo in change from baseline: 100 mg, 5.1, 95% confidence interval [CI] 2.2, 8.1, p < 0.001; 300 mg, 7.5, 95% CI 4.5, 10.4, p < 0.0001). At week 12, eptinezumab improved headache-related quality of life (difference from placebo in change from baseline in Headache Impact Test total score: 100 mg, -3.8, 95% CI -5.0, -2.5, p < 0.0001; 300 mg, -5.4, 95% CI -6.7, -4.2, p < 0.0001), including each Migraine-Specific Quality of Life Questionnaire domain (p ≤ 0.0001, all comparisons). Over twice as many patients receiving eptinezumab than placebo reported much or very much improvement on the Patient Global Impression of Change and patient-identified most bothersome symptom.

CONCLUSION

Patients with two to four prior preventive treatment failures receiving eptinezumab versus placebo reported greater improvements in well-being, quality of life and most bothersome symptoms compared to placebo.

TRIAL REGISTRATION

ClinicalTrials.gov identifier: NCT04418765; EudraCT identifier: 2019-004497-25.

Non-invasive neuromodulation of the cervical vagus nerve in rare primary headaches

Primary headache disorders can be remarkably disabling and the therapeutic options available are usually limited to medication with a high rate of adverse events. Here, we discuss the mechanism of action of non-invasive vagal nerve stimulation, as well as the findings of the main studies involving patients with primary headaches other than migraine or cluster headache, such as hemicrania continua, paroxysmal hemicrania, cough headache, or short-lasting neuralgiform headache attacks (SUNCT/SUNA), in a narrative analysis. A bibliographical search of low-prevalence disorders such as rare primary headaches retrieves a moderate number of studies, usually underpowered. Headache intensity, severity, and duration showed a clinically significant reduction in the majority, especially those involving indomethacin-responsive headaches. The lack of response of some patients with a similar diagnosis could be due to a different stimulation pattern, technique, or total dose. The use of non-invasive vagal nerve stimulation for the treatment of primary headache disorders represents an excellent option for patients with these debilitating and otherwise refractory conditions, or that cannot tolerate several lines of preventive medication, and should always be considered before contemplating invasive, non-reversible stimulation techniques.

Efficacy, safety and indirect comparisons of lasmiditan, rimegepant, and ubrogepant for the acute treatment of migraine: A systematic review and network meta-analysis of the literature

BACKGROUND

We performed a random-effects network meta-analysis to study the efficacy and safety of newly developed drugs for the acute treatment of migraine attacks.

METHODS

MEDLINE via PubMed, Embase and The Cochrane Register of Controlled Trials were searched from inception to 11 February 2022. Phase 3 randomized controlled trials examining all formulations of lasmiditan, rimegepant and ubrogepant for the acute treatment of adults with migraine, were included. Data were extracted following the PRISMA guidelines.

RESULTS

Seven studies (SAMURAI, SPARTAN, CENTURION, Study 302, Study 303, ACHIEVE I and II) involving n = 12,859 patients were included. All treatments were superior in efficacy to placebo. Lasmiditan 200 mg showed the highest two-hour pain freedom, while two-hour freedom from most bothersome symptom was equally achieved by the higher doses of lasmiditan (100 and 200 mg), rimegepant and the higher doses of ubrogepant (50 and 100 mg). The odds of treatment-emergent adverse events were greatest with all doses of lasmiditan.

CONCLUSION

Lasmiditan 200 mg was the most effective intervention in the treatment of migraine attacks, although it was associated with high degrees of dizziness, nausea and somnolence. Rimegepant showed slightly lower, but similar efficacy rates to lasmiditan. Ubrogepant had overall the best tolerability profile. These conclusions are limited by the absence of head-to-head comparisons, limitations of individual trials and of the meta-analysis methodology itself.PROSPERO trial registration: CRD42022308224.

Patient-reported experiences with migraine-related cognitive symptoms: Results of the MiCOAS qualitative study

OBJECTIVES

To capture patients' perspectives on migraine-related cognitive symptoms during pre-headache, headache, post-headache, and interictal periods.

BACKGROUND

Migraine-related cognitive symptoms are reported by people with migraine both during and between attacks. Associated with disability, they are increasingly viewed as a priority target for treatment. The Migraine Clinical Outcome Assessment System (MiCOAS) project is focused on developing a patient-centered core set of outcome measures for the evaluation of migraine treatments. The project focuses on incorporating the experience of people living with migraine and the outcomes most meaningful to them. This includes an examination of the presence and functional impact of migraine-related cognitive symptoms and their perceived impact on quality of life and disability.

METHODS

Forty individuals with self-reported medically diagnosed migraine were recruited via iterative purposeful sampling for semi-structured qualitative interviews conducted using audio-only web conferencing. Thematic content analysis was performed to identify key concepts around migraine-related cognitive symptoms. Recruitment continued until concept saturation was achieved.

RESULTS

Participants described symptoms consistent with migraine-related deficits in language/speech, sustained attention, executive function, and memory that manifest during pre-headache (36/40 [90%] reported ≥1 cognitive feature), headache (35/40 [88%] reported ≥1 cognitive feature), post-headache (27/40 [68%] reported ≥1 cognitive feature), and interictal periods (13/40 [33%] reported ≥1 cognitive feature). Among participants reporting cognitive symptoms during pre-headache, 32/40 (81%) endorsed 2-5 cognitive symptoms. Findings were similar during the headache phase. Participants reported language/speech problems consistent with, for example, impairments in receptive language, expressive language, and articulation. Issues with sustained attention included fogginess, confusion/disorientation, and trouble with concentration/focus. Deficits in executive function included difficulty processing information and reduced capacity for planning and decision-making. Memory issues were reported across all phases of the migraine attack.

CONCLUSIONS

This patient-level qualitative study suggests that cognitive symptoms are common for persons with migraine, particularly in the pre-headache and headache phases. These findings highlight the importance of assessing and ameliorating these cognitive problems.

Safety, tolerability, and efficacy of zavegepant 10 mg nasal spray for the acute treatment of migraine in the USA: a phase 3, double-blind, randomised, placebo-controlled multicentre trial

BACKGROUND

Intranasal formulations can provide treatment options for people with migraine in whom oral drugs are ineffective, slow-acting, or intolerable because of nausea and vomiting. Zavegepant, an intranasally administered small molecule calcitonin gene-related peptide (CGRP) receptor antagonist, was previously assessed in a phase 2/3 trial. This phase 3 trial aimed to compare the efficacy, tolerability, safety, and timecourse of response for zavegepant nasal spray with placebo in the acute treatment of migraine.

METHODS

This double-blind, randomised, placebo-controlled, multicentre phase 3 trial, conducted at 90 academic medical centres, headache clinics, and independent research facilities in the USA, recruited adults (aged ≥18 years) with a history of two to eight moderate or severe migraine attacks per month. Participants were randomly assigned (1:1) to zavegepant 10 mg nasal spray or matching placebo and self-treated a single migraine attack of moderate or severe pain intensity. Randomisation was stratified by the use or non-use of preventive medication. Study centre personnel entered eligible participants into the study using an interactive web response system that was operated and managed by an independent contract research organisation. All participants, investigators, and the funder were masked to group assignment. The coprimary endpoints, freedom from pain and freedom from the most bothersome symptom at 2 h after the treatment dose, were assessed in all randomly assigned participants who took the study medication, had a migraine attack of moderate or severe pain intensity at baseline, and provided at least one evaluable post-baseline efficacy datapoint. Safety was analysed in all randomly assigned participants who received at least one dose. The study is registered with ClinicalTrials.gov, number NCT04571060, and is closed to accrual.

FINDINGS

Between Oct 27, 2020, and Aug 20, 2021, 1978 participants were recruited and assessed for eligibility. 1405 participants were eligible (703 were assigned to zavegepant and 702 to placebo), and 1269 were included in the efficacy analysis set (623 in the zavegepant group and 646 in the placebo group). 2 h after the treatment dose, more participants in the zavegepant group than in the placebo group had pain freedom (147 [24%] of 623 participants vs 96 [15%] of 646 participants, risk difference 8·8 percentage points, 95% CI 4·5-13·1; p<0·0001) and freedom from their most bothersome symptom (247 [40%] vs 201 [31%], risk difference 8·7 percentage points, 3·4-13·9; p=0·0012). The most common adverse events in either treatment group (≥2%) were dysgeusia (129 [21%] of 629 in the zavegepant group vs 31 [5%] of 653 in the placebo group), nasal discomfort (23 [4%] vs five [1%]), and nausea (20 [3%] vs seven [1%]). No signal of hepatotoxicity due to zavegepant was identified.

INTERPRETATION

Zavegepant 10 mg nasal spray was efficacious in the acute treatment of migraine, with favourable tolerability and safety profiles. Additional trials are needed to establish the long-term safety and consistency of effect across attacks.

FUNDING

Biohaven Pharmaceuticals.

Peripheral brain-derived neurotrophic factor (BDNF) in insomnia: A systematic review and meta-analysis

The brain-derived neurotrophic factor (BDNF) is associated with emotional and cognitive functioning, and it is considered a transdiagnostic biomarker for mental disorders. Literature on insomnia related BDNF changes yielded contrasting results and it has never been synthetized using meta-analysis. To fill this gap, we conducted a systematic review and meta-analysis of case-control studies examining the levels of peripheric BDNF in individuals with insomnia and healthy controls using the PRISMA guidelines. PubMed, Scopus, Medline, PsycINFO and CINAHL were searched up to Nov 2022. Nine studies met the inclusion criteria and were assessed using the Newcastle-Ottawa Scale. Eight studies reported sufficient data for meta-analysis. Random-effects models showed lower BDNF in subjects with insomnia (n = 446) than in controls (n = 706) (Hedge's g = -0.86, 95% CI: -1.39 to -0.32, p = .002). Leave-one-out sensitivity analysis confirmed that the pooled effect size was robust and not driven by any single study. However, given the small sample size, the cross-sectional nature of the measurement, and the high heterogeneity of included data, the results should be cautiously interpreted. Progress in the study of BDNF in insomnia is clinically relevant to better understand the mechanisms that may explain the relationship between disturbed sleep and mental disorders.

Alopecia as an emerging adverse event to CGRP monoclonal antibodies: Cases Series, evaluation of FAERS, and literature review

BACKGROUND

Alopecia is associated with erenumab post-marketing, but no cases have been described.

METHODS

We describe two patients that reported temporary hair loss and review the FDA Adverse Event Reporting System (FAERS).

RESULTS

The first patient experienced alopecia within three months of starting erenumab, which did not improve with ongoing use or transition to fremanezumab. The second patient reported alopecia within two weeks of starting erenumab, which continued after transition to galcanezumab; months later, there was also recurrent hair loss within one month of starting fremanzeumab. According to FAERS (last accessed 18 August 2022), alopecia was reported most with erenumab (1158), followed by galcanezumab (554), fremanezumab (175), eptinezumab (23), rimegepant (26), ubrogepant (4), and atogepant (3).

CONCLUSION

Most events were reported in women and non-serious. The potential mechanism of alopecia with drugs targeting calcitonin gene-related peptide or its receptor possibly includes disruptions in the microvascular circulation and other homeostatic mechanisms.

Efficacy of rimegepant for the acute treatment of migraine based on triptan treatment experience: Pooled results from three phase 3 randomized clinical trials

BACKGROUND

This post-hoc analysis from three phase 3 treatment trials of rimegepant 75 mg - an oral small molecule calcitonin gene-related peptide receptor antagonist for acute and preventive treatment of migraine - assessed efficacy in adults with migraine based on triptan treatment experience.

METHODS

Participants were assigned to one of four groups based on triptan treatment experience: insufficient response (e.g. lack of efficacy and/or poor tolerability) to 1 triptan, insufficient response to ≥2 triptans, current triptan users, and triptan-naïve participants. The co-primary efficacy endpoints were pain freedom and most bothersome symptom freedom at two hours postdose.

RESULTS

In the three trials (N = 3507; rimegepant n = 1749, placebo n = 1758), 1235 (35.2%) participants had a history of insufficient response to 1 triptan (n = 910 [25.9%]) or ≥2 triptans (n = 325 [9.3%]), and 2272 (64.8%) had no history of insufficient response to triptans (current use = 595 [17.0%], naïve = 1677 [47.8%]). Rimegepant was effective on the co-primary endpoints in all subgroups (p ≤ 0.013), except for freedom from the most bothersome symptom in the triptan-naïve group (p = 0.06). No differences on co-primary endpoints were found in pairwise comparisons of rimegepant-treated participants.

CONCLUSIONS

Rimegepant was effective for the acute treatment of migraine in adults with a history of insufficient response to 1 or ≥2 triptans and in current triptan users. Efficacy on co-primary endpoints did not differ based on the number of insufficient triptan responses.Trial registration: Clinicaltrials.gov: NCT03235479, NCT03237845, NCT03461757.

Post-vaccination headache reporting: Trends according to the Vaccine Adverse Events Reporting System

OBJECTIVE

To assess the characteristics and associated disability of headache as an adverse event following vaccination.

BACKGROUND

According to clinical trials and post-licensure surveillance, headache is a common symptom of vaccines, yet systematic investigations of post-licensure reports of this adverse event are lacking.

METHODS

This was a retrospective database analysis study. We searched the Vaccine Adverse Events Reporting System (VAERS) database completed from July 1990 to June 2020 (a 30-year period prior to the start of COVID-19 pandemic) to identify reports of headache. We evaluated epidemiological features, including event characteristics, patient demographics, and vaccine type.

RESULTS

In those aged 3 years or older, headache was the fifth most reported adverse symptom, present in 8.1% (43,218/536,120) of all reports. Of headache reports, 96.3% (41,635/43,218) included the code "headache" not further specified. Migraine was coded in 1973 cases, although almost one-third (12,467/41,808; 29.8%) of headache reports without a migraine code mention nausea or vomiting. The onset of symptoms was within 1 day of vaccination in over two-thirds of cases. The majority of reports were classified as not serious; about one-third involved emergency room or office visits. Of the 43,218 total headache reports, only a minority involved hospitalizations (2624; 6.1%) or permanent disability (1091; 2.5%), females accounted for 68.9% (29,771) and males for 29.5% (12,725), patients aged 6 to 59 years represented 67.3% (29,112), and over one-third of cases were reported after herpes zoster (8665; 20.1%) and influenza (6748; 15.6%) vaccinations.

CONCLUSION

In a national surveillance system, headache was a commonly reported post-vaccination adverse event; a small subset of reports was considered serious. The development of standardized vaccine-related case definitions could be useful for better evaluating headache as an adverse event during vaccine development, and may reduce vaccine hesitancy especially in headache-prone individuals.

Medium-term real-world data for erenumab in 177 treatment resistant or difficult to treat chronic migraine patients: persistence and patient reported outcome measures after 17-30 months

BACKGROUND

Many migraine patients do not respond adequately to conventional preventive treatments and are therefore described as treatment/medically resistant or difficult to treat cases. Calcitonin gene-related peptide monoclonal antibodies are a relatively novel molecular treatment for episodic and chronic migraine that have been shown to be effective in short duration clinical trials in approximately 40-50% of all chronic migraine patients. Patient Related Outcome Measures (PROM) or Quality of Life (QoL) questionnaires are used to help measure response to treatment in migraine. Although some open label extension studies have become available for erenumab, there is a lack of real-world data pertaining to quality of life in the medium to long-term for chronic and treatment resistant migraine patients.

METHODS

A total of 177 treatment resistant CM patients were started on erenumab (70 mg or 140 mg subcutaneous injection every 4 weeks) in our three specialist Headache Clinics. Of these, 174 had their first injection between December 2018 and October 2019. All patients were evaluated with the following PROM: the Headache Impact Test- 6, Migraine Associated Disability Assessment test and Migraine-Specific QoL Questionnaire, before starting treatment with erenumab and at intervals of 3-12 months after starting treatment. The decision to continue treatment was based on subjective clinical improvement of at least 30% (as reported by the patient), supported with diaries and QoL questionnaires. We present here the QoL measurements for this group of 177 patients. Prior preventive migraine treatments included conventional oral prophylactic medications (such as topiramate, candesartan, propranolol, or amitriptyline), at least two cycles of PREEMPT protocol onabotulinumtoxin A or (in a small number of cases) neuromodulation with single pulse Transcranial Magnetic Stimulation.

RESULTS

Of the 177 patients who started treatment with erenumab, 68/177 (38.4%) stopped during the first year, either due to lack of efficacy (no significant benefit or only minimal improvement) and/or possible side effects. 109/177 (61.6%) patients reported clinically significant improvement after 6-12 months and wished to stay on treatment. Twelve of these 109 patients subsequently stopped treatment in the period between 1 year and up to June 2021 (mainly due to a worsening of their migraine). Therefore, a total of 97/177 patients (54.8%) remained on treatment as of June 2021 (duration of treatment 17-30 months, median of 25 months).

CONCLUSION

Approximately 55% of treatment resistant or difficult to treat CM patients who trialled erenumab in our clinics reported a subjective benefit and were still on treatment after 17-30 months.

Evaluating migraine with typical aura with neuroimaging

Objective

To provide an up-to-date narrative literature review of imaging in migraine with typical aura, as a means to understand better migraine subtypes and aura biology.

Background

Characterizing subtypes of migraine with typical aura and appreciating possible biological differences between migraine with and without aura, are important to understanding the neurobiology of aura and trying to advance personalized therapeutics in this area through imaging biomarkers. One means of doing this over recent years has been the use of increasingly advanced neuroimaging techniques.

Methods

We conducted a literature review of neuroimaging studies in migraine with aura, using a PubMed search for terms 'imaging migraine', 'aura imaging', 'migraine with aura imaging', 'migraine functional imaging' and 'migraine structural imaging'. We collated the findings of the main studies, excluding small case reports and series with n < 6, and have summarized these and their implications for better understanding of aura mechanisms.

Results

Aura is likely mediated by widespread brain dysfunction in areas involving, but not limited to, visual cortex, somatosensory and insular cortex, and thalamus. Higher brain excitability in response to sensory stimulation and altered resting-state functional connectivity in migraine sufferers with aura could have a genetic component. Pure visual aura compared to visual aura with other sensory or speech symptoms as well, may involve different functional reorganization of brain networks and additional mitochondrial dysfunction mediating more aura symptoms.

Conclusion

There is a suggestion of at least some distinct neurobiological differences between migraine with and without aura, despite the shared phenotypic similarity in headache and other migraine-associated symptoms. It is clear from the vast majority of aura phenotypes being visual that there is a particular predisposition of the occipital cortex to aura mechanisms. Why this is the case, along with the relationships between cortical spreading depression and headache, and the reasons why aura does not consistently present in affected individuals, are all important research questions for the future.

Headache attributed to SARS-CoV-2 infection, vaccination and the impact on primary headache disorders of the COVID-19 pandemic: A comprehensive review

OBJECTIVE

The objective is to summarize the knowledge on the epidemiology, pathophysiology and management of secondary headache attributed to SARS-CoV-2 infection and vaccination; as well as to delineate their impact on primary headache disorders.

METHODS

This is a narrative review of the literature regarding primary and secondary headache disorders in the setting of COVID-19 pandemic. We conducted a literature search in 2022 on PubMed, with the keywords "COVID 19" or "vaccine" and "headache" to assess the appropriateness of all published articles for their inclusion in the review.

RESULTS

Headache is a common and sometimes difficult-to-treat symptom of both the acute and post-acute phase of SARS-CoV-2 infection. Different pathophysiological mechanisms may be involved, with the trigeminovascular system as a plausible target. Specific evidence-based effective therapeutic options are lacking at present. Headache attributed to SARS-CoV-2 vaccinations is also common, its pathophysiology being unclear. People with primary headache disorders experience headache in the acute phase of COVID-19 and after vaccination more commonly than the general population. Pandemic measures, forcing lifestyle changes, seemed to have had a positive impact on migraine, and changes in headache care (telemedicine) have been effectively introduced.

CONCLUSIONS

The ongoing COVID-19 pandemic is a global challenge, having an impact on the development of secondary headaches, both in people with or without primary headaches. This has created opportunities to better understand and treat headache and to potentiate strategies to manage patients and ensure care.

Comorbidity or combination - more evidence for cluster-migraine?

BACKGROUND

While migraine and cluster headache share some clinical features and therapies, they differ considerably in the frequency and duration of the headache, as well as the inter-attack, or inter-bout, pathophysiology. Neither is fully understood, with their shared pathways being of interest.

FINDINGS

Five patients for whom it was difficult to distinguish migraine from cluster headache are presented. They had aspects of their phenotypes, which could be attributed to both disorders. Each patient was thoroughly examined, excluding secondary causes of headache, and had been treated with a number of medicines.

CONCLUSION

A correct diagnosis is key to the appropriate treatment approach. Especially, if treatment is not successful for the suspected headache type, and enlargement of the diagnostic and therapeutic range, respectively, should be evaluated. Whether in such settings there is shared or different pathophysiology can only be speculated upon.

Biomarkers of Migraine and Cluster Headache: Differences and Similarities

OBJECTIVE

This study was undertaken to identify magnetic resonance imaging (MRI) biomarkers that differentiate migraine from cluster headache patients and imaging features that are shared.

METHODS

Clinical, functional, and structural MRI data were obtained from 20 migraineurs, 20 cluster headache patients, and 15 healthy controls. Support vector machine algorithms and a stepwise removal process were used to discriminate headache patients from controls, and subgroups of patients. Regional between-group differences and association between imaging features and patients' clinical characteristics were also investigated.

RESULTS

The accuracy for classifying headache patients from controls was 80%. The classification accuracy for discrimination between migraine and controls was 89%, and for cluster headache and controls it was 98%. For distinguishing cluster headache from migraine patients, the MRI classifier yielded an accuracy of 78%, whereas MRI-clinical combined classification model achieved an accuracy of 99%. Bilateral hypothalamic and periaqueductal gray (PAG) functional networks were the most important MRI features in classifying migraine and cluster headache patients from controls. The left thalamic network was the most discriminative MRI feature in classifying migraine from cluster headache patients. Compared to migraine, cluster headache patients showed decreased functional interaction between the left thalamus and cortical areas mediating interoception and sensory integration. The presence of restlessness was the most important clinical feature in discriminating the two groups of patients.

INTERPRETATION

Functional biomarkers, including the hypothalamic and PAG networks, are shared by migraine and cluster headache patients. The thalamocortical pathway may be the neural substrate that differentiates migraine from cluster headache attacks with their distinct clinical features. ANN NEUROL 2023.

Effects of eptinezumab on self-reported work productivity in adults with migraine and prior preventive treatment failure in the randomized, double-blind, placebo-controlled DELIVER study

BACKGROUND

The multinational phase 3b DELIVER trial was designed to evaluate the efficacy and safety of eptinezumab for migraine prevention in patients with prior preventive treatment failures across 17 countries. In the placebo-controlled portion, eptinezumab relative to placebo demonstrated greater reductions in migraine and headache frequency, migraine and headache severity, and acute medication use. The objective of this report is to describe the effects of eptinezumab on self-reported work productivity in the placebo-controlled portion of DELIVER.

METHODS

Adults 18-75 years of age with migraine and documented evidence of 2 to 4 prior preventive treatment failures in the past 10 years were randomized to receive eptinezumab 100 mg, 300 mg, or placebo intravenously (IV) every 12 weeks. The Work Productivity and Activity Impairment questionnaire specific to migraine (WPAI:M), which comprises 6 items (4 of which are completed by currently employed patients only), was administered every 4 weeks. Changes from baseline in subscores (absenteeism, presenteeism, work productivity loss, and activity impairment) were calculated based on item responses. A mixed model for repeated measures was used to analyze changes from baseline in WPAI:M subscores.

RESULTS

A total of 890 adults (mean age, 43.8 years) were included in the full analysis set (eptinezumab 100 mg, n = 299; eptinezumab 300 mg, n = 293; placebo, n = 298). Mean WPAI:M subscores at baseline indicated a negative impact of migraine attacks on work productivity and ability to complete normal daily activities. Eptinezumab improved WPAI:M subscores more than placebo at all assessment points throughout the study. Mean changes from baseline in self-reported work productivity loss were -19.5, -24.0, and -9.7 at Week 12; and -22.6, -20.2, and -7.2 at Week 24 (all P < 0.001 vs placebo) for eptinezumab 100 mg, eptinezumab 300 mg, and placebo, respectively. Mean changes from baseline in activity impairment were -21.3, -23.8, and -11.2 at Week 12; and -24.7, -22.6, and -10.1 at Week 24 (all P < 0.0001 vs placebo). Similarly, mean improvements in absenteeism and presenteeism were greater in the eptinezumab groups than in the groups receiving placebo at all timepoints (P < 0.05).

CONCLUSION

In adults with migraine and prior preventive treatment failure, eptinezumab 100 mg and 300 mg IV every 12 weeks improved absenteeism, presenteeism, work productivity loss, and activity impairment more than placebo.

TRIAL REGISTRATION

ClinicalTrials.gov (Identifier: NCT04418765 ); EudraCT (Identifier: 2019-004497-25) ( https://www.clinicaltrialsregister.eu/ctr-search/trial/2019-004497-25/PL ). Eptinezumab improves self-reported work productivity in patients with migraine and prior preventive treatment failures.

Pharmacological modulation of ventral tegmental area neurons elicits changes in trigeminovascular sensory processing and is accompanied by glycemic changes: Implications for migraine

BACKGROUND

Imaging migraine premonitory studies show increased midbrain activation consistent with the ventral tegmental area, an area involved in pain modulation and hedonic feeding. We investigated ventral tegmental area pharmacological modulation effects on trigeminovascular processing and consequent glycemic levels, which could be involved in appetite changes in susceptible migraine patients.

METHODS

Serotonin and pituitary adenylate cyclase-activating polypeptide receptors immunohistochemistry was performed in ventral tegmental area parabrachial pigmented nucleus of male Sprague Dawley rats. In vivo trigeminocervical complex neuronal responses to dura mater nociceptive electrical stimulation, and facial mechanical stimulation of the ophthalmic dermatome were recorded. Changes in trigeminocervical complex responses following ventral tegmental area parabrachial pigmented nucleus microinjection of glutamate, bicuculline, naratriptan, pituitary adenylate cyclase-activating polypeptide-38 and quinpirole were measured, and blood glucose levels assessed pre- and post-microinjection.

RESULTS

Glutamatergic stimulation of ventral tegmental area parabrachial pigmented nucleus neurons reduced nociceptive and spontaneous trigeminocervical complex neuronal firing. Naratriptan, pituitary adenylate cyclase-activating polypeptide-38 and quinpirole inhibited trigeminovascular spontaneous activity, and trigeminocervical complex neuronal responses to dural-evoked electrical and mechanical noxious stimulation. Trigeminovascular sensory processing through modulation of the ventral tegmental area parabrachial pigmented nucleus resulted in reduced circulating glucose levels.

CONCLUSION

Pharmacological modulation of ventral tegmental area parabrachial pigmented nucleus neurons elicits changes in trigeminovascular sensory processing. The interplay between ventral tegmental area parabrachial pigmented nucleus activity and the sensory processing by the trigeminovascular system may be relevant to understand associated sensory and homeostatic symptoms in susceptible migraine patients.

Pathophysiology and Therapy of Associated Features of Migraine

Migraine is a complex and debilitating disorder that is broadly recognised by its characteristic headache. However, given the wide array of clinical presentations in migraineurs, the headache might not represent the main troublesome symptom and it can even go unnoticed. Understanding migraines exclusively as a pain process is simplistic and certainly hinders management. We describe the mechanisms behind some of the most disabling associated symptoms of migraine, including the relationship between the central and peripheral processes that take part in nausea, osmophobia, phonophobia, vertigo and allodynia. The rationale for the efficacy of the current therapeutic arsenal is also depicted in this article. The associated symptoms to migraine, apart from the painful component, are frequent, under-recognised and can be more deleterious than the headache itself. The clinical anamnesis of a headache patient should enquire about the associated symptoms, and treatment should be considered and individualised. Acknowledging the associated symptoms as a fundamental part of migraine has permitted a deeper and more coherent comprehension of the pathophysiology of migraine.