Hypersensitivity to CGRP as a predictive biomarker of migraine prevention with erenumab.

BACKGROUND: The present study aimed to investigate the predictive value of calcitonin gene-related peptide (CGRP)-induced migraine attacks for effectiveness to erenumab treatment in people with migraine. METHODS: In total, 139 participants with migraine underwent a single experimental day involving a 20-min infusion with CGRP. Following this, the participants entered a 24-week treatment period with erenumab. The primary endpoints were the predictive value of CGRP-induced migraine attacks on the effectiveness of erenumab, defined as ≥50% reduction in monthly migraine days, or ≥ 50% reduction in either monthly migraine or monthly headache days of moderate to severe intensity. RESULTS: Among participants with CGRP-induced migraine attacks, 60 of 99 (61%) achieved ≥50% reduction in monthly migraine days during weeks 13-24 with erenumab. Conversely, 13 of 25 (52%) where CGRP infusion did not induce a migraine achieved the same endpoint (p = 0.498). There were no significant differences between the ≥50% reduction in either monthly migraine or monthly headache days of moderate to severe intensity between CGRP-sensitive and non-sensitive participants (p = 0.625). CONCLUSIONS: Our findings suggest that the CGRP-provocation model cannot be used to predict erenumab's effectiveness. It remains uncertain whether this finding extends to other monoclonal antibodies targeting the CGRP ligand or to gepants.Trial Registration: The study was registered at ClinicalTrials.gov (NCT04592952).

Postdromal symptoms in migraine: a REFORM study.

BACKGROUND: Migraine is a multiphasic neurovascular disorder, where headache can be succeeded by postdromal symptoms. However, there are limited research on postdromal symptoms. This study aimed to investigate the proportion of individuals with migraine from a tertiary care unit reporting postdromal symptoms in adherence with the ICHD-3 definition. We also aimed to examine how the means of enquiry might influence the estimated proportions. Additionally, we explored whether any clinical features might affect the likelihood of reporting postdromal symptoms. Finally, we assessed to what extend the postdromal symptoms might impact the disease burden. METHODS: In a cross-sectional study, we enrolled adult participants diagnosed with migraine who were asked to report their postdromal symptoms (i.e., unprompted reporting). Subsequently, a 16-item list was used to further ascertain the occurrence of postdromal symptoms (i.e., prompted reporting). Clinical characteristics were obtained through a semi-structured interview. Moreover, electronic questionnaires were used to assess the disease burden, i.e., the Six-Item Headache Impact Test (HIT-6), Migraine Disability Assessment (MIDAS), and the World Health Organization Disability Assessment 2.0 (WHODAS 2.0). RESULTS: Among 631 participants with migraine, a higher proportion experienced at least one postdromal symptom when prompted (n = 509 [80.7%]) compared with unprompted reporting (n = 421 [66.7%], P < 0.001). Furthermore, the total number of postdromal symptoms experienced was greater with prompted than unprompted reporting (medians 3 [IQR 1 - 6] versus 1 [IQR 0 - 2]; P < 0.001). Furthermore, the likelihood of reporting postdromal symptoms increased with the presence of premonitory symptoms and decreased with higher number of monthly migraine days. Weak correlations were identified between the number of postdromal symptoms reported and both HIT-6 (ρ = 0.14; P < 0.001) and WHODAS scores (ρ = 0.15; P < 0.001), whilst no correlation was observed with MIDAS score (ρ = 0.08; P = 0.054). CONCLUSIONS: Postdromal symptoms are prevalent in individuals with migraine from a tertiary care unit. However, reported estimates warrant cautious interpretation as they depend on the means of enquiry, presence of premonitory symptoms, and frequency of monthly migraine days. Moreover, a weak correlation was identified between the number of postdromal symptoms and both HIT-6 and WHODAS scores, indicating only a marginal influence on the disease burden.

Clinical features of migraine with aura: a REFORM study.

BACKGROUND: About one-third of persons with migraine experience transient neurologic symptoms, referred to as aura. Despite its widespread prevalence, comprehensive clinical descriptions of migraine with aura remain sparse. Therefore, we aimed to provide an in-depth phenotypic analysis of aura symptoms and characteristics in a cross-sectional study of a large sample of adults diagnosed with migraine with aura. METHODS: Data were extracted from the baseline characteristics of participants in the Registry for Migraine (REFORM) study - a single-center, prospective, longitudinal cohort study. Participants were adults diagnosed with migraine aura, reporting ≥ 4 monthly migraine days in the preceding 3 months. Trained personnel conducted in-person semi-structured interviews, capturing details on the nature, duration, localization, and progression of individual aura symptoms. RESULTS: Of the 227 enrolled participants with migraine with aura, the mean age was 41.1 years, with a predominant female representation (n = 205 [90.3%]). Visual aura was present in 215 (94.7%) participants, somatosensory aura in 81 (35.7%), and speech and/or language aura in 31 (13.7%). A single type of aura was observed in 148 (65.2%) participants, whilst 79 (34.8%) reported multiple aura types. Most participants (n = 220 [96.9%]) described their aura symptoms as positive or gradually spreading. Headache in relation to aura was noted by 218 (96.0%) participants, with 177 (80.8%) stating that the onset of aura symptoms preceded the onset of headache. CONCLUSIONS: This study offers a detailed clinical depiction of persons with migraine with aura, who were predominantly enrolled from a tertiary care unit. The findings highlight potential gaps in the available literature on migraine with aura and should bolster clinicians' acumen in diagnosing migraine with aura in clinical settings.

What proportion of people with migraine report postdromal symptoms? A systematic review and meta-analysis of observational studies.

BACKGROUND: Postdromal symptoms, following headache resolution, are said to constitute a distinct phase of the migraine attack. We question the evidence for this, with regard both to the nature of such symptoms and to how often they are reported to occur. METHODS: We searched the Pubmed and Embase databases for relevant articles from their inception until 25 May 2023. We included observational studies recording the proportions of participants with migraine reporting one or more postdromal symptoms or specific individual symptoms. Two reviewers independently screened studies for relevance (agreeing on those to be included), extracted data and assessed risk of bias. Data were analyzed using random-effects meta-analysis to establish the proportions of those with migraine reporting one or more postdromal symptoms, whether among the general population or patients in clinic-based samples. RESULTS: Large majorities of participants in either case reported postdromal symptoms: 97% in the only population-based study, and a mean of 86% (95% CI: 71-94%) in four clinic-based studies. The most commonly reported specific symptoms were fatigue (52%; 95% CI: 44-60%), concentration difficulties (35%; 95% CI: 14-65%) and mood changes (29%; 95% CI: 9-64%), none of these being clearly described. These estimates could not be considered reliable: they were subject to substantial study heterogeneity, none of the studies applied International Classification of Headache Disorders definitions of postdromal symptoms, and all had high risk of bias. CONCLUSION: Postdromal symptoms in migraine appear to be very commonly reported, but the data are unreliable with regard both to their nature and to how often they occur. Further studies are needed to conclude that they constitute a distinct phase of migraine.

Epidemiology and clinical features of hypnic headache: A systematic review and meta-analysis.

BACKGROUND: Hypnic headache is a neurological disorder characterized by recurrent headache attacks that occur exclusively during sleep, leading to awakening. Synthesizing the available epidemiological data might inform clinical decision-making. METHODS: We searched PubMed and Embase for observational studies on hypnic headache published between 1 May 2004, and 22 December 2022. Two investigators independently screened titles, abstracts, and full-text articles. We performed a random-effects meta-analysis with meta-regression to estimate the prevalence of hypnic headache and its clinical features based on epidemiologic data from population-based and clinic-based studies. RESULTS: Fourteen studies, one population-based and 13 clinic-based, met our eligibility criteria. The population-based study did not identify any people with hypnic headache. From 11 clinic-based studies, the pooled relative frequency of hypnic headache was 0.21% (95%CI, 0.13 to 0.35%; I2 = 87%) in adult patients evaluated for headache. The pooled mean age of onset was 60.5 years, with a slight female predisposition. Hypnic headache was typically bilateral (71%), pressing (73%), of moderate (38%) or severe (44%) pain intensity, and lasted about 115 minutes per attack. CONCLUSIONS: Our data should be cautiously interpreted due to between-study heterogeneity. The identified clinical presentation of hypnic headache can guide clinical diagnosis, in addition to the International Classification of Headache Disorders.

Prevalence and clinical features of hemicrania continua in clinic-based studies: A systematic review and meta-analysis.

OBJECTIVE: To estimate the relative frequencies of hemicrania continua and its clinical features in adult patients who were evaluated for headache in a clinic-based setting. METHODS: PubMed and Embase were searched for observational, clinic-based studies published between 1 January 2004 and 1 February 2022, that reported on the relative frequencies of hemicrania continua and its clinical features. Two independent investigators (HMA and SA-K) screened titles, abstracts, and full text-articles. A random-effects meta-analysis was conducted to estimate pooled relative frequencies of hemicrania continua and its clinical features across clinic-based studies. RESULTS: Eleven clinic-based studies were deemed eligible for inclusion. Of these, eight studies reported on the relative frequency of hemicrania continua among adult patients (n = 9854) who were evaluated for headache in a tertiary care unit. The pooled relative frequency of hemicrania continua was found to be 1.8% (95% CI; 1.0-3.3). Considerable heterogeneity was noted across studies (I2 = 89.8%). The three most common symptoms associated with hemicrania continua were lacrimation (72.3%), conjunctival injection (69.8%), and restlessness/agitation (60.2%). CONCLUSION: The findings of this meta-analysis suggest that there is limited epidemiologic data on the relative frequencies of hemicrania continua and its clinical features. Standardized data acquisition and reporting are needed to estimate prevalence rates more accurately and to better understand epidemiologic patterns. This, in turn, should increase awareness of the impact that hemicrania continua has in clinical practice.

An exploratory analysis of clinical and sociodemographic factors in CGRP-induced migraine attacks: A REFORM study.

OBJECTIVE: To investigate whether clinical and sociodemographic factors are associated with calcitonin gene-related peptide (CGRP) induced migraine attacks. METHODS: A total of 139 participants with migraine received a 20-minute intravenous infusion of CGRP (1.5 µg/min) on a single experiment day. The incidence of CGRP-induced migraine attacks was recorded using a headache diary during the 12-hour observational period post-infusion. Univariable and multivariable regression analyses were conducted to examine potential predictors' relationship with CGRP-induced migraine attacks. RESULTS: CGRP-induced migraine attacks were reported in 110 (79%) of 139 participants. Univariable analysis revealed that participants with cutaneous allodynia had higher odds of developing CGRP-induced migraine attacks, compared with those without allodynia (OR, 2.97, 95% CI, 1.28 to 7.43). The subsequent multivariable analysis confirmed this association (OR, 3.26, 95% CI, 1.32 to 8.69) and also found that participants with migraine with aura had lower odds of developing CGRP-induced migraine attacks (OR, 0.32, 95% CI, 0.12 to 0.84). CONCLUSION: Our results suggest that cutaneous allodynia and aura play a role in CGRP-induced migraine attacks, while other clinical and sociodemographic factors do not seem to have any noticeable impact. This indicates that the CGRP provocation model is robust, as the CGRP hypersensitivity remained unaffected despite differences among a heterogeneous migraine population.Trial Registration: ClinicalTrials.gov Identifier: NCT04592952.

Hemicrania Continua: An Update.

PURPOSE OF REVIEW: Hemicrania Continua (HC) is a rare and disabling primary headache disorder that is characterized by persistent, unilateral headache with ipsilateral, cranial autonomic symptoms and restlessness or agitation. The diagnosis requires patients to experience an absolute response to therapeutic doses of indomethacin. RECENT FINDINGS: HC is diagnosed in in about 1.8% of adult patients who were evaluated for headache in tertiary care services, albeit this estimate should be interpreted with caution. The most prevalent accompanying symptoms appear to be lacrimation, conjunctival injection and restlessness or agitation. However, the available literature is limited by methodologic issues, and the current diagnostic criteria lack clarity on what defines absolute response to indomethacin. More rigorous studies are thus needed to improve our understanding of HC which, in turn, will facilitate better disease management in clinical practice. Here, we provide a comprehensive overview of HC, including its epidemiology, clinical presentation, diagnostic evaluation, and management.

Calcitonin gene-related peptide causes migraine aura.

BACKGROUND: Although the involvement of calcitonin gene-related peptide (CGRP) in migraines is well-established, its specific role in investigating the aura phase, which often precedes the headache, remains largely unexplored. This study aims to instigate CGRP's potential in triggering aura, thus establishing its role in the early stages of migraine. METHODS: In this open-label, non-randomized, single-arm trial, 34 participants with migraine with aura received continuous intravenous infusion of CGRP (1.5 µg/min) over 20 min on a single experimental day. Participants were required to be free of headache and report no use of acute medications 24 h before infusion start. The primary endpoint was the incidence of migraine aura during the 12-hour observational period after the start of infusion. RESULTS: Thirteen (38%) of 34 participants developed migraine aura after CGRP infusion. In addition, 24 (71%) of 34 participants developed migraine headache following CGRP infusion. CONCLUSIONS: Our findings suggest that CGRP could play an important role in the early phases of a migraine attack, including during the aura phase. These insights offer a new perspective on the pathogenesis of migraines with aura. They underscore the need for additional research to further explore the role of CGRP in these initial stages of a migraine attack, and potentially inform future development of therapeutic interventions. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT04592952.

The Registry for Migraine (REFORM) study: methodology, demographics, and baseline clinical characteristics.

BACKGROUND: Erenumab has demonstrated effectiveness for prevention of migraine attacks, but the treatment is costly, and a considerable proportion of patients do not respond to it. The Registry for Migraine study (REFORM) was initiated to discover biomarkers that can predict response to erenumab in patients with migraine. The specific objective was to investigate differences in erenumab efficacy based on clinical information, blood-based biomarkers, structural and functional magnetic resonance imaging (MRI), and response to intravenous infusion of calcitonin gene-related peptide (CGRP). In this first report of the REFORM study, we provide a comprehensive description of the study methodology, and present the baseline characteristics of the study population. METHODS: The REFORM study was a single-center, prospective, longitudinal cohort study in adults with migraine who were scheduled to receive preventive treatment with erenumab as part of a separate, open-label, single-arm phase IV trial. The study included four periods: a 2-week screening period (Weeks -6 to -5), 4-week baseline period (Week -4 to Day 1), 24-week treatment period (Day 1 to Week 24), and a 24-week follow-up period without treatment (Week 25 to Week 48). Demographic and clinical characteristics were recorded using a semi-structured interview, whilst outcome data were obtained using a headache diary, patient-reported outcomes, blood sampling, brain MRI, and responsiveness to intravenous infusion of CGRP. RESULTS: The study enrolled 751 participants, with a mean age ± SD of 43.8 ± 12.2 years, of which 88.8% (n = 667) were female. At enrollment, 64.7% (n = 486) were diagnosed with chronic migraine, and 30.2% (n = 227) had history of aura. The mean monthly migraine days (MMDs) was 14.5 ± 7.0. Concomitant preventive medications were used by 48.5% (n = 364) of the participants, and 39.9% (n = 300) had failed ≥ 4 preventive medications. CONCLUSION: The REFORM study enrolled a population with a high migraine burden and frequent use of concomitant medications. The baseline characteristics were representative of patients with migraine in specialized headache clinics. Future publications will report the results of the investigations presented in this article. TRIAL REGISTRATION: The study and sub-studies were registered on ClinicalTrials.gov (NCT04592952; NCT04603976; and NCT04674020).

Functional MRI in migraine.

PURPOSE OF REVIEW: The underlying mechanisms of migraine are complex and heterogenous. Advances in neuroimaging techniques during the past few decades have contributed to our understanding of migraine pathophysiology. Brain function in migraine patients has been widely explored using functional MRI (fMRI). This review will highlight the major fMRI findings that characterize the different phases of migraine. RECENT FINDINGS: The migraine attack starts with hypothalamic hyperexcitability and early reorganization of the common ascending pain and central trigeminovascular pathways. Moreover, the visual cortex becomes hyperexcitable during the aura phase. During the headache phase, further disruptions of the pontine, thalamic, sensorimotor and visual networks occur, although the hypothalamic activity and connectivity normalizes. The visual cortex remains hyperexcitable during the postdromal phase. Asymptomatic migraine patients can also experience functional alternations of pain and visual processing brain areas. At present, the heterogeneity of the asymptomatic phase and fMRI findings make it difficult to find common denominator. SUMMARY: fMRI studies have captured functional brain changes associated with migraine phases, leading to an improvement of our understanding of migraine pathophysiology. Further MRI studies are needed to disclose whether the migraine attack is triggered by intrinsic brain dysfunction or external factors.

Provoked versus spontaneous migraine attacks: pathophysiological similarities and differences.

BACKGROUND: The onset and duration of spontaneous migraine attacks are most often difficult to predict which, in turn, makes it challenging to study the neurobiologic underpinnings of the disease in a controlled experimental setting. To address this challenge, human provocation studies can be used to identify signaling molecules (e.g. calcitonin gene-related peptide, pituitary adenylate cyclase-activating polypeptide) that, upon intravenous or oral administration, induce migraine attacks in people with migraine and mild or no headache in healthy volunteers. This approach has proven to be valid for decades and plays an integral role in mapping signaling pathways underlying migraine pathogenesis and identification of novel drug targets. However, the question arises as to whether the pathogenic mechanisms of provoked and spontaneous migraine attacks differ. In this paper, we provide an opinionated discussion on the similarities and differences between provoked and spontaneous attacks based on the current understanding of migraine pathogenesis. METHODS: The PubMed database was searched in July 2022 for original research articles on human provocation studies that included participants with migraine. The reference lists of originally identified articles were also searched and we selected those we judged relevant. DISCUSSION: People with migraine describe that provoked attacks resemble their spontaneous attacks and can be treated with their usual rescue medication. From a neurobiologic standpoint, provoked and spontaneous migraine attacks appear to be similar, except for the source of migraine-inducing substances (exogenous vs. endogenous source). In addition, provoked attacks can likely not be used to study the events that precede the release of migraine-inducing signaling molecules from sensory afferents and/or parasympathetic efferents during spontaneous attacks.

Imaging the inflammatory phenotype in migraine.

Several preclinical and clinical lines of evidence suggest a role of neuroinflammation in migraine. Neuroimaging offers the possibility to investigate and localize neuroinflammation in vivo in patients with migraine, and to characterize specific inflammatory constituents, such as vascular permeability, and macrophage or microglia activity. Despite all imaging data accumulated on neuroinflammation across the past three decades, an overview of the imaging evidence of neuroinflammation in migraine is still missing.We conducted a systematic review in the Pubmed and Embase databases to evaluate existing imaging data on inflammation in migraine, and to identify gaps in the literature. We included 20 studies investigating migraine without aura (N = 4), migraine with aura (N = 8), both migraine with and without aura (N = 3), or hemiplegic migraine (N = 5).In migraine without aura, macrophage activation was not evident. In migraine with aura, imaging evidence suggested microglial and parameningeal inflammatory activity. Increased vascular permeability was mostly found in hemiplegic migraine, and was atypical in migraine with and without aura. Based on the weight of existing and emerging data, we show that most studies have concentrated on demonstrating increased vascular permeability as a marker of neuroinflammation, with tools that may not have been optimal. In the future, novel, more sensitive techniques, as well as imaging tracers delineating specific inflammatory pathways may further bridge the gap between preclinical and clinical findings.

Premonitory symptoms in migraine: a systematic review and meta-analysis of observational studies reporting prevalence or relative frequency.

BACKGROUND: Observational studies on the prevalence of premonitory symptoms in people with migraine, preceding the headache pain (or aura) phase, have shown conflicting results. We conducted a systematic review and meta-analysis to estimate the prevalence, and relative frequency among clinic populations, of premonitory symptoms in people with migraine, overall and of the multifarious individual symptoms, and to review the methodologies used to assess them. METHODS: We searched PubMed and Embase for studies published from database inception until 31st of May 2022. Two investigators independently screened titles, abstracts, and full texts. We retrieved observational studies that reported the prevalence/relative frequency of one or more premonitory symptoms in people with migraine. Two investigators independently extracted data and assessed risk of bias. Results were pooled using random-effects meta-analysis. Our main outcomes were the percentage of people with migraine who experienced at least one premonitory symptom and the percentages who experienced different individual premonitory symptoms. To describe our outcomes, we used the terms prevalence for data from population-based samples and relative frequency for data from clinic-based samples. We also descriptively and critically assessed the methodologies used to assess these symptoms. RESULTS: The pooled estimated prevalence in population-based studies of at least one premonitory symptom was 29% (95% CI: 8-63; I2 99%) and the corresponding pooled estimated relative frequency in clinic-based studies was 66% (95% CI: 45-82; I2 99%). The data from clinic-based studies only supported meta-analysis of 11 of 96 individual symptoms, with relative frequency estimates ranging from 11 to 49%. Risk of bias was determined as high in 20 studies, moderate in seven, and low in two. CONCLUSIONS: The substantial between-study heterogeneity demands cautious interpretation of our estimates. Studies showed wide methodological variations, and many lacked rigor. Overall, the evidence was insufficient to support reliable prevalence estimation or characterization of premonitory symptoms. More data are needed, of better quality, to confirm the existence of a distinctive premonitory phase of migraine, and its features. Methodological guidelines based on expert consensus are a prerequisite.

Improved Osteoarthritis during Erenumab Treatment for Migraine: A Case Report.

Antibodies blocking the calcitonin gene-related peptide have revolutionized episodic and chronic migraine treatment. However, their applicability to non-cephalic pain conditions, such as osteoarthritis, is yet unknown. Osteoarthritis remains a clinical challenge, associated with high disability and limited treatment options. Like migraine, neuropeptides including calcitonin gene-related peptides are involved in its pathophysiology. We present the first case of a patient: a 73-year-old female with osteoarthritis who received monthly treatment for her chronic migraine with 140 mg subcutaneous erenumab, a monoclonal antibody against the receptor of calcitonin gene-related peptide. Though the migraine was unresponsive, the patient's arthritic symptoms improved drastically during treatment period with erenumab; daily pain decreased from VAS 7 to 2, and walking distance doubled from 1,000 m to 2,000 m. The arthritic symptoms relapsed after discontinuation of erenumab. Erenumab could potentially have beneficial effects on symptoms of osteoarthritis. Future studies investigating these effects are warranted.

Arterial responses to infusion of glucagon-like peptide-1 in humans: A randomized trial study.

Glucagon-like-peptide-1 (GLP-1) is an incretin hormone implicated in several metabolic and neurological disorders. GLP-1 induces vasodilation and increases blood flow in the peripheral circulation. Whether GLP-1 alters cerebral hemodynamics in humans is yet to be elucidated. In a crossover, double-blind, placebo-controlled, and randomized design, 21 healthy volunteers were assigned to receive intravenous GLP-1 infusion (2.5 pmol/kg/min) or placebo over 20 min on two different days separated by at least one week. We used a noninvasive, well-validated transcranial doppler (TCD) and ultrasound dermascan to reveal the effect of GLP-1 on intra- and extracerebral arteries. The mean blood flow velocity in the middle cerebral artery (VMCA), the diameter of the superficial temporal artery (STA) and radial artery (RA), and facial skin blood flow were measured. In addition, we documented headache and its associated symptoms during and after infusion. Twenty participants were included in the final analysis. We found no difference in the VMCA (P = 0.227), diameter of the STA (P = 0.096) and the RA (P = 0.221) and facial blood flow (P = 0.814) after GLP-1 compared to placebo. There were no differences in HR, SAT, EtCO2, or RF (P > 0.05) on the GLP-1 day compared to the placebo day. We found no differences in the incidence of headache after GLP-1 (n = 10) compared to placebo (n = 7) (P = 0.250). GLP-1 infusion did not affect cerebral hemodynamics and induce headache in humans. Further preclinical studies with validated methods are required to determine if intra - and extracerebral vasculature express GLP-1Rs in humans.