Headache onset after vaccination against SARS-CoV-2: a systematic literature review and meta-analysis.

BACKGROUND: Vaccines against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) are used to reduce the risk of developing Coronavirus Disease 2019 (COVID-19). Despite the significant benefits in terms of reduced risk of hospitalization and death, different adverse events may present after vaccination: among them, headache is one of the most common, but nowadays there is no summary presentation of its incidence and no description of its main features. METHODS: We searched PubMed and EMBASE covering the period between January 1st 2020 and August 6th, 2021, looking for record in English and with an abstract and using three main search terms (with specific variations): COVID-19/SARS-CoV-2; Vaccination; headache/adverse events. We selected manuscript including information on subjects developing headache after injection, and such information had to be derived from a structured form (i.e. no free reporting). Pooled estimates and 95% confidence intervals were calculated. Analyses were carried out by vaccine vs. placebo, by first vs. second dose, and by mRNA-based vs. "traditional" vaccines; finally, we addressed the impact of age and gender on post-vaccine headache onset. RESULTS: Out of 9338 records, 84 papers were included in the review, accounting for 1.57 million participants, 94% of whom received BNT162b2 or ChAdOx1. Headache was generally the third most common AE: it was detected in 22% (95% CI 18-27%) of subjects after the first dose of vaccine and in 29% (95% CI 23-35%) after the second, with an extreme heterogeneity. Those receiving placebo reported headache in 10-12% of cases. No differences were detected across different vaccines or by mRNA-based vs. "traditional" ones. None of the studies reported information on headache features. A lower prevalence of headache after the first injection of BNT162b2 among older participants was shown. CONCLUSIONS: Our results show that vaccines are associated to a two-fold risk of developing headache within 7 days from injection, and the lack of difference between vaccine types enable to hypothesize that headache is secondary to systemic immunological reaction than to a vaccine-type specific reaction. Some descriptions report onset within the first 24 h and that in around one-third of the cases, headache has migraine-like features with pulsating quality, phono and photophobia; in 40-60% of the cases aggravation with activity is observed. The majority of patients used some medication to treat headache, the one perceived as the most effective being acetylsalicylic acid.

Functional connectivity changes in complex migraine aura: beyond the visual network.

BACKGROUND AND PURPOSE: Although the majority of migraine with aura (MwA) patients experience simple visual aura, a discrete percentage also report somatosensory, dysphasic or motor symptoms (the so-called complex auras). The wide aura clinical spectrum led to an investigation of whether the heterogeneity of the aura phenomenon could be produced by different neural correlates, suggesting an increased visual cortical excitability in complex MwA. The aim was to explore whether complex MwA patients are characterized by more pronounced connectivity changes of the visual network and whether functional abnormalities may extend beyond the visual network encompassing also the sensorimotor network in complex MwA patients compared to simple visual MwA patients. METHODS: By using a resting-state functional magnetic resonance imaging approach, the resting-state functional connectivity (RS-Fc) of both visual and sensorimotor networks in 20 complex MwA patients was compared with 20 simple visual MwA patients and 20 migraine without aura patients. RESULTS: Complex MwA patients showed a significantly higher RS-Fc of the left lingual gyrus, within the visual network, and of the right anterior insula, within the sensorimotor network, compared to both simple visual MwA and migraine without aura patients (p < 0.001). The abnormal right anterior insula RS-Fc was able to discriminate complex MwA patients from simple aura MwA patients as demonstrated by logistic regression analysis (area under the curve 0.83). CONCLUSION: Our findings suggest that higher extrastriate RS-Fc might promote cortical spreading depression onset representing the neural correlate of simple visual aura that can propagate to sensorimotor regions if an increased insula RS-Fc coexists, leading to complex aura phenotypes.

Disconnectome of the migraine brain: a "connectopathy" model.

BACKGROUND: In the past decades a plethora of studies has been conducted to explore resting-state functional connectivity (RS-FC) of the brain networks in migraine with conflicting results probably due to the variability and susceptibility of signal fluctuations across the course of RS-FC scan. On the other hand, the structural substrates enabling the functional communications among the brain connectome, characterized by higher stability and reproducibility, have not been widely investigated in migraine by means of graph analysis approach. We hypothesize a rearrangement of the brain connectome with an increase of both strength and density of connections between cortical areas specifically involved in pain perception, processing and modulation in migraine patients. Moreover, such connectome rearrangement, inducing an imbalance between the competing parameters of network efficiency and segregation, may underpin a mismatch between energy resources and demand representing the neuronal correlate of the energetically dysfunctional migraine brain. METHODS: We investigated, using diffusion-weighted MRI imaging tractography-based graph analysis, the graph-topological indices of the brain "connectome", a set of grey matter regions (nodes) structurally connected by white matter paths (edges) in 94 patients with migraine without aura compared to 91 healthy controls. RESULTS: We observed in migraine patients compared to healthy controls: i) higher local and global network efficiency (p < 0.001) and ii) higher local and global clustering coefficient (p < 0.001). Moreover, we found changes in the hubs topology in migraine patients with: i) posterior cingulate cortex and inferior parietal lobule (encompassing the so-called neurolimbic-pain network) assuming the hub role and ii) fronto-orbital cortex, involved in emotional aspects, and visual areas, involved in migraine pathophysiology, losing the hub role. Finally, we found higher connection (edges) probability between cortical nodes involved in pain perception and modulation as well as in cognitive and affective attribution of pain experiences, in migraine patients when compared to healthy controls (p < 0.001). No correlations were found between imaging and clinical parameters of disease severity. CONCLUSION: The imbalance between the need of investing resources to promote network efficiency and the need of minimizing the metabolic cost of wiring probably represents the mechanism underlying migraine patients' susceptibility to triggers. Such changes in connectome topography suggest an intriguing pathophysiological model of migraine as brain "connectopathy".

Effectiveness and Safety of CGRP-mAbs in Menstrual-Related Migraine: A Real-World Experience.

INTRODUCTION: Migraine shows a significantly higher prevalence in women, especially during reproductive age when menstrual-related hormonal fluctuations represent the most common migraine trigger. Indeed, over 50% of patients report a higher occurrence of migraine attacks during the perimenstrual window. Menstrual migraine attacks are consistently referred to as more disabling, less responsive to symptomatic treatments, longer in duration, and more prone to relapse than non-menstrual migraine attacks. Evidence strongly suggests that estrogen fluctuations are involved in migraine attacks worsening during the perimenstrual window through several mechanisms directly or indirectly involving the CGRP pathway. We aimed to evaluate whether mAbs blocking CGRP-ligand or receptor (CGRP-mAbs) could represent an effective and safe preventive treatment for menstrual migraine attacks in patients with menstrual-related migraine (MRM) with previous treatment failures. METHODS: Forty patients with MRM with at least three previous treatment failures received monthly CGRP-mAbs. At the baseline and after six CGRP-mAbs administrations, patients underwent to extensive interviews to assess frequency, duration, intensity, and responsiveness to painkiller intake of migraine attacks occurring during the perimenstrual window. RESULTS: After six administrations of CGRP-mAbs we observed a reduction of median menstrual migraine frequency (from 5 to 2 days per month), pain intensity (from 8/10 to 6/10), and attacks duration (from 24 to 8 h) (p < 0.001). Nevertheless, a significant increase in the percentage of responding to migraine painkillers was observed from 42.5% at baseline to 95% at T1 (p < 0.001). CONCLUSIONS: CGRP-mAbs could represent a safe and effective preventive therapeutic strategy able to reduce the disabling burden of menstrual migraine attack frequency, duration, intensity, and significantly improve the response to painkillers. These findings could be related to and further indirectly prove the greater influence of CGRP-mediated mechanisms in the pathophysiology of menstrual migraine attacks.

Refractory migraine profile in CGRP-monoclonal antibodies scenario.

OBJECTIVE: Refractory migraine (Ref-M) represents a conundrum that headache experts have to face with. We aim to investigate whether a peculiar profile may characterize patients with Ref-M according to 2020 European Headache Federation criteria. Furthermore, to substantiate a dysfunctional dopaminergic pathway involvement in these patients, we explored the effectiveness of olanzapine. MATERIALS & METHODS: Eighty-four patients (fitting previous Ref-M criteria of the 2014) were treated with erenumab for six months. Differences between clinical and demographic features of responder (Ref-M according to 2014 criteria) and not-responder (Ref-M according to 2020 criteria) patients to CGRP-mAbs were investigated and their predictive values assessed. In fifteen patients with Ref-M not responders to CGRP-mAbs, olanzapine was administered (5 mg/die) for 3 months and frequency and pain intensity of migraine attacks were estimated. RESULTS: Patients with Ref-M not responsive to CGRP-mAbs (29/84) when compared with Ref-M responsive to CGRP-mAbs showed higher baseline frequency of migraine attacks, medication overuse and pain catastrophizing scale (PCS) scores. Logistic regression analyses showed that frequency of attacks, medication overuse and PCS score represent independent negative predictors of CGRP-mAbs response. A ≥50% reduction of headache days/month was observed after olanzapine treatment in 67% of patients with Ref-M not responsive to CGRP-mAbs. CONCLUSIONS: We outline that higher frequency of migraine attacks, medication overuse and pain catastrophizing characterize patients with Ref-M not responsive to CGRP-mAbs. In this frame, olanzapine effectiveness on frequency and pain intensity of migraine attacks supports the hypothesis that migraine refractoriness may be subtended by a prominent involvement of the dopaminergic pathway.

Additive Interaction Between Onabotulinumtoxin-A and Erenumab in Patients With Refractory Migraine.

In the last decade, notable progresses have been observed in chronic migraine preventive treatments. According to the European Headache Federation and national provisions, onabotulinumtoxin-A (BTX-A) and monoclonal antibodies acting on the pathway of calcitonin gene-related peptide (CGRP-mAbs) should not be administered in combination due to supposed superimposable mechanism of action and high costs. On the other hand, preclinical observations demonstrated that these therapeutic classes, although operating directly or indirectly on the CGRP pathway, act on different fibers. Specifically, the CGRP-mAbs prevent the activation of the Aδ-fibers, whereas BTX-A acts on C-fibers. Therefore, it can be argued that a combined therapy may provide an additive or synergistic effect on the trigeminal nociceptive pathway. In the present study, we report a case series of 10 patients with chronic migraine who experienced significant benefits with the combination of both erenumab and BTX-A compared to each therapeutic strategy alone. A reduction in frequency and intensity of headache attacks (although not statistically significant probably due to the low sample size) was observed in migraine patients treated with a combined therapy with BTX-A and erenumab compared to both BTX-A and erenumab alone. Moreover, the combined therapy with BTX-A and erenumab resulted in a statistically significant reduction in the symptomatic drug intake and in migraine-related disability probably related to a reduced necessity or also to a better responsiveness to rescue treatments. Present data suggest a remodulation of current provisions depriving patients of an effective therapeutic strategy in peculiar migraine endophenotypes.

Multidimensional assessment of the effects of erenumab in chronic migraine patients with previous unsuccessful preventive treatments: a comprehensive real-world experience.

BACKGROUND: erenumab was safe and effective in clinical trials for the prevention of migraine. However, real-life data are still lacking. Here we report the clinical experience from an Italian real-world setting using erenumab in patients with chronic migraine experiencing previous unsuccessful preventive treatments. METHODS: Seventy patients with chronic migraine and failure to ≥4 migraine preventive medication classes initially received monthly erenumab 70 mg s.c. Patients without a clinically meaningful improvement, considered as a > 30% reduction in headache days per month, after ≥3 months of therapy switched to monthly erenumab 140 mg. At the first administration and after 3 and 6 months, patients underwent extensive interviews to assess clinical parameters of disease severity and migraine-related disability and impact, and validated questionnaires to explore depression/anxiety, sleep, and quality of life (QoL). Finally, the Pain Catastrophizing Scale, Allodynia Symptom Checklist-12 and MIGraine attacks-Subjective COGnitive impairments scale (MIG-SCOG) were administered. RESULTS: 70% of patients were "responders" after the third administration of erenumab 70 mg, whereas 30% switched to erenumab 140 mg; 29% (6 pts) responded after the sixth administration. The headache-day frequency was reduced from 21.1 ± 0.7 to 11.4 ± 0.9 days after the third administration (p < 0.001) and to 8.9 ± 0.7 days after the sixth administration (p < 0.001). 53% and 70% of patients, respectively, showed a reduction of ≥50% of headache days/month after the third and the sixth administrations. Also improved were headache pain severity, migraine-related disability, and impact on daily living, QoL, pain catastrophizing and allodynia (all p < 0.001), quality of sleep, symptoms of depression or anxiety (p < 0.05) but not MIG-SCOG. There were no new adverse event signals. CONCLUSION: These real-world data support monthly erenumab 70 or 140 mg s.c. as a safe and effective preventive treatment to reduce headache frequency and severity in chronic migraine patients experiencing previous unsuccessful preventive treatments.

Erenumab Efficacy on Comorbid Cluster Headache in Patients With Migraine: A Real-World Case Series.

BACKGROUND: Monoclonal antibodies (mABs) against calcitonin gene-related peptide (CGRP) or its receptor have emerged as effective and well-tolerated preventive medications for migraine. The key role played by CGRP has been recently demonstrated also in the pathophysiology of cluster headache (CH), paving the way for studies aimed to investigate the effectiveness of mABs targeting CGRP also in CH. However, no trials have been conducted so far to test the efficacy and tolerability of erenumab as CH preventive treatment. CASE SERIES: We describe the cases of 5 patients with both migraines and CH with previous failures of preventive treatments. All patients were treated with monthly erenumab (70 or 140 mg) showing good results not only on migraine but also on CH attacks frequency and intensity. Improvements of both intensity and frequency of CH attacks occurred only after at least 3 months of treatment, with monthly erenumab 140 mg, suggesting that longer treatment and higher doses are needed in CH in comparison to migraine. DISCUSSION AND CONCLUSION: Our findings support the efficacy and tolerability of monthly erenumab 140 mg as a preventive treatment in patients suffering from both migraines without aura and CH. We speculate that erenumab could represent a low-risk alternative for CH patients (with or without comorbid migraine) who did not tolerate common CH preventatives therapies or for whom the therapies were not successful. Certainly, randomized trials are needed to confirm these observations and we hope that our data, showing a delayed therapeutic effect only with the highest dose of erenumab (140 mg/month), can be taken into account in designing future trials.

A subjective cognitive impairments scale for migraine attacks: validation of the Italian version of the MIG-SCOG.

BACKGROUND: The MIG-SCOG is a questionnaire to assess self-reported subjective cognitive symptoms during migraine attacks, consisting of 9 items evaluating executive functions and language. The aim of the study was to evaluate the psychometric properties of the Italian version of the MIG-SCOG (I-MIG-SCOG) in patients with migraine without aura. METHODS: The I-MIG-SCOG underwent 20 Italian healthy subjects to assess its comprehensibility. Reliability and divergent validity of the I-MIG-SCOG were evaluated in a sample of 153 migraines without aura patients. They also underwent Montreal Cognitive Assessment, Beck Depression Inventory and Apathy Evaluation Scale. RESULTS: The final I-MIG-SCOG was easily comprehensible. There were no missing data, no floor and ceiling effects; mean I-MIG-SCOG score was 7.54 ± 3.98; Cronbach's alpha was 0.814. The I-MIG-SCOG score correlated poorly with Montreal Cognitive Assessment, Beck Depression Inventory and Apathy Evaluation Scale. CONCLUSION: The I-MIG-SCOG should represent a reliable and valid patient-centred and disease-related instrument to identify cognitive symptoms experienced during migraine attacks and to monitor the divergent effects of symptomatic treatments on cognitive functions also in Italian migraine patients.