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BACKGROUND: In an effort to improve migraine management around the world, the International Headache Society (IHS) has here developed a list of practical recommendations for the acute pharmacological treatment of migraine. The recommendations are categorized into optimal and essential, in order to provide treatment options for all possible settings, including those with limited access to migraine medications. METHODS: An IHS steering committee developed a list of clinical questions based on practical issues in the management of migraine. A selected group of international senior and junior headache experts developed the recommendations, following expert consensus and the review of available national and international headache guidelines and guidance documents. Following the initial search, a bibliography of twenty-one national and international guidelines was created and reviewed by the working group. RESULTS: A total of seventeen questions addressing different aspects of acute migraine treatment have been outlined. For each of them we provide an optimal recommendation, to be used whenever possible, and an essential recommendation to be used when the optimal level cannot be attained. CONCLUSION: Adoption of these international recommendations will improve the quality of acute migraine treatment around the world, even where pharmacological options remain limited.
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Trastornos Migrañosos , Trastornos Migrañosos/tratamiento farmacológico , Humanos , Analgésicos/uso terapéutico , Sociedades Médicas/normasRESUMEN
BACKGROUND: Chronic migraine is a highly debilitating condition that is often difficult to manage, particularly in the presence of medication overuse headache. Drugs targeting the calcitonin gene-related peptide (CGRP), or its receptor have shown promising results in treating this disorder. METHODS: We searched Pubmed and Embase to identify randomized clinical trials and real-world studies reporting on the use of medication targeting the calcitonin gene-related peptide in patients with chronic migraine. RESULTS: A total of 270 records were identified. Nineteen studies qualified for the qualitative analysis. Most studies reported on monoclonal antibodies targeting CGRP (anti-CGRP mAbs), that overall prove to be effective in decreasing monthly migraine days by half in about 27.6-61.4% of the patients. Conversion from chronic to episodic migraine was seen in 40.88% of the cases, and 29-88% of the patients stopped medication overuse. Obesity seems to be the main negative predictor of response to anti-CGRP mAbs. There is no evidence to suggest the superiority of one anti-CGRP mAb. Despite the lack of strong evidence, the combination of anti-CGRP medication with onabotulinumtoxinA in chronic migraine is likely to bring benefits for resistant cases. Atogepant is the first gepant to demonstrate a significant decrease in monthly migraine days compared to placebo in a recent trial. Further, anti-CGRP mAb and gepants have a good safety profile. CONCLUSION: There is strong evidence from randomized trials and real-world data to suggest that drugs targeting CGRP are a safe and effective treatment for chronic migraine.
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Péptido Relacionado con Gen de Calcitonina , Trastornos Migrañosos , Humanos , Péptido Relacionado con Gen de Calcitonina/uso terapéutico , Trastornos Migrañosos/tratamiento farmacológico , Anticuerpos Monoclonales/uso terapéutico , Receptores de Péptido Relacionado con el Gen de Calcitonina , Antagonistas del Receptor Peptídico Relacionado con el Gen de la Calcitonina/farmacología , Antagonistas del Receptor Peptídico Relacionado con el Gen de la Calcitonina/uso terapéuticoRESUMEN
PURPOSE: Treatments in medicine impact individuals beyond their intended effects, due to phenomena such as the placebo and nocebo effects. The placebo effect arises from the positive expectation of a treatment being beneficial, while the nocebo effect stems from the negative expectation of a treatment causing harm. Both in real-world practice and clinical trials, treatments can lead to outcomes unrelated to their intended mechanism of action, which we categorize as placebo and nocebo responses. These responses, combined with the inherent fluctuation in a condition's natural progression, regression to the mean, and random comorbidities, make up a significant part of the therapeutic experience. Particularly in pain management, placebo and nocebo effects play a substantial role. By addressing modifiable contextual factors such as patient expectations, lifestyle choices, and the therapeutic relationship, healthcare providers can enhance the effectiveness of migraine treatments, paving the way for a more comprehensive, individualized approach to patient care. We must also consider non-modifiable factors like personal experiences, beliefs, and information from social media and the internet. CONCLUSION: This review offers a summary of our current understanding of the placebo and nocebo effects in migraine management.
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Trastornos Migrañosos , Efecto Nocebo , Humanos , Trastornos Migrañosos/tratamiento farmacológico , Efecto Placebo , Manejo del DolorRESUMEN
BACKGROUND: Headache disorders are a global public health concern affecting diverse populations. This review examines headache service organizations in low-, middle-, and high-income countries. It addresses global challenges in pharmacological headache treatment, with a focus on safety, tolerability, reproductive and child health, and outlines disparities in accessing innovative treatments worldwide. MAIN BODY: Organized headache services are essential due to the wide prevalence and varying severity of headache disorders. The tiered headache service model is globally recognized, although its implementation varies based on financial and workforce considerations. Headache burden affects well-being, causing disability, economic challenges, and work limitations, irrespective of location or income. All nations still require improved diagnosis and treatment, and the majority of countries face obstacles including limited access, awareness, economic barriers, and inadequate health policies. Provided adequate internet availability, telemedicine could help improve health equity by expanding access to headache care, since it can offer patients access to services without lengthy waiting times or extensive travel and can provide healthcare unavailable in underserved areas due to staff shortages. Numerous health disparities restrict global access to many headache medications, especially impacting individuals historically excluded from randomized controlled trials, such as those with cardiovascular and cerebrovascular conditions, as well as pregnant women. Furthermore, despite advancements in researching migraine treatments for young patients, the options for treatment remain limited. Access to headache treatment relies on factors like medication availability, approval, financial coverage, and healthcare provider expertise. Inadequate public awareness leads to neglect by policymakers and undertreatment by patients and healthcare providers. Global access discrepancies are exacerbated by the introduction of novel disease-specific medications, particularly impacting Asian, African, and Latin American nations excluded from clinical trials. While North America and Europe experience broad availability of migraine treatments, the majority of countries worldwide lack access to these therapies. CONCLUSIONS: Healthcare disparities, treatment access, and medication availability are concerning issues in headache medicine. Variations in national healthcare systems impact headache management, and costly innovative drugs are widening these gaps. Healthcare practitioners and experts should acknowledge these challenges and work towards minimizing access barriers for equitable global headache care in the future.
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Personas con Discapacidad , Equidad en Salud , Trastornos Migrañosos , Niño , Humanos , Femenino , Embarazo , Cefalea , Personal de SaludRESUMEN
BACKGROUND: The cyclical brain disorder of sensory processing accompanying migraine phases lacks an explanatory unified theory. METHODS: We searched Pubmed for non-invasive neurophysiological studies on migraine and related conditions using transcranial magnetic stimulation, electroencephalography, visual and somatosensory evoked potentials. We summarized the literature, reviewed methods, and proposed a unified theory for the pathophysiology of electrophysiological abnormalities underlying migraine recurrence. RESULTS: All electrophysiological modalities have determined specific changes in brain dynamics across the different phases of the migraine cycle. Transcranial magnetic stimulation studies show unbalanced recruitment of inhibitory and excitatory circuits, more consistently in aura, which ultimately results in a substantially distorted response to neuromodulation protocols. Electroencephalography investigations highlight a steady pattern of reduced alpha and increased slow rhythms, largely located in posterior brain regions, which tends to normalize closer to the attacks. Finally, non-painful evoked potentials suggest dysfunctions in habituation mechanisms of sensory cortices that revert during ictal phases. CONCLUSION: Electrophysiology shows dynamic and recurrent functional alterations within the brainstem-thalamus-cortex loop varies continuously and recurrently in migraineurs. Given the central role of these structures in the selection, elaboration, and learning of sensory information, these functional alterations suggest chronic, probably genetically determined dysfunctions of the synaptic short- and long-term learning mechanisms.
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Encefalopatías , Trastornos Migrañosos , Humanos , Encéfalo , Tronco Encefálico , Plasticidad NeuronalRESUMEN
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.
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Migraña con Aura , Humanos , Migraña con Aura/diagnóstico por imagen , Serotonina , Imagen por Resonancia Magnética/métodos , Encéfalo/diagnóstico por imagenRESUMEN
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-HT1F receptor agonists (ditans) and non-invasive neuromodulation, as well as providing a brief overview of new evidence for classic migraine treatments.
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Trastornos Migrañosos , Migraña con Aura , Humanos , Trastornos Migrañosos/tratamiento farmacológico , Péptido Relacionado con Gen de Calcitonina , Antagonistas del Receptor Peptídico Relacionado con el Gen de la Calcitonina/uso terapéutico , Receptores de Péptido Relacionado con el Gen de Calcitonina , Migraña con Aura/tratamiento farmacológicoRESUMEN
BACKGROUND: Several novel treatments targeting the calcitonin gene-related peptide pathway have been developed for migraine. We evaluated the efficacy of these medications, including atogepant, rimegepant, erenumab, eptinezumab, fremanezumab, and galcanezumab, for the prevention of migraine via network meta-analysis. METHODS: Databases, including MEDLINE via PubMed, EMBASE, and Cochrane central, were systematically reviewed, and all eligible phase 3 randomised controlled trials were included. RESULTS: Nineteen studies (n = 14,584 participants) were included. Studies included episodic (n = 11) and chronic (n = 4) migraine or both (n = 4). All interventions, except for eptinzumab 30 mg, significantly reduced mean monthly migraine days compared to placebo. All medications had a higher ≥50% responder rate than placebo and results were statistically significant in those with the subcutaneous or intravenous route of administrations, but not with the oral one. All medications significantly reduced mean monthly headache days, although no data for this outcome was available for rimegepant, and mean monthly acute medication days, with no data for eptinezumab. CONCLUSION: The results show that medications targeting calcitonin gene-related peptide were effective in preventing migraine compared to placebo. Considering limitations of single studies, different populations such as episodic and chronic migraine, and the absence of head-to-head trials, all novel treatments decreased mean monthly migraine and headache days, and showed higher 50%, 75% and 100% responder rates than placebo.Trial registration: PROSPERO registration: CRD42022310579.
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Péptido Relacionado con Gen de Calcitonina , Trastornos Migrañosos , Humanos , Antagonistas del Receptor Peptídico Relacionado con el Gen de la Calcitonina/uso terapéutico , Metaanálisis en Red , Trastornos Migrañosos/tratamiento farmacológico , Trastornos Migrañosos/prevención & control , Cefalea , Ensayos Clínicos Controlados Aleatorios como AsuntoRESUMEN
Objectives: Migraine is one of the most frequent clinical manifestations of hypermobile Ehlers-Danlos syndrome (hEDS). The comorbidity between these two diseases has been only partially investigated. We aimed to observe whether neurophysiological alterations described in migraineurs in visual evoked potentials (VEPs) were present in hEDS patients with migraine. Methods: We enrolled 22 hEDS patients with migraine (hEDS) and 22 non-hEDS patients with migraine (MIG), with and without aura (according to ICHD-3), as well as 22 healthy controls (HC). Repetitive pattern reversal (PR)-VEPs were recorded in basal conditions in all participants. During uninterrupted stimulation, 250 cortical responses were recorded (4,000 Hz sample rate) and divided into epochs of 300 ms after the stimulus. Cerebral responses were divided into five blocks. The habituation was calculated as the slope interpolating the amplitudes in each block, for both the N75-P100 and P100-N145 components of PR-VEP. Results: We observed a significant habituation deficit of the P100-N145 component of PR-VEP in hEDS compared to HC (p = 0.002), unexpectedly more pronounced than in MIG. We observed only a slight habituation deficit of N75-P100 in hEDS, with a slope degree that was intermediate between MIG and HC. Discussion: hEDS patients with migraine presented an interictal habituation deficit of both VEPs components like MIG. Pathophysiological aspects underlying the pathology could account for the peculiar pattern of habituation in hEDS patients with migraine characterized by a pronounced habituation deficit in the P100-N145 component and a less clear-cut habituation deficit in the N75-P100 component with respect to MIG.
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Visual snow syndrome is a neurological condition characterized by ongoing prominent phenomena described consistently as tiny dots moving across the entire visual field, often associated with complex visual symptoms. These can take the form of afterimages, entoptic phenomena, nyctalopia and light sensitivity. Although some of these symptoms can be benign, they can nonetheless become significantly impactful for many who experience them, particularly in cases that have a sudden and abrupt start. As visual snow syndrome becomes increasingly recognized in clinical practice we begin to learn about its typical presentation and underlying pathophysiology. Treatment of visual snow, however, still proves quite challenging, and efforts need to be focused on unravelling the biological mechanisms of the syndrome. This endeavour has characterized the most recent research on visual snow, mostly involving neuroimaging, neurophysiological and neurobehavioral studies aimed at understanding its underlying neural signature. Another important aspect of the syndrome, which will likely prove critical in deepening our understanding of visual snow, is represented by the intricate biological and historical connexion with migraine. This narrative review focused on visual snow syndrome will explore its clinical, pathophysiological and treatment aspects in detail.
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Trastornos Migrañosos , Humanos , Trastornos Migrañosos/diagnóstico , Trastornos Migrañosos/terapia , Trastornos Migrañosos/complicaciones , Trastornos de la Visión/etiología , Trastornos de la Visión/diagnóstico , Campos Visuales , SíndromeRESUMEN
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.
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Trastornos Migrañosos , Adulto , Humanos , Metaanálisis en Red , Método Doble Ciego , Trastornos Migrañosos/tratamiento farmacológico , Trastornos Migrañosos/diagnóstico , Resultado del TratamientoRESUMEN
BACKGROUND: Direct comparisons of the tolerability and safety of migraine preventive treatments targeting the calcitonin gene-related peptide pathway are lacking. This study aimed to compare the safety and tolerability of anti-calcitonin gene-related peptide monoclonal antibodies and gepants in migraine prevention. METHODS: A network meta-analysis of phase 3 randomized controlled trials assessing the safety and tolerability of anti-calcitonin gene-related peptide monoclonal antibodies (erenumab, eptinezumab, fremanezumab, or galcanezumab) and gepants (atogepant, rimegepant) in migraine prevention was performed. Primary outcomes were treatment-emergent adverse events and serious adverse events. Secondary outcomes included any adverse events, adverse events leading to treatment discontinuation and individual adverse events. RESULTS: We included 19 randomized controlled trials, comprising 14,584 patients. Atogepant 120 mg (OR 2.22, 95% CI [1.26, 3.91]) and galcanezumab 240 mg (OR 1.63, 95% CI [1.33, 2.00]) showed the largest odds of treatment-emergent adverse events compared to placebo. While eptinezumab 30 mg had greater odds of adverse events leading to treatment discontinuation (OR 2.62, 95% CI [1.03,6.66]). No significant differences in serious adverse events were found between active treatments and placebo. Eptinezumab was associated with the lowest odds of treatment-emergent adverse events and serious adverse events compared to placebo, whereas erenumab was associated with the lowest odds of any adverse events and quarterly fremanezumab with the lowest odds of treatment discontinuation due to adverse events. CONCLUSION: Monoclonal antibodies targeting the calcitonin gene-related peptide pathway and gepants are a safe and well tolerated option for migraine prevention.
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Péptido Relacionado con Gen de Calcitonina , Trastornos Migrañosos , Humanos , Péptido Relacionado con Gen de Calcitonina/metabolismo , Antagonistas del Receptor Peptídico Relacionado con el Gen de la Calcitonina/efectos adversos , Metaanálisis en Red , Trastornos Migrañosos/tratamiento farmacológico , Trastornos Migrañosos/prevención & control , Trastornos Migrañosos/inducido químicamente , Anticuerpos Monoclonales/efectos adversosRESUMEN
Migraine is a severe and common primary headache disorder, characterized by pain as well as a plethora of non-painful symptoms. Among these, visual phenomena have long been known to be associated with migraine, to the point where they can constitute a hallmark of the disease itself. In this review we focus on two key visual disorders that are directly or indirectly connected to migraine: visual aura and visual snow syndrome (VSS). Visual aura is characterized by the transient presence of positive and negative visual symptoms, before, during or outside of a migraine attack. VSS is a novel stand-alone phenomenon which has been shown to be comorbid with migraine. We discuss key clinical features of the two disorders, including pathophysiological mechanisms, their differential diagnoses and best treatment practices. Our aim is to provide an aid for clinicians and researchers in recognizing these common visual phenomena, which can even appear simultaneously in patients with an underlying migraine biology.
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Visual snow syndrome is characterized by a continuous visual disturbance resembling a badly tuned analogue television and additional visual and non-visual symptoms causing significant disability. The natural course of visual snow syndrome has not hitherto been studied. In this prospective longitudinal study, 78 patients with the diagnosis of visual snow syndrome made in 2011 were re-contacted in 2019 to assess symptom evolution using a semi-structured questionnaire. Forty patients (51% of 78) were interviewed after 84 ± 5 months (mean ± SD). In all patients, symptoms had persisted. Visual snow itself was less frequently rated as the most disturbing symptom (72 versus 42%, P = 0.007), whereas a higher proportion of patients suffered primarily from entopic phenomena (2 versus 17%, P = 0.024). New treatment was commenced in 14 (35%) patients, of whom in seven, visual snow syndrome was ameliorated somewhat. Three (7%) experienced new visual migraine aura without headache, and one (2%) had new migraine headache. There were no differences in the levels of anxiety and depression measured by the Patient Health Questionnaire 8 and the Generalized Anxiety Disorder Scale 7. Thirty-eight patients (49%) were lost to follow-up. In visual snow syndrome, symptoms can persist over 8 years without spontaneous resolution, although visual snow itself might become less bothersome.
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OBJECTIVE: To compare the clinical phenotype of patients with chronic migraine (CM) to patients with new daily persistent headache of the chronic migraine subtype (NDPH-CM). METHODS: A study was conducted of CM (n = 257) and NDPH-CM (n = 76) from a tertiary headache center in the UK, and in the US of patients with daily CM (n = 60) and NDPH-CM (n = 22). RESULTS: From the UK cohort, the age of first headache onset was lower in CM (mean ± SD: 16 ± 12 years) than in NDPH-CM (mean ± SD: 23 ± 14 years; p < 0.001). There was a greater number of associated migrainous symptoms in CM compared to NDPH-CM (median and interquartile range: 6, 5-8 vs. 5, 4-7; p < 0.001). A family history of headache was more common in CM compared to NDPH-CM (82%, 202/248, vs. 53%, 31/59; p < 0.001). In the US cohort there were no differences. Osmophobia (B = -1.08; p = 0.002) and older age at presentation to the clinic (B = -0.06; p = 0.001) were negative predictors of NDPH-CM. CONCLUSION: NDPH-CM is relatively less migrainous than CM in the UK cohort. Family history of headache is less common in NDPH-CM, with negative predictors for NDPH-CM including osmophobia and older age of presentation to the clinic. More work is required to understand the chronic migraine phenotype of new daily persistent headache.
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Trastornos de Cefalalgia , Trastornos Migrañosos , Cefalea/diagnóstico , Cefalea/epidemiología , Cefalea/etiología , Trastornos de Cefalalgia/diagnóstico , Trastornos de Cefalalgia/epidemiología , Humanos , Trastornos Migrañosos/complicaciones , Trastornos Migrañosos/diagnóstico , Trastornos Migrañosos/epidemiología , FenotipoRESUMEN
BACKGROUND: The International Headache Society has been offering multiple award opportunities for young researchers and clinicians for many years, with the aim of supporting the development of careers in headache science and medicine. METHODS: In order to assess the outcomes of the International Headache Society award grants, a questionnaire was sent to all previous recipients, investigating a series of aspects related to their work, both during and after award completion. RESULTS: Of 44 total questionnaires sent, 36 were returned. Eighty-one percent of the recipients reported to have remained in the headache field since the award, half of them held a current academic position and over three-quarters had stayed in contact with the host institution. The totality of questionnaire responders stated that the grant had had a significantly positive impact on their careers. CONCLUSIONS: The International Headache Society grants have assisted many young researchers in building an academic and clinical career in the field of headache, throughout the years.
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Investigación Biomédica , Organización de la Financiación , Cefalea , Humanos , Sociedades MédicasRESUMEN
Visual snow syndrome is a novel neurological condition characterized by a panfield visual disturbance associated with several additional symptoms. Although it is usually a continuous and primary disorder, cases of intermittent visual snow have been described in the literature, as well as rare secondary forms. This report is the first description of a case of intermittent visual snow syndrome, which transformed into a persistent form following a posterior circulation stroke due to vertebral artery dissection. At 1 and 2 years after experiencing the acute cerebellar infarct, the patient's only neurological sequalae was visual snow. This case provides a description of how visual snow syndrome may be caused by an underlying brain disorder, and highlights the importance of the cerebellum in the pathophysiology of this relatively unknown condition. It further shows evidence of how existing predispositions might be relevant to the development of visual snow, in certain subjects and following specific circumstances.
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AIMS: Neuronal nitric oxide synthase (nNOS) is highly expressed within the cardiovascular and nervous systems. Studies in genetically modified mice suggest roles in brain blood flow regulation while dysfunctional nNOS signalling is implicated in cerebrovascular ischaemia and migraine. Previous human studies have investigated the effects of non-selective NOS inhibition but there has been no direct investigation of the role of nNOS in human cerebrovascular regulation. We hypothesized that inhibition of the tonic effects of nNOS would result in global or localized changes in cerebral blood flow (CBF), as well as changes in functional brain connectivity. METHODS AND RESULTS: We investigated the acute effects of a selective nNOS inhibitor, S-methyl-L-thiocitrulline (SMTC), on CBF and brain functional connectivity in healthy human volunteers (n = 19). We performed a randomized, placebo-controlled, crossover study with either intravenous SMTC or placebo, using magnetic resonance imaging protocols with arterial spin labelling and functional resting state neuroimaging. SMTC infusion induced an â¼4% decrease in resting global CBF [-2.3 (-0.3, -4.2) mL/100g/min, mean (95% confidence interval, CI), P = 0.02]. In a whole-brain voxel-wise factorial-design comparison of CBF maps, we identified a localized decrease in regional blood flow in the right hippocampus and parahippocampal gyrus following SMTC vs. placebo (2921 voxels; T = 7.0; x = 36; y = -32; z = -12; P < 0.001). This was accompanied by a decrease in functional connectivity to the left superior parietal lobule vs. placebo (484 voxels; T = 5.02; x = -14; y = -56; z = 74; P = 0.009). These analyses adjusted for the modest changes in mean arterial blood pressure induced by SMTC as compared to placebo [+8.7 mmHg (+1.8, +15.6), mean (95% CI), P = 0.009]. CONCLUSIONS: These data suggest a fundamental physiological role of nNOS in regulating regional CBF and functional connectivity in the human hippocampus. Our findings have relevance to the role of nNOS in the regulation of cerebral perfusion in health and disease.
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Encéfalo , Inhibidores Enzimáticos , Animales , Encéfalo/metabolismo , Estudios Cruzados , Inhibidores Enzimáticos/farmacología , Humanos , Ratones , Óxido Nítrico , Óxido Nítrico Sintasa de Tipo I/metabolismo , Perfusión , Flujo Sanguíneo RegionalRESUMEN
Nummular headache (NH) is a primary headache characterized by superficial coin-shaped pain. NUMITOR (NCT05475769) is an observational study evaluating the responder rate of preventive drugs in NH patients. The treatment response was assessed between weeks 8 and 12 compared with the baseline. Patients were included between February 2002 and October 2022. Demographic and clinical variables were assessed; treatment response was estimated by 50%, 30%, and 75% responder rates and treatment discontinuation due to inadequate tolerability. A total of 183 out of 282 patients fulfilled eligibility criteria and completed the study. Patients were aged 49.5 (standard deviation (SD): 16.8) years, and 60.7% were female. NH phenotype was a parietal circular pain of four centimeters' diameter, moderate intensity, and oppressive quality. At baseline, patients had 25 (interquartile range) pain days per month. Preventive treatment was used by 114 (62.3%) patients. The highest 50% and 75% responder rates corresponded to onabotulinumtoxinA (62.5%, 47.5%), followed by gabapentin (43.7%, 35.2%). Oral preventive drugs were not tolerated by 12.9-25%. The present study provides class IV evidence of the effectiveness of oral preventive drugs and onabotulinumtoxinA in the treatment of primary NH. OnabotulinumtoxinA was the most effective and best-tolerated drug, positioning it as first-line treatment of NH.