Our Evolving Understanding of Migraine with Aura

Effect of anti-CGRP-targeted therapy on migraine aura: Results of an observational case series study

INTRODUCTION

Limited clinical evidence is available regarding the potential effectiveness of anti-CGRP monoclonal antibodies for the preventive treatment of migraine with aura.

AIM OF THE STUDY

This observational study involved a series of migraine patients affected by either migraine with or without aura, who were investigated for any changes in their frequencies and their migraine aura attack characteristics observed during treatment with anti-CGRP Mabs over a 1-year period.

PATIENTS AND METHODS

Twelve migraine patients were included, seven of whom were treated with erenumab, 2 with fremanezumab, and 3 with galcanezumab. Clinical data were collected at baseline, which were defined as 3 months prior to the initiation of treatment, and thereafter at each trimester, over the 1-year treatment period. The parameters included the number of headache and migraine days/month, the frequency of aura episodes, the number of days with acute drug intakes/month, and the scores from the migraine disability status scale (MIDAS), and the Headache Impact Test 6 (HIT-6).

RESULTS

Anti-CGRP Mbs antibodies induced significant decreases in mean headache and migraine without aura days per month, the number of days with medication intake, as well as MIDAS and HIT-6 scores (p < 0.0001). In contrast, the anti-CGRP Mab treatment did not appear to impact the frequency of migraine with aura attacks but seemed to reduce both the intensity and the duration of headache phases of migraine aura. Furthermore, some migraine patients referred to having aura attacks without headache over the course of the treatment period.

CONCLUSIONS

Based on the above findings, we hypothesize that anti-CGRP Mabs did not influence neuronal and vascular events related to cortical spreading depression (CSD) which is considered the pathophysiological substrate of aura. Conversely, these antibodies are able to counteract, via their peripheral mechanisms of action, the sensitization of the trigemino-vascular pathway which is triggered by CSD. This aforementioned might explain why in our patients, migraine aura attacks remained unchanged in their frequencies, but the headache phases were either reduced or absent.

Pathophysiology of migraine aura

Migraine aura occurs in about a third of patients with migraine and consists of a group of transient focal neurological symptoms that appear from 5 to 60min and then resolve prior to or in the early phase of a migraine headache attack. Migraine auras may consist of visual, language, unilateral sensory, or motor symptoms. There has been considerable debate as to the origins of the migrainous aura. Investigations during physiologically induced visual auras suggest that the phenomenon of cortical spreading depression or its human equivalent underpins the migraine aura. Single gene defects have been linked to relatively rare forms of the motor subtypes of aura known as familial hemiplegic migraine (FHM). These include CACNA1A (FHM1), ATP1A2 (FHM2), and SCN1A (FHM3). In the familial hemiplegic forms of migraine, the more typical forms of aura are almost always also present. Despite ample epidemiological evidence of increased heritability of migraine with aura compared to migraine without aura, identification of the specific variants driving susceptibility to the more common forms of aura has been problematic thus far. In the first genome-wide association study (GWAS) that focused migraine with aura, a single SNP rs835740 reached genome-wide significance. Unfortunately, the SNP did show statistical significance in a later meta-analysis which included GWAS data from subsequent studies. Here, we review the clinical features, pathophysiological theories, and currently available potential evidence for the genetic basis of migraine aura.

The Role of the Inner Nuclear Layer for Perception of Persisting Tiling Inside a Monocular Scotoma

We report two patients, one with and one without long-term persistent tiling inside an arcuate macular scotoma. In both cases, the scotoma was caused by a cilioretinal artery occlusion. Both patients were almost identical regarding the location and extent of the scotoma. In both cases, there was a comparable degree of atrophy on optical coherence tomography for the retinal nerve fibre, ganglion cell, and inner plexiform layers. The main difference was the preservation of the inner nuclear layer in the patient with persistent tiling. In this patient, optical coherence angiography demonstrates preserved perfusion of the superior vascular plexus, which was not the case in the patient with the negative scotoma who also had atrophy of the inner nuclear layer. Recreational use of cannabinoid enhanced the intensity of perceived tiling in the relative scotoma of the first patient. A review of the literature suggests that the persistent tiling described in our case is different to teichopsias of retinal or cerebral origin. These data suggest that persistent monocular tiling in a scotoma arises from retinal circuit activity that requires the preservation of the inner nuclear layer. Future research should investigate this functional–structural relationship in other diseases, including glaucoma.

The beneficial effect of Alpha-lipoic acid supplementation as a potential adjunct treatment in episodic migraines

The current study was performed to evaluate the effects of alpha-lipoic acid (ALA) supplementation on lactate, nitric oxide (NO), vascular cell adhesion molecule-1 (VCAM-1) levels, and clinical symptoms in women with episodic migraines. Considering the inclusion and exclusion criteria, ninety-two women with episodic migraines participated in this randomized, double-blind, placebo-controlled, parallel-design trial. The participants were randomly assigned to receive either 300 mg/day ALA or placebo, twice per day for 12 weeks. The primary outcomes included headache severity, headache frequency per month, and duration of attacks and the secondary outcomes included lactate (a marker of mitochondrial function), NO, and VCAM-1 serum levels were measured at baseline and the end of the intervention. At the end of the study, there was a significant decrease in lactate serum levels (- 6.45 ± 0.82 mg/dl vs - 2.27 ± 1.17 mg/dl; P = 0.039) and VCAM-1 (- 2.02 ± 0.30 ng/ml vs - 1.21 ± 0.36 ng/ml; P = 0.025) in the ALA as compared to the placebo group. In addition, the severity (P < 0.001), frequency (P = 0.001), headache impact test (HIT-6) (P < 0.001), headache dairy results (HDR) (P = 0.003), and migraine headache index score (MHIS) (P < 0.001) had significantly decreased in the intervention as compared to the control group. No significant changes were observed for NO levels and duration of migraine pains. ALA supplementation can be considered a potential adjunct treatment in patients with migraine due to its improving mitochondrial and endothelial functions and clinical symptoms.

Renin-Angiotensin-Aldosterone System and Migraine: A Systematic Review of Human Studies

Migraine is a common neurologic condition marked by recurrent episodes of headache. Its pathophysiology is highly complex involving neuronal, inflammatory and vascular mechanisms. The Renin-Angiotensin System (RAS) can modulate all these mechanism, being a potential pharmacological target for migraine treatment. We carried out a systematic review of the studies evaluating the involvement of RAS in patients with migraine. There is evidence from genetic studies exploring the relation between migraine and RAS-related genes and from clinical trials evaluating the efficacy of Angiotensin II Type 1 (AT1) receptor antagonists and angiotensin converting enzyme inhibitors in migraine prophylaxis. RAS seems to play a role in the pathophysiology of migraine, but more direct evidence is still missing.

The index vein pointing to the origin of the migraine aura symptom

Objective

This case series describes and discusses the potential clinical utility of a prominent vein (index vein) found on susceptibility-weighted MRI during migraine aura that drains the cortical area responsible for patients' symptoms.

Methods

Six patients with acute migraine aura had a prominent draining sulcal vein on emergency MRI done initially for suspected stroke. The location of the prominent vein was correlated to patients' symptoms, and the diameter was compared to the corresponding contralateral vein.

Results

In our patients with typical migraine aura, an accentuated sulcal vein pointed towards the cortical area correlating with the clinical presentation. Such an index vein outstands the ipsilateral area of hypoperfusion and exceeds the corresponding contralateral vessel in diameter by a factor 2.0 ± 1.6 (mean ± SD).

Conclusion

This case series provides a definition of an index vein in MRI pointing to the area where the patients' symptoms originate. Although confirmation in a larger systematic study is necessary, the presence of such an index vein might support that, in patients with an acute neurologic deficit, migraine aura is the underlying etiology.

Transient Neurologic Dysfunction in Migraine

Transient disturbances in neurologic function are disturbing features of migraine attacks. Aura types include binocular visual, hemi-sensory, language and unilateral motor symptoms. Because of the gradual spreading quality of visual and sensory symptoms, they were thought to arise from the cerebral cortex. Motor symptoms previously included as a type of migraine aura were reclassified as a component of hemiplegic migraine. ICHD-3 criteria of the International Headache Society, added brainstem aura and retinal aura as separate subtypes. The susceptibility to all types of aura is likely to be included by complex and perhaps epigenetic factors.

Shedding light on migraine with aura: the clarifying role of advanced neuroimaging investigations

Introduction: While migraine with aura is a complex neurological syndrome with a well-characterized clinical phenotype, its pathophysiology still has grey areas which could be partially clarified by microstructural and functional neuroimaging investigations. Areas covered: This article, summarizing the most significant findings from advanced neuroimaging studies, aims to achieve a unifying pathophysiological model of the migraine aura. A comprehensive review has been conducted of PubMed citations by entering the key word 'neuroimaging' combined with 'migraine with aura' AND/OR 'MRI.' Other keywords included 'grey matter' OR 'white matter', 'structural' OR 'functional'. Expert opinion: Converging evidence from advanced neuroimaging investigations underlined the critical role of the extrastriate visual cortex, and in particular the lingual gyrus, in the genesis of the aura phenomenon. However, the relationship between the aura and the headache phase of migraine attacks has not been completely clarified, to date, and underlying pathophysiological mechanisms need to be further elucidated.

Migraine and Tension-Type Headache: Diagnosis and Treatment

Migraine and tension-type headache are highly prevalent. Migraine is associated with significant work- and family-related disability. Migraine is underdiagnosed; it reasonable to err on the side of migraine when choosing between primary headaches. Barriers to appropriate treatment of migraine include lack of access to providers, misdiagnosis, and acute and preventive therapies not being prescribed. Acute, rescue, and preventive treatment options are extensive, and new classes of treatments are either available or in development. This review addresses diagnostic challenges including recognizing migraine with aura. It also summarizes nonpharmacologic, acute, rescue, and preventive treatment options for migraine and treatment of tension-type headache.

The impact of self-administered acupressure on sleep quality and fatigue among patients with migraine: A randomized controlled trial

BACKGROUND AND AIM

Poor sleep and fatigue are among the most common complaints of patients with migraine. These problems can lead to different negative consequences such as headaches. This study aimed to examine the impacts of self-administered acupressure on sleep quality and fatigue among patients with migraine.

METHODS

This double-blind randomized controlled trial was conducted in 2016 on 76 patients who suffered from migraine without aura. Patients were conveniently selected from the neurology clinic of Valiasr (PBUH) teaching hospital and randomly allocated to either an acupressure (n = 38) or a sham acupressure group (n = 38) group. Data collection instruments were a demographic questionnaire, Pittsburg Sleep Quality Index, and Fatigue Severity Scale. Patients in the acupressure and the sham acupressure groups were trained to apply acupressure on respectively acupoints and sham points thrice weekly at bedtime for four consecutive weeks. The data were analyzed through the Chi-square, the independent-sample t, the paired-sample t, and the ANCOVA tests at the significance level of less than 0.05.

RESULTS

After controlling sleep quality mean scores at baseline, no significant difference was found between the sleep quality of the two groups after intervention (P > 0.05). The mean scores of fatigue significantly decreased in both acupressure and sham acupressure groups (P < 0.05). However, the decrease in the acupressure group was significantly greater than in the sham acupressure group (P < 0.05).

CONCLUSION

As a noninvasive non-pharmacological therapy, acupressure can significantly reduce fatigue among patients with migraine.

Migraine-Like Visual Auras Among Traumatized Cambodians with PTSD: Fear of Ghost Attack and Other Disasters

This article profiles visual auras among traumatized Cambodian refugees attending a psychiatric clinic. Thirty-six percent (54/150) had experienced an aura in the previous 4 weeks, almost always phosphenes (48% [26/54]) or a scintillating scotoma (74% [40/54]). Aura and PTSD were highly associated: patients with visual aura in the last month had greater PTSD severity, 3.6 (SD = 1.8) versus 1.9 (SD = 1.6), t = 10.2 (df = 85), p < 0.001, and patients with PTSD had a higher rate of visual aura in the last month, 69% (22/32) versus 13% (7/55), odds ratio 15.1 (5.1-44.9), p < 0.001. Patients often had a visual aura triggered by rising up to the upright from a lying or sitting position, i.e., orthostasis, with the most common sequence being an aura triggered upon orthostasis during a migraine, experienced by 60% of those with aura. The visual aura was often catastrophically interpreted: as the dangerous assault of a supernatural being, most commonly the ghost of someone who died in the Pol Pot period. Aura often triggered flashback. Illustrative cases are provided. The article suggests the existence of local biocultural ontologies of trauma as evinced by the centrality of visual auras among Cambodian refugees.

The role of visual system in migraine

The visual system is involved in different ways in migraine. Visual auras are the most common form of migraine aura. It may consist of positive or negative visual symptoms and cortical spreading depression is felt to be the phenomenon that underlies it. Even in migraine without aura, vision it is not totally excluded given that one of the major criteria for the diagnosis of migraine is photophobia. In persistent visual aura, patients refer symptoms defined as visual snow and television static. In retinal migraine unilateral decreased vision or complete visual loss occurs. Ophthalmoplegic migraine is characterized by palsy of one among the three ocular motor nerves. Migraine visual aura, particularly when occurring without headache, is a diagnosis of exclusion. Imaging studies and laboratory tests should exclude neurologic disease, included seizures and central nervous system tumor, ocular pathologies, carotid or cardiac disease, thrombosis and connective tissue disease.

Preventive drugs restore visual evoked habituation and attention in migraineurs

Visual system pathway dysfunction has been postulated in migraineurs. We wanted to investigate if any difference exists interictally in visual attention and visual evoked habituation of frequently attacked migraineurs compared to the healthy control group. The effects of 3-month prophylactic migraine treatment on these parameters were also assessed. The migraineurs at headache-free interval (n = 52) and age, sex-matched healthy controls (n = 35) were compared by habituation response to 10 blocks of repetitive pattern-reversal visual stimuli (each block consisted 100 responses). The amplitude changes of 5th and 10th blocks were further compared with that of block 1 to assess the response of habituation (i.e., decrease) or potentiation (i.e., increase). The level of sustained visual attention was assessed by Cancellation test. Migraineurs were randomized to three different preventive treatments: propranolol 40 mg tid, flunarizine 5 mg bid, or topiramate 50 mg bid. After 3 months of preventive treatment, migraineurs data were compared with their baseline values. The groups did not differ by sex and age. In electrophysiological studies, the habituation ability observed in the healthy group was not observed in migraineurs. However, it was restored 3 months after preventive treatment. In migraineurs, compared to their baseline values, the distorted visual attention parameters also improved after treatment. All drugs were effective. The loss of habituation ability and low visual attention performance in migraineurs can be restored by migraine preventive treatment. This electrophysiological study accompanied by neuropsychological test may aid an objective and quantitative assessment tool for understanding migraine pathophysiology.

Astrocyte-mediated inflammation in cortical spreading depression

Background Cortical spreading depression (CSD) related diseases such as migraine, cerebrovascular diseases, and epilepsy have been associated with reactive astrocytosis, yet the mechanisms of these tissue changes remain unclear. CSD-induced inflammatory response has been proposed to play a role in some neurological disorders and thus may also contribute to reactive astrocytosis. Methods Using ex vivo brain slices and in vitro astrocytic cultures, we aimed to characterize CSD related changes in astrocytes and markers of inflammation by immunocyto- and immunohistochemistry. CSD was induced by application of KCl (3 mol/l) on neocortical tissues. The application of KCl was repeated weekly over the course of four weeks. Results CSD induced an increase in the mean number and volume of astrocytes in rat brain tissue when compared to controls, whereas no changes in neuronal numbers and volumes were seen. These cell-type specific changes, suggestive of reactive astrocytosis, were paralleled by an increased expression of protein markers indicative of astrocytes and neuroinflammation in ex vivo brain slices of animals undergoing CSD when compared to sham-treated controls. Cultured astrocytes showed an increased expression of the immune modulatory enzyme indoleamine 2,3-dioxygenase and an elevated expression of the pro-inflammatory markers, IL-6, IL-1β, and TNFα in addition to increased levels of toll like receptors (TLR3 and TLR4) and astrocytic markers after induction of CSD. Conclusion These findings indicate that CSD related reactive astrocytosis is linked to an upregulation of inflammatory markers. Targeting inflammation with already approved and available immunomodulatory treatments may thus represent a strategy to combat or ameliorate CSD-related disease.