Vulnerability to Infarction During Cerebral Ischemia in Migraine Sufferers

Cerebrovascular reactivity to hypercapnia in patients with migraine: A dual-echo arterial spin labeling MRI study

OBJECTIVE

This study aimed to compare cerebrovascular reactivity between patients with migraine and controls using state-of-the-art magnetic resonance imaging (MRI) techniques.

BACKGROUND

Migraine is associated with an increased risk of cerebrovascular disease, but the underlying mechanisms are still not fully understood. Impaired cerebrovascular reactivity has been proposed as a link. Previous studies have evaluated cerebrovascular reactivity with different methodologies and results are conflicting.

METHODS

In this single-center, observational, case-control study, we included 31 interictal patients with migraine without aura (aged 19-66 years, 17 females) and 31 controls (aged 22-64 years, 18 females) with no history of vascular disease. Global and regional cerebrovascular reactivities were assessed with a dual-echo arterial spin labeling (ASL) 3.0 T MRI scan of the brain which measured the change in cerebral blood flow (CBF) and BOLD (blood oxygen level dependent) signal to inhalation of 5% carbon dioxide.

RESULTS

When comparing patients with migraine to controls, cerebrovascular reactivity values were similar between the groups, including mean gray matter CBF-based cerebrovascular reactivity (3.2 ± 0.9 vs 3.4 ± 1% ΔCBF/mmHg CO2 ; p = 0.527), mean gray matter BOLD-based cerebrovascular reactivity (0.18 ± 0.04 vs 0.18 ± 0.04% ΔBOLD/mmHg CO2 ; p = 0.587), and mean white matter BOLD-based cerebrovascular reactivity (0.08 ± 0.03 vs 0.08 ± 0.02% ΔBOLD/mmHg CO2 ; p = 0.621).There was no association of cerebrovascular reactivity with monthly migraine days or migraine disease duration (all analyses p > 0.05).

CONCLUSION

Cerebrovascular reactivity to carbon dioxide seems to be preserved in patients with migraine without aura.

Bibliometric Analysis of Research on Migraine-Stroke Association from 2013 to 2023

Background

Both migraine and stroke heavily burden individuals, health systems, and society. The migraine-stroke association is of concern and has been studied widely. Our objective is to explore and overview the current research status and emerging trends.

Materials and Methods

Studies on migraine-stroke association from January 2013 to May 2023 were retrieved and screened from the Web of Science Core Collection (WOSCC) database. Records fulfilling the selection criteria were downloaded and imported into CiteSpace for data mining and visualization.

Results

A total of 862 papers on migraine-stroke association were included. Annual publications grew slowly. The United States and European countries dominated research in this area. Harvard University published the largest number of articles, while the University of London was most active with other institutions. Ayata Cenk contributed the most articles, while KURTH T and NEUROLOGY were co-cited most. Research hotspots included migraine with aura, ischemic stroke, patent foramen ovale, cortical spreading depolarization, meta-analysis, cross-sectional study, and risk factors. Pathophysiology and small vessel disease represented research frontiers and emerging trends.

Conclusion

Our study scientifically outlines the migraine-stroke association over the past decade, presenting useful information.

Neurological and psychiatric comorbidities of migraine: Concepts and future perspectives

BACKGROUND

This narrative review aims to discuss several common neurological and psychiatric disorders that show comorbidity with migraine. Not only can we gain pathophysiological insights by studying these disorders, comorbidities also have important implications for treating migraine patients in clinical practice.

METHODS

A literature search on PubMed and Embase was conducted with the keywords "comorbidity", "migraine disorders", "migraine with aura", "migraine without aura", "depression", "depressive disorders", "epilepsy", "stroke", "patent foramen ovale", "sleep wake disorders", "restless legs syndrome", "genetics", "therapeutics".

RESULTS

Several common neurological and psychiatric disorders show comorbidity with migraine. Major depression and migraine show bidirectional causality and have shared genetic factors. Dysregulation of both hypothalamic and thalamic pathways have been implicated as a possibly cause. The increased risk of ischaemic stroke in migraine likely involves spreading depolarizations. Epilepsy is not only bidirectionally related to migraine, but is also co-occurring in monogenic migraine syndromes. Neuronal hyperexcitability is an important overlapping mechanism between these conditions. Hypothalamic dysfunction is suggested as the underlying mechanism for comorbidity between sleep disorders and migraine and might explain altered circadian timing in migraine.

CONCLUSION

These comorbid conditions in migraine with distinct pathophysiological mechanisms have important implications for best treatment choices and may provide clues for future approaches.

Stroke territory and atherosclerosis in ischemic stroke patients with a history of migraine with aura

Introduction

The mechanisms subtending the increased stroke risk in migraine with aura (MA) are not fully understood. Our study aims to evaluate if the clinical profile in stroke patients with MA differentiates from those without MA.

Methods

We retrieved the prospective registered electronic clinical dossiers of adult patients younger than 60 years with acute ischemic stroke admitted in four hospitals between January 2016 and June 2022. Patients were classified by the history of MA (MA+ and MA-).

Results

We identified 851 stroke patients (59 MA+, 6.9%). Compared to MA-, MA+ patients were characterized by younger age (44.0 ± 10.6 vs 50.1 ± 8.2 years), female sex (59.3% vs 29.0%), and affected by cryptogenic (OR 2.594 95% CI 1.483-4.537), and cerebellar stroke (OR 3.218 95% CI 1.657-6.250; p ≤ 0.001 for all comparisons). After adjusting for age and sex, MA+ patients presented less frequently hypertension (OR 0.349 95% CI 0.167-0.470; p=0.005) and dyslipidemia (OR 0.523 95% CI 0.280-0.974; p = 0.041). After adjusting also for risk factors, the MA+ group had less frequently symptomatic large vessel stenosis (OR 0.126 95% CI 0.017-0,924; p = 0.042) and clinical atherosclerosis (OR 0.103 95% CI 0.014-0.761; p = 0.026), while intima-media thickness did not differ (p = 0.395).

Discussion

Cryptogenic and cerebellar stroke and fewer vascular risk factors and clinical atherosclerosis seem to characterize stroke patients with MA.

Cerebrovascular reactivity and deep white matter hyperintensities in migraine: A prospective CO2 targeting study

Several studies suggested the association of migraine with deep white matter hyperintensities (WMHs). We aimed to explore the cerebrovascular reactivity (CVR), deep WMH burden, and their association in patients with migraine using a state-of-the-art methodology. A total of 31 patients with migraine without aura and 31 age/sex-matched controls underwent 3T MRI with prospective end-tidal carbon dioxide (CO₂) targeting. We quantified deep WMH clusters using an automated segmentation tool and measured voxel-wise CVR by changes in blood oxygen level-dependent signal fitted to subjects' end-tidal CO₂. The association of migraine and CVR with the presence of WMH in each voxel and interaction of migraine and CVR on WMH were analysed. Patients had a higher number of deep WMHs than controls (p = 0.015). Migraine and reduced CVR were associated with increased probability of having WMHs in each voxel (adjusted OR 30.78 [95% CI 1.89-500.53], p = 0.016 and adjusted OR 0.30 [0.29-0.32], p < 0.001, respectively). Migraine had an effect modification on CVR on deep WMHs (p for interaction <0.001): i.e. the association between CVR and WMH was greater in patients than in controls. We suggest that the migraine-WMH association can be explained by the effect modification on the CVR.

Cerebral Hemodynamics, Right-to-Left Shunt and White Matter Hyperintensities in Patients with Migraine with Aura, Young Stroke Patients and Controls

Background: Migraine with aura (MA) patients present an increased risk of cerebrovascular events. However, whether these patients present an increased white matter hyperintensities (WMHs) load compared to the general population is still under debate. Our study aimed to evaluate the relationship between cerebral hemodynamics, right-to-left shunt (RLS) and WMHs in MA patients, young patients with cryptogenic stroke or motor transient ischemic attack (TIA) and controls. Methods: We enrolled 30 MA patients, 20 young (<60 years) patients with cryptogenic stroke/motor TIA, and 10 controls. All the subjects underwent a transcranial Doppler bubble test to detect RLS and cerebral hemodynamics assessed by the breath holding index (BHI) for the middle (MCA) and posterior (PCA) cerebral arteries. Vascular risk factors were collected. The WMHs load on FLAIR MRI sequences was quantitatively assessed. Results: The stroke/TIA patients presented a higher prevalence of RLS (100%) compared with the other groups (p < 0.001). The MA patients presented a higher BHI compared with the other groups in the PCA (p = 0.010) and higher RLS prevalence (60%) than controls (30%) (p < 0.001). The WMHs load did not differ across groups. BHI and RLS were not correlated to the WMHs load in the groups. Conclusions: A preserved or more reactive cerebral hemodynamics and the presence of a RLS are likely not involved in the genesis of WMHs in MA patients. A higher BHI may counteract the risk related to their higher prevalence of RLS. These results need to be confirmed by further studies to be able to effectively identify the protective role of cerebral hemodynamics in the increased RLS frequency in MA patients.

Myocardial infarction, stroke and cardiovascular mortality among migraine patients: a systematic review and meta-analysis

BACKGROUND

An increasing number of studies have shown an association between migraine and cardiovascular disease, in particular cardio- and cerebro-vascular events.

METHODS

Three electronic databases (PubMed, Embase and Scopus) were searched from inception to May 22, 2021 for prospective cohort studies evaluating the risk of myocardial infarction, stroke and cardiovascular mortality in migraine patients. A random effects meta-analysis model was used to summarize the included studies.

RESULTS

A total of 18 prospective cohort studies were included consisting of 370,050 migraine patients and 1,387,539 controls. Migraine was associated with myocardial infarction (hazard ratio, 1.36; 95% CI, 1.23-1.51; p =  < 0.001), unspecified stroke (hazard ratio, 1.30; 95% CI, 1.07-1.60; p = 0.01), ischemic stroke (hazard ratio, 1.35; 95% CI, 1.03-1.78; p = 0.03) and hemorrhagic stroke (hazard ratio, 1.43; 95% CI, 1.07-1.92; p = 0.02). Subgroup analysis of migraine with aura found a further increase in risk of myocardial infarction and both ischemic and hemorrhagic stroke, as well as improved substantial statistical heterogeneity. Migraine with aura was also associated with an increased risk of cardiovascular mortality (hazard ratio, 1.27; 95% CI, 1.14-1.42; p =  < 0.001).

CONCLUSION

Migraine, especially migraine with aura, is associated with myocardial infarction and stroke. Migraine with aura increases the risk of overall cardiovascular mortality.

Breakthroughs on the clinical management of headache and questions that need to be solved

Headache is a common refractory disorder among adults, especially in females, which can lower the quality of life in patients and increase medical costs. Nearly 90% of people have been affected by headache disorders during their lifetime. The severe situation of headaches has drawn the attention of researchers in recent years. Although the mechanism of headache has not been fully understood by us, there are many effective preventive drugs and treatments available. This review is aimed to sum up the progress in clinical trials of headaches in the past 5 years.

Thrombophilic alterations, migraine, and vascular disease: results from a case-control study

BACKGROUND

The association between thrombophilic alterations, migraine, and vascular events has been broadly investigated but not been completely clarified.

METHODS

In this cross-sectional, case-control study, we included consecutive outpatients diagnosed with migraine referring to a tertiary headache center. Migraine patients were matched to headache-free control subjects. All participants were evaluated for free protein S anticoagulant, functional protein C anticoagulant, homocysteine, and antiphospholipid antibodies (aPLs). History of ischemic stroke (IS) or transient ischemic attack (TIA), coronary heart disease, and peripheral venous thrombosis was also ascertained.

RESULTS

We included 329 migraine patients and 329 control subjects (mean age 41 years, 77% women in both groups). Among migraine patients, 239 (72.6%) had migraine without aura and 90 (27.4%) had migraine with aura. Migraine patients had more frequently arterial hypertension, hypercholesterolemia, history of IS or TIA and, peripheral venous thrombosis compared to control subjects, whereas we found no differences in diabetes mellitus, BMI, and coronary heart disease between the two groups. At least one thrombophilic alteration was detected in 107 (32.5%) migraine patients and in 74 (22.5%) control subjects (OR = 1.66, 95% CI 1.17-2.35, p = 0.004). We identified an association of migraine with aPL positivity (OR = 2.6, 95% CI 1.5-4.7, p = 0.001) and with free protein S deficiency (OR = 4.7, 95% CI 1.6-14.0, p = 0.002), whereas we found no differences in protein C deficiency, APCR, and hyperhomocysteinemia between the two groups. Furthermore, aPL positivity and free protein S deficiency were more common in migraine patients with and without aura than in control subjects. We found that in migraine patients, aPL positivity was associated with both IS or TIA (OR = 5.6, 95% CI 1.5-20.4, p = 0.009) and with coronary heart disease (OR = 27.6, 95% CI 1.4-531.1, p = 0.028), whereas free protein S deficiency was associated with IS or TIA only (OR = 14.3, 95% CI 2.8-74.4, p = 0.002).

CONCLUSIONS

Our research documented a significative higher prevalence of aPL positivity and protein S deficiency in migraineurs than in controls. Data also showed an association between these alterations and some vascular thrombotic events in migraine patients. We can argue that thrombophilic disorders associated with migraine may contribute to the occurrence of vascular events.

Shorter visual aura characterizes young and middle-aged stroke patients with migraine with aura

OBJECTIVE

To identify the clinical profile and aura characteristics of patients with Migraine with Aura (MwA) having acute cerebral ischemia, we compared stroke phenotype and risk factors in stroke patients with (S+MwA+) or without (S+MwA-) MwA and aura features in MwA patients with (S+MwA+) or without (S-MwA+) stroke.

METHODS

In this retrospective multicenter case-control study, we reviewed stroke phenotypes and vascular risk factors in S+MwA+ and S+MwA- patients younger than 60 years and risk factors and aura type, duration, onset age, and the frequency in the previous year in S+MwA+ patients and S-MwA+ subjects matched for age and disease history, investigated for patent foramen ovale (PFO).

RESULTS

539 stroke (7.7% S+MwA+) and 94 S-MwA + patients were enrolled. S+MwA+ patients were younger (p =.0.004) and more frequently presented PFO [OR 4.89 (95% CI 2.12-11.27)], septal interatrial aneurism [OR 2.69 (95% CI 1.15-6.27)] and cryptogenic ischemic stroke (CIS) [OR 6.80 (95% CI 3.26-14.18)] than S+MwA- subjects. Significant atherosclerosis was not detected in S+MwA+ patients. Compared to S-MwA+, S+MwA+ patients were characterized by visual [OR 3.82 (95% CI 1.36-10.66)] and shorter-lasting (20.0 min IQr 13.1 vs 30.0 min IQr 25.0; p < 0.001) aura, and PFO [OR 1.26 (95% CI 1.03-1.54)]. Regression analysis evidenced that only shorter aura duration associated with stroke (p = 0.001). High-risk PFO was equally represented in S+MwA-, S+MwA+, S-MwA+ groups.

CONCLUSIONS

Shorter visual aura and CIS characterize MwA patients with stroke. Although more prevalent, PFO can not be considered the main responsible for the increased stroke risk in MwA patients but as a part of a complex multifactorial condition.

Brain Energy Deficit as a Source of Oxidative Stress in Migraine: A Molecular Basis for Migraine Susceptibility

People with migraine are prone to a brain energy deficit between attacks, through increased energy demand (hyperexcitable brain) or decreased supply (mitochondrial impairment). However, it is uncertain how this precipitates an acute attack. Here, the central role of oxidative stress is adduced. Specifically, neurons' antioxidant defenses rest ultimately on internally generated NADPH (reduced nicotinamide adenine dinucleotide phosphate), whose levels are tightly coupled to energy production. Mitochondrial NADPH is produced primarily by enzymes involved in energy generation, including isocitrate dehydrogenase of the Krebs (tricarboxylic acid) cycle; and an enzyme, nicotinamide nucleotide transhydrogenase (NNT), that depends on the Krebs cycle and oxidative phosphorylation to function, and that works in reverse, consuming antioxidants, when energy generation fails. In migraine aura, cortical spreading depression (CSD) causes an initial severe drop in level of NADH (reduced nicotinamide adenine dinucleotide), causing NNT to impair antioxidant defense. This is followed by functional hypoxia and a rebound in NADH, in which the electron transport chain overproduces oxidants. In migraine without aura, a similar biphasic fluctuation in NADH very likely generates oxidants in cortical regions farthest from capillaries and penetrating arterioles. Thus, the perturbations in brain energy demand and/or production seen in migraine are likely sufficient to cause oxidative stress, triggering an attack through oxidant-sensing nociceptive ion channels. Implications are discussed for the development of new classes of migraine preventives, for the current use of C57BL/6J mice (which lack NNT) in preclinical studies of migraine, for how a microembolism initiates CSD, and for how CSD can trigger a migraine.

Pathophysiological Bases of Comorbidity in Migraine

Despite that it is commonly accepted that migraine is a disorder of the nervous system with a prominent genetic basis, it is comorbid with a plethora of medical conditions. Several studies have found bidirectional comorbidity between migraine and different disorders including neurological, psychiatric, cardio- and cerebrovascular, gastrointestinal, metaboloendocrine, and immunological conditions. Each of these has its own genetic load and shares some common characteristics with migraine. The bidirectional mechanisms that are likely to underlie this extensive comorbidity between migraine and other diseases are manifold. Comorbid pathologies can induce and promote thalamocortical network dysexcitability, multi-organ transient or persistent pro-inflammatory state, and disproportionate energetic needs in a variable combination, which in turn may be causative mechanisms of the activation of an ample defensive system with includes the trigeminovascular system in conjunction with the neuroendocrine hypothalamic system. This strategy is designed to maintain brain homeostasis by regulating homeostatic needs, such as normal subcortico-cortical excitability, energy balance, osmoregulation, and emotional response. In this light, the treatment of migraine should always involves a multidisciplinary approach, aimed at identifying and, if necessary, eliminating possible risk and comorbidity factors.

White Matter Lesions in Migraine

Migraine, the third most common disease worldwide, is a well-known independent risk factor for subclinical focal deep white matter lesions (WMLs), even in young and otherwise healthy individuals with no cardiovascular risk factors. These WMLs are more commonly seen in migraine patients with transient neurologic symptoms preceding their headaches, the so-called aura, and those with a high attack frequency. The pathophysiology of migraine-related deep white matter hyperintensities remains poorly understood despite their prevalence. Characteristic differences in their distribution related to chronic small vessel ischemic disease compared with that of common periventricular WMLs in the elderly suggest a different underlying mechanism. Both ischemic and inflammatory mechanisms have been proposed, as there is increased cerebral vulnerability to ischemia in migraineurs, whereas there is also evidence of blood-brain barrier disruption with associated release of proinflammatory substances during migraine attacks. An enhanced susceptibility to spreading depolarization, the electrophysiological event underlying migraine, may be the mechanism that causes repetitive episodes of cerebral hypoperfusion and neuroinflammation during migraine attacks. WMLs can negatively affect both physical and cognitive function, underscoring the public health importance of migraine, and suggesting that migraine is an important contributor to neurologic deficits in the general population.

Cardiac sources of cerebral embolism in people with migraine

BACKGROUND AND PURPOSE

Whether the reported association between migraine with aura (MA) and cardioembolic stroke may be explained by a higher rate of atrial fibrillation (AF) or by other potential cardiac sources of cerebral embolism remains to be determined.

METHODS

In the setting of a single centre cohort study of consecutive patients with acute brain ischaemia stratified by migraine status, the association between AF as well as patent foramen ovale (PFO) and migraine was explored.

RESULTS

In all, 1738 patients (1017 [58.5%] men, mean age 67.9 ± 14.9 years) qualified for the analysis. Aging was inversely associated with migraine, whilst women had a >3-fold increased disease risk (odds ratio [OR] 3.82, 95% confidence interval [CI] 2.58-5.66). No association between AF and history of migraine or its pathogenic subtypes was detected. Conversely, migraine was associated with PFO, both in the entire cohort (OR 1.84, 95% CI 1.07-3.16) and in patients aged ≤55 years (OR 2.21, 95% CI 1.16-4.22). This association was significant for MA (OR 2.92, 95% CI 1.32-6.45 in the entire cohort; OR 2.92, 95% CI 1.15-7.41 in patients aged ≤55 years) and in women (OR 8.23, 95% CI 2.06-32.77), but not for migraine without aura.

CONCLUSIONS

In patients with brain ischaemia migraine is not associated with AF. Conversely, there is a probable relation between migraine, especially MA, and PFO in patients who are younger and have a more favourable vascular risk factor profile, and in women.

rLj-RGD4, the shortened peptide of rLj-RGD3 from Lampetra japonica, protects against cerebral ischemia/reperfusion injury via the PI3K/Akt pathway

The toxic RGD peptide, rLj-RGD4, characterized by 4 (Arg-Gly-Asp) (RGD) motifs, is a novel mutant of rLj-RGD3 from the salivary gland of Lampetra japonica. Our previous study showd that rLj-RGD3 exerts a protective effect against cerebral ischemia injury in rats. Through the induction of middle cerebral artery occlusion/reperfusion (MCAO) injuries in rats, the present study investigated the effects and the mechanism through which rLj-RGD4 protects against ischemic stroke. In rats, treatment with rLj-RGD4 2 h after MCAO enhanced survival rate, improved movement and ameliorated the severity of brain infarction and apoptosis by diminishing pathological changes. This study demonstrated that rLj-RGD4 can reverse the downregulation of Bcl2, and the upregulation of Caspase-3. Mechanistic studies showed that rLj-RGD4 upregulated the expression levels of FAK, p-FAK, PI3K and p-Akt. In contrast, caspase-3 expression was inhibited. These results showed that rLj-RGD4 may reduce cerebral ischemia-reperfusion injury.

Migraine and risk of stroke

Migraine and stroke are two common and heterogeneous neurovascular disorders responsible for a significant burden for those affected and a great economic cost for the society. There is growing evidence that migraine increases the overall risk of cerebrovascular diseases. In this review, based on available literature through a PubMed search, we found that ischaemic stroke in people with migraine is strongly associated with migraine with aura, young age, female sex, use of oral contraceptives and smoking habits. The risk of transient ischaemic attack also seems to be increased in people with migraine, although this issue has not been extensively investigated. Although migraine appears to be associated with haemorrhagic stroke, the migraine aura status has a small influence on this relationship. Neuroimaging studies have revealed a higher prevalence of asymptomatic structural brain lesions in people with migraine. They are also more likely to have unfavourable vascular risk factors; however, the increased risk of stroke seems to be more apparent among people with migraine without traditional risk factors. The mechanism behind the migraine-stroke association is unknown. In light of the higher risk of stroke in people with migraine with aura, it is important to identify and modify any vascular risk factor. There is currently no direct evidence to support that a migraine prophylactic treatment can reduce future stroke in people with migraine.

Is there a timing for sensitivity to acute cerebral ischemia in migraine patients?

BACKGROUND

Migraine may be a factor of increased cerebral sensitivity to ischemia. Previous studies were conducted within 6 to 72 after stroke onset. We aimed to determine if an accelerated infarct growth exists in migraine patients within the first 4.5 h.

METHOD

A retrospective case-control study was conducted where all patients admitted for acute stroke started <4.5 h before and who underwent perfusion CT were assessed. The hypoperfusion and necrosis volumes on initial CT perfusion were analyzed, as well as the final infarct volume on MRI performed within 72 h after admission. A no-mismatch pattern was defined as a ratio necrosis/hypoperfusion volume > 83%.

RESULTS

24 patients with personal history of migraine were identified, 8 of them with aura. The control cohort included 51 patients. No difference was found between groups in terms of demographics, initial severity or outcome or presumed cause of stroke. Mean time to CT scan was 125 min in migraine patients and 127 min in the control group. A no-mismatch pattern was equally found in migraine patients and controls, even after adjustment for age, sex and presence of proximal occlusion (p = .22). The final infarct volume was also similar in both groups.

CONCLUSIONS

Migraine patients did not display more no-mismatch pattern than controls within the 4.5 h of stroke onset. This deviates from previous studies and may be due to our earlier time from stroke onset to CT scan. A history of migraine may lead to malignant progression of ischemia but occurring only after several hours.

History of Migraine and Volume of Brain Infarcts: The Italian Project on Stroke at Young Age (IPSYS)

Background and Purpose

Migraine has been shown to increase cerebral excitability, promote rapid infarct expansion into tissue with perfusion deficits, and result in larger infarcts in animal models of focal cerebral ischemia. Whether these effects occur in humans has never been properly investigated.

Methods

In a series of consecutive patients with acute ischemic stroke, enrolled in the setting of the Italian Project on Stroke at Young Age, we assessed acute as well as chronic infarct volumes by volumetric magnetic resonance imaging, and compared these among different subgroups identified by migraine status.

Results

A cohort of 591 patients (male, 53.8%; mean age, 37.5±6.4 years) qualified for the analysis. Migraineurs had larger acute infarcts than non-migraineurs (median, 5.9 cm³ [interquartile range (IQR), 1.4 to 15.5] vs. 2.6 cm³ [IQR, 0.8 to 10.1], P<0.001), and the largest volumes were observed in patients with migraine with aura (median, 9.0 cm³ [IQR, 3.4 to 16.6]). In a linear regression model, migraine was an independent predictor of increased log (acute infarct volumes) (median ratio [MR], 1.64; 95% confidence interval [CI], 1.22 to 2.20), an effect that was more prominent for migraine with aura (MR, 2.92; 95% CI, 1.88 to 4.54).

Conclusions

These findings reinforce the experimental observation of larger acute cerebral infarcts in migraineurs, extend animal data to human disease, and support the hypothesis of increased vulnerability to ischemic brain injury in people suffering migraine.

Right-to-left shunts and hormonal therapy influence cerebral vasomotor reactivity in patients with migraine with aura

Patent Foramen Ovale and impaired cerebral hemodynamics were proposed among the pathophysiological mechanisms explaining the increased risk for stroke in patients with Migraine with Aura (MA). Our study aimed at comparing the vasomotor reactivity (VMR) of the anterior and the posterior cerebral circulation in patients with Migraine with Aura, in patients with acute vascular ischemic accidents, and in controls. We hypothesized that VMR in MA patients is preserved in the anterior circulation and reduced in the posterior circulation. We prospectively assessed with Transcranial Doppler the vasomotor reactivity to breath holding of the Middle and Posterior Cerebral Arteries (MCA, PCA) in MA patients, in acute vascular patients and healthy controls. We also evaluated the possible effect of clinical characteristics of MA (attack frequency, aura length or type, disease history), vascular factors and the presence of right-to-left shunt on VMR. Diverging from our hypothesis, MA patients displayed a higher breath-holding index (BHI) than controls in the MCA (1.84±0.47%/s vs 1.53±0.47%/s, p = .001) as well as in the PCA (1.87±0.65%/s vs 1.47±0.44%/s, p < .001). In MA patients, MCA BHI was higher in those with large right-to-left shunts (2.09±0.42 vs 1.79±0.47, p = .046) and lower in those taking estrogens (1.30±0.30%/s vs 1.9±0.45%/s, p = .009). We did not observe an effect of MA characteristics on BHI. The increased BHI in MA patients with large right-to-left shunts could be explained by the vasoactive effect in the cerebral circulation of substances bypassing the deactivating pulmonary filters or by a constitutional trait of the vascular system associating persistent right-to-left shunts and hyper-reactive hemodynamics. Our results discourage the hypothesis that altered hemodynamics contribute to increasing the stroke risk in all MA patients. However, estrogens can lower VMR, curtailing the hemodynamic resources of MA patients.

Aura and Stroke: relationship and what we have learnt from preclinical models

BACKGROUND

Population-based studies have highlighted a close relationship between migraine and stroke. Migraine, especially with aura, is a risk factor for both ischemic and hemorrhagic stroke. Interestingly, stroke risk is highest for migraineurs who are young and otherwise healthy.

MAIN BODY

Preclinical models have provided us with possible mechanisms to explain the increased vulnerability of migraineurs' brains towards ischemia and suggest a key role for enhanced cerebral excitability and increased incidence of microembolic events. Spreading depolarization (SD), a slowly propagating wave of neuronal depolarization, is the electrophysiologic event underlying migraine aura and a known headache trigger. Increased SD susceptibility has been demonstrated in migraine animal models, including transgenic mice carrying human mutations for the migraine-associated syndrome CADASIL and familial hemiplegic migraine (type 1 and 2). Upon experimentally induced SD, these mice develop aura-like neurological symptoms, akin to patients with the respective mutations. Migraine mutant mice also exhibit an increased frequency of ischemia-triggered SDs upon experimental stroke, associated with accelerated infarct growth and worse outcomes. The severe stroke phenotype can be explained by SD-related downstream events that exacerbate the metabolic mismatch, including pericyte contraction and neuroglial inflammation. Pharmacological suppression of the genetically enhanced SD susceptibility normalizes the stroke phenotype in familial hemiplegic migraine mutant mice. Recent epidemiologic and imaging studies suggest that these preclinical findings can be extrapolated to migraine patients. Migraine patients are at risk for particularly cardioembolic stroke. At the same time, studies suggest an increased incidence of coagulopathy, atrial fibrillation and patent foramen ovale among migraineurs, providing a possible path for microembolic induction of SD and, in rare instances, stroke in hyperexcitable brains. Indeed, recent imaging studies document an accelerated infarct progression with only little potentially salvageable brain tissue in acute stroke patients with a migraine history, suggesting an increased vulnerability towards cerebral ischemia.

CONCLUSION

Preclinical models suggest a key role for enhanced SD susceptibility and microembolization to explain both the occurrence of migraine attacks and the increased stroke risk in migraineurs. Therapeutic targeting of SD and microembolic events, or potential causes thereof, will be promising for treatment of aura and may also prevent ischemic infarction in vulnerable brains.

Paradoxical association between age and cerebrovascular reactivity in migraine: A cross-sectional study

BACKGROUND

Previous studies reported an increased risk of ischemic stroke in younger migraineurs. We aimed to investigate the association between age and cerebrovascular reactivity (CVR) to vasodilatory stimuli in cerebral arteries in patients with migraine and normal controls.

METHODS

In this cross-sectional study, we recruited 248 patients with migraine and 105 normal controls at Samsung Medical Center between October 2015 and July 2018. CVR was measured interictally by using the transcranial Doppler breath-holding test. For the arteries which showed a correlation between age and CVR, we conducted univariable and multivariable linear regression analysis to assess the independent effect of age on CVR. The path analysis was performed to assess mediating effects of the age of onset and disease duration on the age-CVR association.

RESULTS

Patients had reduced CVR in all tested arteries compared to normal controls. A correlation between age and CVR was present in the posterior cerebral artery (PCA) only in patients (Pearson's correlation coefficient = 0.160, p = 0.012). In patients, younger age was independently associated with lower CVR in the PCA (multivariable B = 0.003, 95% CI = 0.0002-0.005, p = 0.033 adjusted for sex, migraine subtype, and headache frequencies). The path analysis showed that the age of onset fully mediated the effect of age on PCA CVR, while longer disease duration negatively modified the effect of age of onset (p for interaction = 0.018).

CONCLUSIONS

In migraineurs, younger age was associated with CVR reduction in the PCA. Younger age of onset may be a hidden risk factor mediating the paradoxical association between age and CVR. This association might explain an increased risk of stroke in younger migraineurs.

Radiologic Cerebral Reperfusion at 24 h Predicts Good Clinical Outcome

Cerebral reperfusion and arterial recanalization are radiological features of the effectiveness of thrombolysis in acute ischemic stroke (AIS) patients. Here, an investigation of the prognostic role of early recanalization/reperfusion on clinical outcome was performed. In AIS patients (n = 55), baseline computerized tomography (CT) was performed ≤ 8 h from symptom onset, whereas CT determination of reperfusion/recanalization was assessed at 24 h. Multiple linear and logistic regression models were used to correlate reperfusion/recanalization with radiological (i.e., hemorrhagic transformation, ischemic core, and penumbra volumes) and clinical outcomes (assessed as National Institutes of Health Stroke Scale [NIHSS] reduction ≥ 8 points or a NIHSS ≤ 1 at 24 h and as modified Rankin Scale [mRS] < 2 at 90 days). At 24 h, patients achieving radiological reperfusion were n = 24, while the non-reperfused were n = 31. Among non-reperfused, n = 15 patients were recanalized. Radiological reperfusion vs. recanalization was also confirmed by early increased levels of circulating inflammatory biomarkers (i.e., serum osteopontin). In multivariate analysis, ischemic lesion volume reduction was associated with both recanalization (β = 0.265; p = 0.014) and reperfusion (β = 0.461; p < 0.001), but only reperfusion was independently associated with final infarct volume (β = - 0.333; p = 0.007). Only radiological reperfusion at 24 h predicted good clinical response at day 1 (adjusted OR 16.054 [1.423-181.158]; p = 0.025) and 90-day good functional outcome (adjusted OR 25.801 [1.483-448.840]; p = 0.026). At ROC curve analysis the AUC of reperfusion was 0.777 (p < 0.001) for the good clinical response at 24 h and 0.792 (p < 0.001) for 90-day clinical outcome. Twenty-four-hour radiological reperfusion assessed by CT is associated with good clinical response on day 1 and good functional outcome on day 90 in patients with ischemic stroke.