Structural and functional changes of anterior cingulate cortex subregions in migraine without aura: relationships with pain sensation and pain emotion.

Migraine without aura is a multidimensional neurological disorder characterized by sensory, emotional, and cognitive symptoms linked to structural and functional abnormalities in the anterior cingulate cortex. Anterior cingulate cortex subregions play differential roles in the clinical symptoms of migraine without aura; however, the specific patterns and mechanisms remain unclear. In this study, voxel-based morphometry and seed-based functional connectivity were used to investigate structural and functional alterations in the anterior cingulate cortex subdivisions in 50 patients with migraine without aura and 50 matched healthy controls. Compared with healthy controls, patients exhibited (1) decreased gray matter volume in the subgenual anterior cingulate cortex, (2) increased functional connectivity between the bilateral subgenual anterior cingulate cortex and right middle frontal gyrus, and between the posterior part of anterior cingulate cortex and right middle frontal gyrus, orbital part, and (3) decreased functional connectivity between the anterior cingulate cortex and left anterior cingulate and paracingulate gyri. Notably, left subgenual anterior cingulate cortex was correlated with the duration of each attack, whereas the right subgenual anterior cingulate cortex was associated with migraine-specific quality-of-life questionnaire (emotion) and self-rating anxiety scale scores. Our findings provide new evidence supporting the hypothesis of abnormal anterior cingulate cortex subcircuitry, revealing structural and functional abnormalities in its subregions and emphasizing the potential involvement of the left subgenual anterior cingulate cortex-related pain sensation subcircuit and right subgenual anterior cingulate cortex -related pain emotion subcircuit in migraine.

Abnormal causal connectivity of anterior cingulate cortex-visual cortex circuit related to nonsteroidal anti-inflammatory drug efficacy in migraine.

The anterior cingulate cortex (ACC) and visual cortex are integral components of the neurophysiological mechanisms underlying migraine, yet the impact of altered connectivity patterns between these regions on migraine treatment remains unknown. To elucidate this issue, we investigated the abnormal causal connectivity between the ACC and visual cortex in patients with migraine without aura (MwoA), based on the resting-state functional magnetic resonance imaging data, and its predictive ability for the efficacy of nonsteroidal anti-inflammatory drugs (NSAIDs). The results revealed increased causal connectivity from the bilateral ACC to the lingual gyrus (LG) and decreased connectivity in the opposite direction in nonresponders compared with the responders. Moreover, compared with the healthy controls, nonresponders exhibited heightened causal connectivity from the ACC to the LG, right inferior occipital gyrus (IOG) and left superior occipital gyrus, while connectivity patterns from the LG and right IOG to the ACC were diminished. Based on the observed abnormal connectivity patterns, the support vector machine (SVM) models showed that the area under the receiver operator characteristic curves for the ACC to LG, LG to ACC and bidirectional models were 0.857, 0.898, and 0.939, respectively. These findings indicate that neuroimaging markers of abnormal causal connectivity in the ACC-visual cortex circuit may facilitate clinical decision-making regarding NSAIDs administration for migraine management.

Altered neurovascular coupling in migraine without aura.

Neurovascular coupling (NVC) provides new insights into migraine, a neurological disorder impacting over one billion people worldwide. This study compared NVC and cerebral blood flow (CBF) in patients with migraine without aura (MwoA) and healthy controls. About 55 MwoA patients in the interictal phase and 40 age- and sex-matched healthy controls underwent resting-state functional magnetic resonance imaging and arterial spin-labeling perfusion imaging scans. The CBF and resting-state neuronal activity indicators, including the amplitudes of low-frequency fluctuation (ALFF), regional homogeneity (ReHo), and degree centrality (DC), were calculated for each participant. The global and regional NVCs were assessed using cross-voxel CBF-neuronal activity correlations and CBF/neuronal activity ratios. Patients with MwoA showed increased CBF/ALFF ratios in the left media, superior and inferior frontal gyri, and anterior cingulate gyrus, increased CBF/DC ratios in the left middle and inferior frontal gyri, and increased CBF/ReHo ratios in the right corpus callosum and right posterior cingulate gyrus. Lower CBF/ALFF ratios in the right rectal gyrus, the left orbital gyrus, the right inferior frontal gyrus, and the right superior temporal gyrus were also found in the MwoA patients. Furthermore, the CBF/ALFF ratios in the inferior frontal and superior temporal gyri were positively correlated with the Headache Impact Test scores and Hamilton anxiety scale scores in the MwoA patients. These findings provide evidence for the theory that abnormal NVC contributes to MwoA.

Risk Profile of Patients with Spontaneous Cervical Artery Dissection.

OBJECTIVE: Epidemiological data to characterize the individual risk profile of patients with spontaneous cervical artery dissection (sCeAD) are rather inconsistent. METHODS AND RESULTS: In the setting of the Italian Project on Stroke in Young Adults Cervical Artery Dissection (IPSYS CeAD), we compared the characteristics of 1,468 patients with sCeAD (mean age = 47.3 ± 11.3 years, men = 56.7%) prospectively recruited at 39 Italian centers with those of 2 control groups, composed of (1) patients whose ischemic stroke was caused by mechanisms other than dissection (non-CeAD IS) selected from the prospective IPSYS registry and Brescia Stroke Registry and (2) stroke-free individuals selected from the staff members of participating hospitals, matched 1:1:1 by sex, age, and race. Compared to stroke-free subjects, patients with sCeAD were more likely to be hypertensive (odds ratio [OR] = 1.65, 95% confidence interval [CI] = 1.37-1.98), to have personal history of migraine with aura (OR = 2.45, 95% CI = 1.74-3.34), without aura (OR = 2.67, 95% CI = 2.15-3.32), and family history of vascular disease in first-degree relatives (OR = 1.69, 95% CI = 1.39-2.05), and less likely to be diabetic (OR = 0.65, 95% CI = 0.47-0.91), hypercholesterolemic (OR = 0.75, 95% CI = 0.62-0.91), and obese (OR = 0.41, 95% CI = 0.31-0.54). Migraine without aura was also associated with sCeAD (OR = 1.81, 95% CI = 1.47-2.22) in comparison with patients with non-CeAD IS. In the subgroup of patients with migraine, patients with sCeAD had higher frequency of migraine attacks and were less likely to take anti-migraine preventive medications, especially beta-blockers, compared with the other groups. INTERPRETATION: The risk of sCeAD is influenced by migraine, especially migraine without aura, more than by other factors, increases with increasing frequency of attacks, and seems to be reduced by migraine preventive medications, namely beta-blockers. ANN NEUROL 2023;94:585-595.

Enhanced audiovisual associative pair learning in migraine without aura in adult patients: An unexpected finding.

BACKGROUND: Altered sensory processing in migraine has been demonstrated by several studies in unimodal, and especially visual, tasks. While there is some limited evidence hinting at potential alterations in multisensory processing among migraine sufferers, this aspect remains relatively unexplored. This study investigated the interictal cognitive performance of migraine patients without aura compared to matched controls, focusing on associative learning, recall, and transfer abilities through the Sound-Face Test, an audiovisual test based on the principles of the Rutgers Acquired Equivalence Test. MATERIALS AND METHODS: The performance of 42 volunteering migraine patients was compared to the data of 42 matched controls, selected from a database of healthy volunteers who had taken the test earlier. The study aimed to compare the groups' performance in learning, recall, and the ability to transfer learned associations. RESULTS: Migraine patients demonstrated significantly superior associative learning as compared to controls, requiring fewer trials, and making fewer errors during the acquisition phase. However, no significant differences were observed in retrieval error ratios, generalization error ratios, or reaction times between migraine patients and controls in later stages of the test. CONCLUSION: The results of our study support those of previous investigations, which concluded that multisensory processing exhibits a unique pattern in migraine. The specific finding that associative audiovisual pair learning is more effective in adult migraine patients than in matched controls is unexpected. If the phenomenon is not an artifact, it may be assumed to be a combined result of the hypersensitivity present in migraine and the sensory threshold-lowering effect of multisensory integration.

The effectiveness of agomelatine on headache severity and frequency in episodic migraine without aura; a parallel randomized controlled trial study.

BACKGROUND: Migraine is a headache disorder that affects public health and reduces the patient's quality of life. Preventive medication is necessary to prevent acute attacks and medication overuse headaches (MOH). Agomelatine is a melatonin antagonist. AIMS: This study aimed to determine the effectiveness of agomelatine on the severity and frequency of migraine attacks. METHODS: The study is a parallel randomized controlled trial with two groups of intervention and control. 400 patients were evaluated. Eligible individuals, including those with episodic migraine headaches without aura between the ages of 18 and 60 years who did not receive preventive treatment beforehand, were enrolled. Also, patients did not receive any specific medications for other diseases. Among these, 100 people met the inclusion criteria and entered the study. These subjects were randomly assigned to one of the two groups. The intervention group received 25 mg of agomelatine daily and the control group received B1. In this study, the effect of agomelatine on the frequency and severity of attacks, mean monthly migraine days (MMD), and migraine disability assessment (MIDAS), were assessed. The study was triple-blind and after three months, a post-test was performed. Data were analyzed using SPSS software. RESULTS: A total of 100 patients were randomly assigned to either intervention or control groups. The prescriber physician and the data collector did not know about the allocation of patients to groups. Before the intervention, there was no significant difference in the headache frequency per month (t=-0.182, df = 98, p = 0.85), mean MMD (p = 0.17), headache severity (p = 0.076), and MIDAS (p = 0.091). After the study, there was a significant difference between the two groups in terms of the headache frequency per month (p = 0.009), and mean of MMD (p = 0.025). There was also a significant difference between pretest and posttest in two groups in the headache severity (p < 0.001) and MIDAS (p < 0.001). CONCLUSION: Agomelatine can be used as a preventive medication for migraine without aura. It is suggested that agomelatine be studied in comparison with other preventive drugs for patients with migraine. TRIAL RETROSPECTIVELY REGISTRATION: Trial Retrospectively registration= IRCT20230303057599N1. Date: 2023-5-24 The present study is a residency thesis approved by the Tehran University of Medical Sciences.

Investigating the causal association between systemic lupus erythematosus and migraine using Mendelian randomization analysis.

OBJECTIVE: To assess whether systemic lupus erythematosus (SLE) may be genetically causally associated with migraine, including the two primary subtypes: migraine with aura (MWA) and migraine without aura (MWoA). BACKGROUND: The association between SLE and migraine has been investigated extensively. Previous studies have shown a higher prevalence of migraine in patients with SLE, although the exact relationship remains unclear. This study investigated the potential causal association between SLE and migraine using the powerful analytical tool of Mendelian randomization (MR). METHODS: We performed two-sample MR analysis of publicly available summary statistic datasets using inverse variance-weighted (IVW), weighted median, and MR-Egger methods based on an SLE genome-wide association study (GWAS; 5201 cases; 9066 controls; the exposure frequency is 36.5%) as an exposure and migraine GWAS (15,905 cases; 264,662 controls) in individuals with European ancestry as outcomes, focusing on the two migraine subtypes MWA (6780 cases; 264,662 controls) and MWoA (5787 cases; 264,662 controls). Thepleiotropy and heterogeneity were performed. RESULTS: We selected 42 single-nucleotide polymorphisms from SLE GWAS as instrumental variables (IVs) for SLE on migraine, and 41 SNP IVs for SLE on MWA or MWoA. The IVW (odds ratio [OR] = 1.01, 95% confidence interval [CI] = [0.99, 1.03], p = 0.271), weighted median (OR = 1.00, 95% CI = [0.97, 1.03], p = 0.914), and MR-Egger (OR = 1.04, 95% CI = [0.99, 1.09], p = 0.153) methods showed no causal effect of SLE on migraine. A causal effect of SLE was observed on MWA (IVW: OR = 1.05, 95% CI = [1.02, 1.08], p = 0.001; weighted median: OR = 1.05, 95% CI = [1.01, 1.10], p = 0.018; MR-Egger: OR = 1.07, 95% CI = [1.01, 1.14], p = 0.035 and pIVW < 0.017 [Bonferroni correction]) but not MWoA (IVW: OR = 0.99, 95% CI = [0.96, 1.02], p = 0.331; weighted median: OR = 0.98, 95% CI = [0.94, 1.03], p = 0.496; MR-Egger: OR = 1.02, 95% CI = [0.95, 1.09], p = 0.652). The results showed no significant pleiotropy or heterogeneity. CONCLUSION: Our MR analysis demonstrated the complex relationship between SLE and migraine, suggesting a potential effect of SLE on the risk of MWA but not MWoA. These findings can aid in the development of improved subtype-specific management of migraine in patients with SLE.

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.

Altered Neuromagnetic Activity in the Default Mode Network in Migraine and Its Subgroups (Episodic Migraine and Chronic Migraine).

BACKGROUND: The differences in the resting state spectral power and functional connectivity of the default mode network between people with migraine without aura (MwoA) and its subgroups differentiated by frequency (episodic migraine (EM) and chronic migraine (CM)) and healthy controls (HC) were investigated using magnetoencephalography. METHODS: In the resting state, the topological spatial structure of the brain in 33 MwoA patients and 22 HC was first studied using magnetoencephalography, followed by probing the neuroelectrical activity of 17 CM and 16 EM patients, to identify damage to their default mode network (DMN). The techniques used to investigate both spectral power and functional connectivity were minimum-paradigm estimation combined with Welch's technique and corrected amplitude envelope correlation. RESULTS: The differences between MwoA and its subgroups (CM and EM) and HC based on spectral power were mainly in the delta, theta, and alpha bands, while the differences in functional connectivity were primarily in the delta, alpha, and beta bands. In the delta and theta bands, the spectral power of MwoA and its subgroups (CM and EM) was higher than in the HC group. The spectral power of MwoA and its subgroups (CM and EM) was lower in the alpha band. In terms of functional connectivity, the corrected amplitude envelope correlation of MwoA and its subgroups (CM and EM) was lower than the HC group in the bands with spectral differences. People with EM and CM differed in the spectral power in the left medial prefrontal cortex and the right lateral temporal cortex in the alpha band, where correlation analysis and logistic regression analysis showed that the intensity of the spectral power of the left medial prefrontal cortex was negatively correlated with headache frequency. CONCLUSIONS: The spectral power of the left medial prefrontal cortex in the alpha band may serve as a biomarker that is associated with the number of monthly headache attacks and may be a potential neuromodulatory target for controlling migraine chronicity.

Migraine with and without aura in relation to the menstrual cycle and other hormonal milestones: A prospective cohort study.

BACKGROUND: Previous studies showed that the perimenstrual window is associated with an increased susceptibility to migraine attacks without aura, but had conflicting results regarding attacks with aura. METHODS: We performed a longitudinal E-diary study among 526 premenopausal women with migraine. Differences in occurrence of perimenstrual migraine attacks between women with migraine with aura and without aura were assessed using a mixed effects logistic regression model. Additionally, participants completed a questionnaire about the influence of hormonal milestones on migraine frequency. RESULTS: Prevalence of menstrual migraine did not differ between women with migraine without aura and migraine with aura (59% versus 53%, p = 0.176). The increased risk of migraine attacks without aura during the perimenstrual window was similar for women with migraine without aura (OR[95%CI]:1.53 [1.44-1.62]) and those with migraine with aura (1.53 [1.44-1.62]). The perimenstrual window was not associated with increased risk of migraine aura attacks (1.08 [0.93-1.26], p = 0.314). Women with migraine with aura more often reported increased migraine frequency during pregnancy and breastfeeding compared to women with migraine without aura, but not during hormonal contraception use. CONCLUSION: Sex hormone levels seem to differently affect the trigeminovascular system (migraine headache) and the susceptibility to cortical spreading depolarization (aura). Exclusively migraine attacks without aura should be interpreted as perimenstrual attacks.

Evaluation of the ICHD-3 diagnostic criteria for cardiac cephalalgia and new proposal.

BACKGROUND: The current International Classification of Headache Disorders, 3rd edition (ICHD-3) diagnostic criteria for cardiac cephalalgia were established according to previous case reports and the opinion of experts. We aimed to assess the ICHD-3 diagnostic criteria for cardiac cephalalgia. METHODS: We conducted a series of cases study and evaluated these criteria in 54 patients with cardiac cephalalgia. Next, we assessed whether the ICHD-3 diagnostic criteria B, C and D for migraine without aura were fulfilled by these patients. RESULTS: ICHD-3 criteria A, B, C1, C2 and D for cardiac cephalalgia were met by 100% of patients, whereas criterion C3 was fulfilled by 81.5%. The least frequently fulfilled sub-criterion was C3b (accompanied by nausea) (18.5%). Moreover, we found that ICHD-3 criteria B, C and D for migraine without aura were met by a low proportion of patients: 11.1%, 46.3% and 25.9%, respectively, and no patient fulfilled the three criteria simultaneously. CONCLUSION: Based on our results, we propose revised diagnostic criteria for cardiac cephalalgia. We suggest removing criterion C3 and C4. We also suggest removing the word "migraine-like" from its description.

Lack of reproducibility of resting-state functional MRI findings in migraine with aura.

BACKGROUND: Several studies have applied resting-state functional MRI to examine whether functional brain connectivity is altered in migraine with aura patients. These studies had multiple limitations, including small sample sizes, and reported conflicting results. Here, we performed a large, cross-sectional brain imaging study to reproduce previous findings. METHODS: We recruited women aged 30-60 years from the nationwide Danish Twin Registry. Resting-state functional MRI of women with migraine with aura, their co-twins, and unrelated migraine-free twins was performed at a single centre. We carried out an extensive series of brain connectivity data analyses. Patients were compared to migraine-free controls and to co-twins. RESULTS: Comparisons were based on data from 160 patients, 30 co-twins, and 136 controls. Patients were similar to controls with regard to age, and several lifestyle characteristics. We replicated clear effects of age on resting-state networks. In contrast, we failed to detect any differences, and to replicate previously reported differences, in functional connectivity between migraine patients with aura and non-migraine controls or their co-twins in any of the analyses. CONCLUSION: Given the large sample size and the unbiased population-based design of our study, we conclude that women with migraine with aura have normal resting-state brain connectivity outside of migraine attacks.

Sex differences in clinical characteristics of migraine and its burden: a population-based study.

BACKGROUND AND PURPOSE: Understanding migraine in a sex-specific manner is crucial for improving clinical care, diagnosis and therapy for both females and males. Here, data on sex differences are provided in the presentation of migraine in a large European-based population cohort, which is representative of the general population. METHODS: A population-based study of 62,672 Danish blood donors (both present and previous donors), of whom 12,658 had migraine, was performed. All participants completed a 105-item diagnostic migraine questionnaire sent via an electronic mailing system (e-Boks) between May 2020 and August 2020. The questionnaire allowed for correct diagnosis of migraine according to the International Classification of Headache Disorders, third edition. RESULTS: The migraine questionnaire was in-cohort validated and had a positive predictive value of 97% for any migraine, a specificity of 93% and a sensitivity of 93%. There were 9184 females (mean age 45.1 years) and 3434 males (mean age 48.0 years). The 3-month prevalence of migraine without aura was 11% in females and 3.59% in males. The 3-month prevalence of migraine with aura was 1.72% in females and 1.58% in males. In females, the age-related 3-month prevalence of migraine without aura increased markedly during childbearing age. In males, migraine both with and without aura showed less age variation. Females had a higher frequency of migraine attacks (odds ratio [OR] 1.22) but a lower frequency of non-migraine headaches (OR = 0.35). Females also had a greater intensity of pain, more unilateral and pulsatile pain, and exacerbation by physical activity (OR = 1.40-1.49) as well as more associated symptoms (OR = 1.26-1.98). Females carried 79% of the total migraine disease burden, which was almost exclusively driven by migraine without aura (77%), whilst there was no sex difference in the disease burden of migraine with aura. CONCLUSION: Females have more severe disease, resulting in a much higher migraine disease burden than indicated by prevalence alone.

Visual temporal discrimination is impaired in patients with migraine without aura.

BACKGROUND AND OBJECTIVE: Dysfunctional sensory processing is described in migraine. This study aimed to evaluate visual perception in patients with migraine without aura using the visual temporal discrimination (VTD) test. METHODS: A total of 45 participants were enrolled in this prospective exploratory study. In all, 15 patients had migraine without aura and 15 healthy volunteers were analyzed in the study. The VTD threshold (VTDT) was measured using light-emitting diode lights to perceive two separate visual stimuli as clearly distinct. VTD was tested during the attack and the interictal period. The disease duration, attack side, visual analog scale for pain, accompanying symptoms, and allodynia were recorded during the attack. RESULTS: The VTDT of each visual field in both attack (mean [SD] 102.3 [38.4] ms for the right visual field and 106.3 [52.2] ms for the left) and the interictal periods (mean [SD] 75.2 [27.9] ms for the right and 78.2 [27.9] ms for the left) were significantly higher than in the control group (mean [SD] 45.3 [9.9] ms for the right and 48.2 [11.9] ms for the left) (p < 0.001, p < 0.001, p = 0.003, p < 0.001, respectively). The ipsilateral threshold during the attack was significantly prolonged compared to the interictal period (mean [SD] 143.8 [53.8] vs. 78 [19.6] ms, p = 0.025) and the contralateral threshold during the attack (mean [SD] 143.8 [53.8] vs. 71.9 [14.1] ms, p = 0.025). The ipsilateral threshold was significantly correlated with the visual analog score (r = 0.894, p < 0.001) and frequency of the attacks (r = 0.696, p = 0.004), but not correlated with photophobia. CONCLUSION: The VTDTs are prolonged both ictally and interictally in patients with migraine without aura attacks. Ipsilateral threshold prolongation is more pronounced during lateralized migraine attacks. The results suggest dysfunctional visual perception is not limited to the migraine attack period, and a defective sensory processing/modulation in the visual pathways may involve the superior colliculus.

Altered resting-state effective connectivity of trigeminal vascular system in migraine without aura: A spectral dynamic causal modeling study.

BACKGROUND: The trigeminal vascular system is an important part of the anatomical and physiological basis of migraine. The effective connectivity (EC) among the regions of interest (ROIs) in the trigeminal vascular system involved in migraine without aura (MWoA) remains unclear. METHODS: In this cross-sectional study, 48 patients (mean [SD] age 38.06 [10.35] years; male, 14/48 [29%]) with MWoA during the interictal phase and 48 healthy controls of similar age and sex (mean [SD] age 38.96 [10.96] years; male, 14/48 [29%]) underwent resting-state functional magnetic resonance imaging (fMRI). Dynamic causal modeling analysis was conducted to investigate directional EC among ROIs in the trigeminal vascular system including the bilateral brainstem, the primary somatosensory cortex (S1), the thalamus, and the insula. RESULTS: Compared with the healthy control group, MWoA represented significantly reduced EC from the left brainstem (Brainstem.L) to the left insula (MWoA: mean [SD] -0.16 [0.36]; healthy controls: mean [SD] 0.11 [0.41]; Pcorrected = 0.021), reduced EC from the Brainstem.L to the right insula (MWoA: mean [SD] -0.15 [0.39]; healthy controls: mean [SD] 0.03 [0.35]; Pcorrected = 0.021), and decreased EC from the left thalamus (Thalamus.L) to the Brainstem.L (MWoA: mean [SD] -0.13 [0.56]; healthy controls: mean [SD] 0.10 [0.45]; Pcorrected = 0.021). Altered EC parameters were not significantly correlated with MWoA clinical data. CONCLUSION: These results further provide increasing evidence that disturbed homeostasis of the trigeminovascular nociceptive pathway is involved in the pathophysiological mechanisms of migraine. Patients with MWoA exhibited a regional interaction distinct from healthy controls in the neural pathway of the Bilateral Insula-Brainstem.L-Thalamus.L, which may shed light on the future understanding of brain mechanisms for MWoA. Future brain-based interventions are suggested to consider the dysregulation in the Bilateral Insula-Brainstem.L-Thalamus.L circuits.

Resting-state electroencephalography microstate dynamics altered in patients with migraine with and without aura-A pilot study.

OBJECTIVE: To evaluate electroencephalography (EEG) microstate differences between patients with migraine with aura (MWA), patients with migraine without aura (MWoA), and healthy controls (HC). BACKGROUND: Previous research employing microstate analysis found unique microstate alterations in patients with MWoA; however, it is uncertain how microstates appear in patients with MWA. METHODS: This study was conducted at the Headache Clinic of the First Affiliated Hospital of Xi'an Jiaotong University. In total, 30 patients with MWA, 30 with MWoA, and 30 HC were enrolled in this cross-sectional study. An EEG was recorded for all participants under resting state. The microstate parameters of four widely recognized microstate classes A-D were calculated and compared across the three groups. RESULTS: The occurrence of microstate B (MsB) in the MWoA group was significantly higher than in the HC (p = 0.006, Cohen's d = 0.72) and MWA (p = 0.016, Cohen's d = 0.57) groups, while the contribution of MsB was significantly increased in the MWoA group compared to the HC group (p = 0.016, Cohen's d = 0.64). Microstate A (MsA) displayed a longer duration in the MWA group compared to the MWoA group (p = 0.007, Cohen's d = 0.69). Furthermore, the transition probability between MsB and microstate D was significantly increased in the MWoA group compared to the HC group (p = 0.009, Cohen's d = 0.68 for B to D; p = 0.007, Cohen's d = 0.71 for D to B). Finally, the occurrence and contribution of MsB were positively related to headache characteristics in the MWoA group but negatively in the MWA group, whereas the duration of MsA was positively related to the visual analog scale in the MWA group (all p < 0.05). CONCLUSIONS: Patients with MWA and MWoA have altered microstate dynamics, indicating that resting-state brain network disorders may play a role in migraine pathogenesis. Microstate parameters may have the potential to aid clinical management, which needs to be investigated further.

Migraine, inflammatory bowel disease and celiac disease: A Mendelian randomization study.

OBJECTIVE: To assess whether migraine may be genetically and/or causally associated with inflammatory bowel disease (IBD) or celiac disease. BACKGROUND: Migraine has been linked to IBD and celiac disease in observational studies, but whether this link may be explained by a shared genetic basis or could be causal has not been established. The presence of a causal association could be clinically relevant, as treating one of these medical conditions might mitigate the symptoms of a causally linked condition. METHODS: Linkage disequilibrium score regression and two-sample bidirectional Mendelian randomization analyses were performed using summary statistics from cohort-based genome-wide association studies of migraine (59,674 cases; 316,078 controls), IBD (25,042 cases; 34,915 controls) and celiac disease (11,812 or 4533 cases; 11,837 or 10,750 controls). Migraine with and without aura were analyzed separately, as were the two IBD subtypes Crohn's disease and ulcerative colitis. Positive control analyses and conventional Mendelian randomization sensitivity analyses were performed. RESULTS: Migraine was not genetically correlated with IBD or celiac disease. No evidence was observed for IBD (odds ratio [OR] 1.00, 95% confidence interval [CI] 0.99-1.02, p = 0.703) or celiac disease (OR 1.00, 95% CI 0.99-1.02, p = 0.912) causing migraine or migraine causing either IBD (OR 1.08, 95% CI 0.96-1.22, p = 0.181) or celiac disease (OR 1.08, 95% CI 0.79-1.48, p = 0.614) when all participants with migraine were analyzed jointly. There was some indication of a causal association between celiac disease and migraine with aura (OR 1.04, 95% CI 1.00-1.08, p = 0.045), between celiac disease and migraine without aura (OR 0.95, 95% CI 0.92-0.99, p = 0.006), as well as between migraine without aura and ulcerative colitis (OR 1.15, 95% CI 1.02-1.29, p = 0.025). However, the results were not significant after multiple testing correction. CONCLUSIONS: We found no evidence of a shared genetic basis or of a causal association between migraine and either IBD or celiac disease, although we obtained some indications of causal associations with migraine subtypes.

Should migraine without aura be further divided? A study of 1444 female patients with migraine without aura.

To explore the possibility of further dividing migraine without aura (MWA), 1444 female patients fulfilled the criterion were recruited, and grouped basing on the association of MWA onset with menarche and childbirth (group J1, onset before menarche; group J2, onset between menarche and childbirth; group J3, onset after childbirth). By comparing migraine (side, location, aggravated by routine physical activity, NRS score, frequency, accompanying symptoms, with premonitory symptom (PS) and trigger, sum of PS and trigger) and migraine-related factors [chronic daily headache, medicine overused headache, body mass index (BMI), education level, exercise status, sleep status, consumption of tea/coffee/alcohol, patient health questionnaire-9 (PHQ-9) score and generalized anxiety disorder-7, (GAD-7) score)] among groups, it was found that the J1 group and the J2 group presented more typical migraine features than the J3 group; 2) the J3 group was more prone to emotion and sleep disorders, weight management issues, frequent migraine attacks and medication overuse. This study provided a basis for further dividing MWA. Genetic research should be conducted and treatment should be prescribed accordingly because the underlying pathogenesis may be different.

Parahippocampus hypertrophy drives gray matter morphological alterations in migraine patients without aura.

BACKGROUND: The aberrance of gray matter morphology in migraineurs has been widely investigated. However, it remains largely unknown whether there are illness duration-related hierarchical changes in the gray matter structure. METHODS: A total of 86 migraine without aura (MwoA) patients and 73 healthy controls were included. The Voxel-Based Morphometry approach was utilized to compare the gray matter volume (GMV) differences between MwoA patients and healthy controls. The Structural Covariance Network analysis was conducted to quantify the cross-regional synchronous alterations of gray matter structure in MwoA patients. The Causal Structural Covariance Network analysis was performed to describe the progressive and hierarchical changes in the gray matter network of patients in the pathological progression of migraine. RESULTS: MwoA patients had duration-stage related GMV hypertrophy in the left parahippocampus, as well as synergistic GMV aberrance in the parahippocampus and the medial inferior temporal gyrus and cerebellum. Moreover, the GMV alteration of the parahippocampus, and the surrounding hippocampus, amygdala, and bilateral anterior cerebellum, preceded and causally influenced the morphological changes of lateral parietal-temporal-occipital gyrus, as well as the motor cortex and prefrontal gyrus with the increasing illness duration in MwoA patients. CONCLUSION: The current study indicated that gray matter structural alterations in the medial inferior temporal gyrus, especially the parahippocampus, is a critical pathological characteristic in MwoA patients, which drives the gray matter structure alteration of other regions. These findings provide further evidence for understanding the progressive gray matter morphological changes in migraine and may facilitate the development of neuromodulation therapies targeting this procession.

Arterial spin labeling MRI applied to migraine: current insights and future perspectives.

INTRODUCTION: Advanced neuroimaging techniques have extensively contributed to elucidate the complex mechanisms underpinning the pathophysiology of migraine, a neurovascular disorder characterized by episodes of headache associated with a constellation of non-pain symptoms. The present manuscript, summarizing the most recent progresses of the arterial spin labelling (ASL) MRI techniques and the most significant findings from ASL studies conducted in migraine, is aimed to clarify how ASL investigations are contributing to the evolving insight on migraine pathophysiology and their putative role in migraine clinical setting. ASL techniques, allowing to quantitatively demonstrate changes in cerebral blood flow (CBF) both during the attacks and in the course of interictal period, could represent the melting point between advanced neuroimaging investigations, conducted with pure scientific purposes, and conventional neuroimaging approaches, employed in the diagnostic decision-making processes. MAIN BODY: Converging ASL evidences have demonstrated that abnormal CBF, exceeding the boundaries of a single vascular territory, with biphasic trend dominated by an initial hypoperfusion (during the aura phenomenon but also in the first part of the headache phase) followed by hyperperfusion, characterizes migraine with aura attack and can represent a valuable clinical tool in the differential diagnosis from acute ischemic strokes and epileptic seizures. Studies conducted during migraine without aura attacks are converging to highlight the involvement of dorsolateral pons and hypothalamus in migraine pathophysiology, albeit not able to disentangle their role as "migraine generators" from mere attack epiphenomenon. Furthermore, ASL findings tend to support the presence of perfusion abnormalities in brain regions known to be involved in aura ignition and propagation as well as in areas involved in multisensory processing, in both patients with migraine with aura and migraine without aura. CONCLUSION: Although ASL studies have dramatically clarified quality and timing of perfusion abnormalities during migraine with aura attacks, the same cannot be said for perfusion changes during migraine attacks without aura and interictal periods. Future studies with more rigorous methodological approaches in terms of study protocol, ASL technique and sample selection and size are mandatory to exploit the possibility of better understanding migraine pathophysiology and identifying neuroimaging biomarkers of each migraine phase in different migraine phenotypes.