Genetics of migraine

Female-specific risk variables: From innocent bystanders to key players in cardiovascular risk prediction

There is an increasing interest among professionals in cardiovascular medicine in women-specific risk variables related to gynecologic conditions over the life span. Although adverse lifestyle factors, hypertension, dyslipidemia and insulin resistance are recognized as the most important risk factors in older women, there is still uncertainty over how to account for other risk variables. For instance, migraine from puberty onwards, chronic inflammatory conditions and mental stress affect cardiovascular risk in women. As prevention should start as early in life as possible, appropriate risk estimation in women at middle age is crucial. In case of doubt, a coronary artery calcium score with a computed tomography scan at a radiology department can be helpful to discriminate between low and high risk for an individual. This may also pave the way for safe menopausal hormone therapy if needed. In this paper we summarize the current status of women-specific and other relevant risk variables from the perspective of the cardiologist.

Risk of major mental disorders in the offspring of parents with migraine

BACKGROUND

Migraine has been associated with mental disorders, however whether parental migraine is associated with an increased risk of major mental disorders (MMDs) in offspring has not been investigated. We aimed to examine the risk of the development of MMDs in the offspring of parents with migraine compared with those of parents without migraine.

METHODS

This study used data derived from the Taiwan National Health Insurance Research Database. Offspring of parents with migraine and a control group consisting of offspring of parents without migraine matched for demographic and parental mental disorders were included. Cox regression was used to estimate the risk of MMDs, including schizophrenia, depressive disorder, bipolar disorder, autistic spectrum disorder (ASD), and attention deficit/hyperactivity disorder (ADHD). Sub-analyses stratified by the fathers and mothers were further performed to separately clarify the risks of MMDs among the offspring.

RESULTS

We included 22,747 offspring of parents with migraine and 227,470 offspring of parents without migraine as the controls. Parental migraine was significantly associated with an increased risk of ADHD (reported as hazard ratios with 95% confidence intervals: 1.37, 1.25-1.50), bipolar disorder (1.35, 1.06-1.71), and depressive disorder (1.33, 1.21-1.47) compared to the offspring of parents without migraine. Importantly, sub-analyses showed that only maternal migraine was significantly associated with these risks.

CONCLUSIONS

Due to the heavy burden of MMDs, healthcare workers should be aware of the risk of MMDs in the offspring of parents with migraine, particular in mothers.

Approach to the Diagnosis and Treatment of Headache

Headache is consistently one of the most common complaints reported by patients in the medical setting worldwide. Headache can be a symptom of another condition or illness, secondary to the disruption of homeostasis, or can be a primary disorder with inherent variability and patterns. Headache disorders, whether primary or secondary, can cause significant disability and loss of quality of life for those affected. As such, it is important for primary care providers to feel confident evaluating and treating patients with headache, especially given the limited access to Headache Medicine subspecialists.

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.

Silent brain infarct in migraine: Systematic review and meta-analysis

BACKGROUND

While migraine, particularly migraine with aura, is a recognized risk factor for ischemic stroke, the association of migraine with silent brain infarction is a matter of debate, as studies on this topic have yielded conflicting results.

METHODS

A systematic review of the literature was conducted of studies reporting migraine and silent brain infarction, assessed by magnetic resonance imaging, between January 1980 and April 2022, by consulting Medline and Embase databases. Studies with a control group were included in a meta-analysis of population-based studies. An exploratory meta-analysis of both population-based and clinical-based studies was further performed to test the association between migraine with aura and silent brain infarction.

RESULTS

A total of 2,408 articles were identified, among which 24 were included in the systematic review and 10 in the meta-analysis. The meta-analysis of population-based studies showed no association of migraine with silent brain infarction (odds ratio (OR)=1.32 [95% CI 0.92;1.90], P=0.13) and migraine with aura with silent brain infarction (OR=1.56 [0.74;3.30], P=0.24). However, in the exploratory meta-analysis of population-based and clinical-based studies, migraine with aura was significantly associated with silent brain infarction (OR=1.91 [1.02;3.59], P=0.04) and to silent cerebellar infarcts (OR=2.57 [1.01;6.56], P=0.05).

CONCLUSION

In this updated systematic review and meta-analysis of population-based studies, migraine and migraine with aura were not associated with silent brain infarction.

Migraine - a borderland disease to epilepsy: near it but not of it

BACKGROUND

Migraine and epilepsy are two paroxysmal chronic neurological disorders affecting a high number of individuals and being responsible for a high individual and socioeconomic burden. The link between these disorders has been of interest for decades and innovations concerning diagnosing and treatment enable new insights into their relationship.

FINDINGS

Although appearing to be distinct at first glance, both diseases exhibit a noteworthy comorbidity, shared pathophysiological pathways, and significant overlaps in characteristics like clinical manifestation or prophylactic treatment. This review aims to explore the intricate relationship between these two conditions, shedding light on shared pathophysiological foundations, genetic interdependencies, common and distinct clinical features, clinically overlapping syndromes, and therapeutic similarities. There are several shared pathophysiological mechanisms, like CSD, the likely underlying cause of migraine aura, or neurotransmitters, mainly Glutamate and GABA, which represent important roles in triggering migraine attacks and seizures. The genetic interrelations between the two disorders can be observed by taking a closer look at the group of familial hemiplegic migraines, which are caused by mutations in genes like CACNA1A, ATP1A2, or SCN1A. The intricate relationship is further underlined by the high number of shared clinical features, which can be observed over the entire course of migraine attacks and epileptic seizures. While the variety of the clinical manifestation of an epileptic seizure is naturally higher than that of a migraine attack, a distinction can indeed be difficult in some cases, e.g. in occipital lobe epilepsy. Moreover, triggering factors like sleep deprivation or alcohol consumption play an important role in both diseases. In the period after the seizure or migraine attack, symptoms like speech difficulties, tiredness, and yawning occur. While the actual attack of the disease usually lasts for a limited time, research indicates that individuals suffering from migraine and/or epilepsy are highly affected in their daily life, especially regarding cognitive and social aspects, a burden that is even worsened using antiseizure medication. This medication allows us to reveal further connections, as certain antiepileptics are proven to have beneficial effects on the frequency and severity of migraine and have been used as a preventive drug for both diseases over many years.

CONCLUSION

Migraine and epilepsy show a high number of similarities in their mechanisms and clinical presentation. A deeper understanding of the intricate relationship will positively advance patient-oriented research and clinical work.

Association of Migraine and Blood Pressure-Does Obesity Severity Have a Moderating Role?

BACKGROUND

The relationship between migraine and blood pressure (BP) is equivocal, warranting exploration of potential moderators. Obesity associates with both migraine and BP in a dose-dependent fashion, although its role as a moderator has not been evaluated. We examined the relation between migraine and BP in women with comorbid migraine and obesity, and whether this relation was influenced by obesity severity.

METHODS

Women with migraine and obesity (n = 134) completed a 28-day headache diary before randomization to lifestyle intervention or migraine education. BP (systolic (SBP)/diastolic (DBP)), body mass index (BMI), and waist circumference (WC) were measured before diary completion. Hierarchical linear regression assessed associations between BP and migraine characteristics (headache frequency, duration, and pain intensity), and obesity severity (both total (BMI) and abdominal (WC)) as moderators of these associations.

RESULTS

Participants (BMI = 35.4 ± 6.5 kg/m2; WC = 105.4 ± 15.6 cm, SBP = 113.1 ± 12.1/DPB = 68.1 ± 8.0 mmHg) reported 8.4 ± 4.5 migraine days that lasted 20.2 ± 15.9 h with mean pain intensity of 5.9 ± 1.6 on a 10-point scale. DBP inversely related to migraine days in both total (β =  - 0.226, p = .010) and abdominal (β = 0.214, p = .015) obesity severity models. SBP and obesity severity did not relate to migraine characteristics. Obesity severity did not moderate relations between migraine characteristics and BP (p's > .05).

CONCLUSION

Among women with comorbid migraine and obesity, DBP inversely related to migraine frequency; however, obesity severity did not affect the strength of this or other examined associations. Future studies including healthy weight controls and men and women with continuous BP measures are needed to confirm these findings and identify mechanisms and moderators.

Genetic Variability in Vitamin D Receptor and Migraine Susceptibility: A Southeastern European Case-Control Study

Migraine is a common primary headache disorder with both environmental and genetic inputs. Cumulative evidence indicates an association between vitamin D and headache. Unravelling the precise role of vitamin D and its receptor in the pathophysiology of migraine can eventually contribute to more efficient prevention and management of this headache disorder. The aim of the study was to investigate the relation of the three most studied VDR variants, i.e., FokI (rs2228570), TaqI (rs731236) and BsmI (rs1544410), with migraine susceptibility and distinct clinical phenotypes in a Southeastern European case-control population residing in Greece. DNA was extracted from 191 unrelated patients diagnosed with migraine and 265 headache-free controls and genotyped using real-time PCR (LightSNiP assays) followed by melting curve analysis. Genotype frequency distribution analysis of the TaqI and BsmI variants showed a statistically significant difference between migraine cases and controls. In addition, subgroup analyses revealed a significant association between all three studied VDR variants, particularly with a migraine without aura subtype. Therefore, the current study provides supporting evidence for a possible association of VDR variants with migraines, particularly migraine without aura susceptibility in Southeastern Europeans residing in Greece, further reinforcing the emerging role of vitamin D and its receptor in migraines.

Melkersson-Rosenthal Syndrome and Migraine: A New Phenotype Associated with SCN1A Variants?

Peripheral facial palsy rarely occurs as part of Melkersson-Rosenthal syndrome (MRS), which is characterized by the classical triad of tongue cheilitis, recurrent episodes of orofacial swelling, and palsy. MRS is a disorder with variable expressivity and clinical as well as genetic heterogeneity; however, the causative gene remains to be identified. Migraine is a common neurological disorder, presenting with or without aura, which may be associated with neurological symptoms. The classical example of monogenic migraine is familial hemiplegic migraine (FHM), which has phenotypic variability in carriers of variants in the same gene or even carriers of the same variant. We present a family in which two sisters displayed recurrent migraines, one of which presented recurrent facial palsy and had clinical diagnosis of MRS. We performed WES and Sanger sequencing for segregation analysis in the available family members. We identified a c.3521C>G missense heterozygous variant in SCN1A carried only by the affected sister. Variants in the SCN1A gene can cause a spectrum of early-onset epileptic encephalopathies, in addition to FHM; therefore, our finding reasonably explains the proband phenotype, in which the main symptom was recurrent facial palsy. This report also adds knowledge to the clinical spectrum of SCN1A alterations and suggests a potential overlap between MRS and FHM.

Association between selenium intake and migraine: a nationwide cross-sectional study

Background

Dietary interventions for migraine are receiving increasing attention. However, it remains unclear whether there is any relationship between migraine and selenium intake. The aim of this study was to investigate the association between selenium intake and migraine.

Methods

We used multivariate logistic regression equations to explore the association between selenium intake and migraine. Restricted cubic splines were used to examine the presence of non-linear relationships. Upon finding a non-linear relationship, a recursive algorithm was used to calculate the inflection point. Population differences were also explored through stratified analysis.

Results

In the model adjusted for all covariates, the ORs (95% CI) for the association between selenium intake and migraine were 0.96 (0.88, 1.04), which was no statistical significance. However, the result of the linear trend test with quadrilles of selenium intake indicated the association between selenium intake and migraine may be non-linear. The restricted cubic splines confirmed this non-linear relationship, finding an inflection point (93.1 mcg/day), where the odds of migraine decreased with increasing selenium intake before the inflection point, and no statistically significant relationship was found after the inflection point. The association between selenium intake and migraine was non-linear in all strata except the obese.

Conclusion

We found a non-linear association between selenium intake and migraine in the general American population.

Primary headache disorders: From pathophysiology to neurostimulation therapies

Primary headache disorders including migraine, cluster headache, and tension-type headache are among the most common disabling diseases worldwide. The unclear pathogenesis of primary headache disorders has led to high rates of misdiagnosis and limited available treatment options. In this review, we have summarized the pathophysiological factors for a better understanding of primary headache disorders. Advances in functional neuroimaging, genetics, neurophysiology have indicated that cortical hyperexcitability, regional brain dysfunction, central sensitization and neuroplasticity changes play vital roles in the development of primary headache disorders. Moreover, we have also discussed a series of neurostimulation approaches with their stimulation mechanism, safety and efficacy for prevention and treatment of primary headache disorders. Noninvasive or implantable neurostimulation techniques show great promise for treating refractory primary headache disorders.

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.

Genetics of migraine: where are we now?

Migraine is a complex brain disorder explained by the interaction of genetic and environmental factors. In monogenic migraines, including familial hemiplegic migraine and migraine with aura associated with hereditary small-vessel disorders, the identified genes code for proteins expressed in neurons, glial cells, or vessels, all of which increase susceptibility to cortical spreading depression. The study of monogenic migraines has shown that the neurovascular unit plays a prominent role in migraine. Genome-wide association studies have identified numerous susceptibility variants that each result in only a small increase in overall migraine risk. The more than 180 known variants belong to several complex networks of "pro-migraine" molecular abnormalities, which are mainly neuronal or vascular. Genetics has also highlighted the importance of shared genetic factors between migraine and its major co-morbidities, including depression and high blood pressure. Further studies are still needed to map all of the susceptibility loci for migraine and then to understand how these genomic variants lead to migraine cell phenotypes.

Variability in oxidative stress-related genes (SOD2, CAT, GPX1, GSTP1, NOS3, NFE2L2, and UCP2) and susceptibility to migraine clinical phenotypes and features

Introduction

Migraine is a complex disorder with genetic and environmental inputs. Cumulative evidence implicates oxidative stress (OS) in migraine pathophysiology while genetic variability may influence an individuals' oxidative/antioxidant capacity. Aim of the current study was to investigate the impact of eight common OS-related genetic variants [rs4880 (SOD2), rs1001179 (CAT), rs1050450 (GPX1), rs1695 (GSTP1), rs1138272 (GSTP1), rs1799983 (NOS3), rs6721961 (NFE2L2), rs660339 (UCP2)] in migraine susceptibility and clinical features in a South-eastern European Caucasian population.

Methods

Genomic DNA samples from 221 unrelated migraineurs and 265 headache-free controls were genotyped for the selected genetic variants using real-time PCR (melting curve analysis).

Results

Although allelic and genotypic frequency distribution analysis did not support an association between migraine susceptibility and the examined variants in the overall population, subgroup analysis indicated significant correlation between NOS3 rs1799983 and migraine susceptibility in males. Furthermore, significant associations of CAT rs1001179 and GPX1 rs1050450 with disease age-at-onset and migraine attack duration, respectively, were revealed. Lastly, variability in the CAT, GSTP1 and UCP2 genes were associated with sleep/weather changes, alcohol consumption and physical exercise, respectively, as migraine triggers.

Discussion

Hence, the current findings possibly indicate an association of OS-related genetic variants with migraine susceptibility and clinical features, further supporting the involvement of OS and genetic susceptibility in migraine.

Understanding the link between obesity and headache- with focus on migraine and idiopathic intracranial hypertension

BACKGROUND

Obesity confers adverse effects to every system in the body including the central nervous system. Obesity is associated with both migraine and idiopathic intracranial hypertension (IIH). The mechanisms underlying the association between obesity and these headache diseases remain unclear.

METHODS

We conducted a narrative review of the evidence in both humans and rodents, for the putative mechanisms underlying the link between obesity, migraine and IIH.

RESULTS

Truncal adiposity, a key feature of obesity, is associated with increased migraine morbidity and disability through increased headache severity, frequency and more severe cutaneous allodynia. Obesity may also increase intracranial pressure and could contribute to headache morbidity in migraine and be causative in IIH headache. Weight loss can improve both migraine and IIH headache. Preclinical research highlights that obesity increases the sensitivity of the trigeminovascular system to noxious stimuli including inflammatory stimuli, but the underlying molecular mechanisms remain unelucidated.

CONCLUSIONS

This review highlights that at the epidemiological and clinical level, obesity increases morbidity in migraine and IIH headache, where weight loss can improve headache morbidity. However, further research is required to understand the molecular underpinnings of obesity related headache in order to generate novel treatments.