Health Behaviors and Social Determinants of Migraine in a Canadian Population‐Based Sample of Adults Aged 45‐85 Years: Findings From the CLSA

Physical activity as a predictor of fremanezumab response in chronic migraine - the Phy-Fre-Mig study

BACKGROUND

The relationship between physical activity (PA) and migraine is insufficiently understood. Studies have not analysed levels of PA or Time Sitting (TS) during preventive treatment, nor the role these might play in the response to preventive treatment.

METHODS

An observational, longitudinal prospective study in a headache clinic was conducted. All consecutive chronic migraine patients initiating fremanezumab were invited to participate and were followed for three visits. The International Physical Activity Questionnaire (IPAQ) - long version was used.

RESULTS

Seventy-six patients with a median of 46 years old, 84.2% female were enrolled. One month after fremanezumab administration, there was a significant increase of most PA variables and a significant decrease in TS levels compared with baseline; headache days and walking, TS and migraine days showed a moderate correlation. Three months after initiation, all PA variables statistically increased and TS levels statistically decreased, and variables such as headache/migraine days showed a moderate correlation with all PA variables analysed. In the multivariate analysis, higher levels of walking at baseline were independently associated with response to fremanezumab (ORa: 1.194; CI: 1.018-1.401, p = 0.029).

CONCLUSION

Patients who spent more time walking before starting treatment, were more likely to have a response to fremanezumab. PA and TS levels changed since the first month and correlated with clinical variables.

Prevalence of Neurologic Disease Among Those in Same-Sex Relationships: Evidence from the Medical Expenditure Panel Survey

Background and Objectives

Prior research has shown several health disparities affecting sexual minority people. Research on the neurologic health of sexual minority people has been limited. Our objective was to characterize the prevalence of neurologic disease and utilization of a neurologist among a population of sexual minority people.

Methods

We conducted a cross-sectional analysis of sexual minority people, using people in same-sex relationships as a proxy for sexual minority status, from the Medical Expenditure Panel Survey (MEPS) from 2016 to 2020. The MEPS is a government-run survey that uses complex sampling to obtain a nationally representative sample. Our primary outcome was a diagnosis of any neurologic disease. We also completed stratified analyses by sex, race, and ethnicity. Our secondary outcome was visit to a neurologist within the past year. Logistic regression was used to compare the odds of both outcomes in those in same-sex relationships and those in different-sex relationships.

Results

Among 153,313 MEPS participants, there were 61,645 (40.2%) participants in relationships who were included in our sample. Of those, 822 (1.33%) participants were in same-sex relationships. Participants were, on average, aged 51 years (median 50 years, IQR 38-63); nearly 50% reported female sex and mostly non-Hispanic White (67.81%). Among those in same-sex relationships, 22.7% reported a neurologic diagnosis compared with 18.1% of those in different-sex relationships (OR 1.33; 95% CI 1.04-1.71). This difference was maintained with adjustment for age, sex, education, and insurance (OR 1.48; 95% CI 1.15-1.91). There was no significant difference in visit to a neurologist (adjusted OR 1.38; 95% CI 0.91-2.10).

Discussion

In this nationally representative sample, neurologic disease was more prevalent among those in same-sex relationships compared with those in different-sex relationships. Limited sample size and absent measurements of minority stress limited the etiologic search for factors driving this disparity. There was no significant difference in visit to a neurologist, and both groups reported their overall health as being similar. There is a need for more routine measurement of sexual orientation in neurologic research. This will allow us to detail differences in neurologic disease risk factors, prevalence, and outcomes. The end goal is the identification of opportunities for intervention and advancement of neurologic health equity.

Exploring the genetic causal relationship between physical activity and migraine in European population based on Mendelian randomization analysis

Background

Previous studies have shown a connection between physical activity and migraines, but they don't prove a cause-and-effect relationship due to potential biases in observational methods.

Methods

Utilizing accelerometer-measured physical activity data from a cohort of 377,234 participants in the UK Biobank and information from 599,356 European migraine patients (including 48,975 cases and 550,381 controls) obtained from 24 cohorts, we performed a bidirectional Mendelian randomization analysis to investigate the genetic bidirectional causal relationship between accelerometer-measured physical activity and migraines.

Results

Research findings indicated a slight negative genetic correlation between "average acceleration" physical activity (rg  = -0.091, p = 0.011), overall physical activity (rg  = -0.081, p = 0.017), and migraine. Nevertheless, no shared genetic components were observed between migraine and "fraction of accelerations > 425 mg" of physical activity (rg  = -0.124, p = 0.076). The study results also demonstrated a lack of genetic bidirectional causality between accelerometer-measured physical activity and migraine ("average acceleration", OR = 1.002, 95% CI 0.975-1.031, p = 0.855, "fraction of accelerations > 425 mg", OR = 1.127, 95% CI 0.802-1.583, p = 0.488, overall physical activity, OR = 0.961, 95% CI 0.713-1.296, p = 0.799), and vice versa. Additionally, this lack of causal association persists even after adjusting for obesity (OR = 1.005, p = 0.578), education (OR = 1.019, p = 0.143), and depression (OR = 1.005, p = 0.847), either separately or simultaneously.

Conclusion

The Mendelian randomization results based on genetic data do not provide support for a causal association between physical activity and migraine.

Prospective prediction of anxiety onset in the Canadian longitudinal study on aging (CLSA): A machine learning study

BACKGROUND

Anxiety disorders are among the most common mental health disorders in the middle aged and older population. Because older individuals are more likely to have multiple comorbidities or increased frailty, the impact of anxiety disorders on their overall well-being is exacerbated. Early identification of anxiety disorders using machine learning (ML) can potentially mitigate the adverse consequences associated with these disorders.

METHODS

We applied ML to the data from the Canadian Longitudinal Study on Aging (CLSA) to predict the onset of anxiety disorders approximately three years in the future. We used Shapley value-based methods to determine the top factor for prediction. We also investigated whether anxiety onset can be predicted by baseline depression-related predictors alone.

RESULTS

Our model was able to predict anxiety onset accurately (Area under the Receiver Operating Characteristic Curve or AUC = 0.814 ± 0.016 (mean ± standard deviation), balanced accuracy = 0.741 ± 0.016, sensitivity = 0.743 ± 0.033, and specificity = 0.738 ± 0.010). The top predictive factors included prior depression or mood disorder diagnosis, high frailty, anxious personality, and low emotional stability. Depression and mood disorders are well known comorbidity of anxiety; however a prior depression or mood disorder diagnosis could not predict anxiety onset without other factors.

LIMITATION

While our findings underscore the importance of a prior depression diagnosis in predicting anxiety, they also highlight that it alone is inadequate, signifying the necessity to incorporate additional predictors for improved prediction accuracy.

CONCLUSION

Our study showcases promising prospects for using machine learning to develop personalized prediction models for anxiety onset in middle-aged and older adults using easy-to-access survey data.

Diversity, Equity, and Inclusion in Headache Care and Research

ABSTRACT

This article reviews the disparities faced by individuals who experience headache disorders and discusses potential solutions to deliver equitable care. Disparities exist in the diagnosis and treatment of headache disorders with regard to race, ethnicity, sex, gender, sexual orientation, geography, and socioeconomic status. Furthermore, research in the realm of headache disparities is inadequate, and the clinical trial representation of patients from underserved communities is poor. Many barriers exist to optimizing care for underserved communities and this article addresses these barriers and presents ways to combat them.

Limitations and Future Directions in Sex, Sexuality, and Gender Diverse Research in Neurology

Sex, sexuality, and gender diversity is understudied and underserved in neurology. Neurology research inclusive of LGBTQIA+ (lesbian, gay, bisexual, transgender, queer, intersex, asexual) people is limited. Existing research struggles with a paucity of neurology studies collecting sex, sexuality, and gender diverse (SSGD) data, conflation of sex and gender, lack of precision in measures, neglect of younger and older populations, nebulous benefit to community, and absent intersectionality. Future directions in SSGD neurology research include precise and community-based measurements, respect for LGBTQIA+ colleagues, and the application of minority stress models. All patients stand to benefit from research that elucidates how SSGD variables influence neurological health. ANN NEUROL 2024;95:421-431.

Higher Risk of Many Physical Health Conditions in Sexual Minority Men: Comprehensive Systematic Review and Meta-Analysis in Gay- and Bisexual-Identified Compared with Heterosexual-Identified Men

Purpose: The purpose of this study was to provide a systematic review and, where possible, meta-analysis on the prevalence of physical health conditions in sexual minority men (SMM, i.e., gay- and bisexual-identified men) compared with heterosexual-identified men. Methods: A systematic literature search in the databases MEDLINE, Embase, CENTRAL, CINAHL, and Web of Science was conducted on epidemiological studies on physical health conditions, classified in the Global Burden of Disease project and published between 2000 and 2021. Meta-analyses comparing odds ratios were calculated. Results: In total, 23,649 abstracts were screened, and 32 studies were included in the systematic review. Main findings were that (1) Largest differences in prevalence by sexual identity were found for chronic respiratory diseases, particularly asthma: overall, SMM were significantly almost 50% more likely to suffer from asthma than heterosexual men. (2) Evidence of higher prevalence was also found for chronic kidney diseases and headache disorders in gay men and for hepatitis B/C in both gay and bisexual men. (3) We found an overall trend that bisexual men were more affected by some of the physical health conditions compared with gay men (e.g., cardiovascular diseases, asthma). However, regarding cancer, headache disorders, and hepatitis, gay men were more affected. Conclusion: We found evidence of physical health disparities by sexual identity, suggesting more health issues in SMM. Since some of these findings rely on few comparisons or small samples of SMM only, this review is intended to be a vehement plea for routinely including sexual identity assessment in health research and clinical practice.

CGRP Antagonism and Ketogenic Diet in the Treatment of Migraine

The study of migraine is based on the complexity of the pathology, both at the pathophysiological and epidemiological levels. Although it affects more than a billion people worldwide, it is often underestimated and underreported by patients. Migraine must not be confused with a simple headache; it is a serious and disabling disease that causes considerable limitations in the daily life of afflicted people, including social, work, and emotional effects. Therefore, it causes a daily state of suffering and discomfort. It is important to point out that this pathology not only has a decisive impact on the quality of life of those who suffer from it but also on their families and, more generally, on society as a whole. The clinical picture of migraine is complex, with debilitating unilateral or bilateral head pain, and is often associated with characteristic symptoms such as nausea, vomiting, photophobia, and phonophobia. Hormonal, environmental, psychological, dietary, or other factors can trigger it. The present review focuses on the analysis of the physiopathological and pharmacological aspects of migraine, up to the correct dietary approach, with specific nutritional interventions aimed at modulating the symptoms. Based on the symptoms that the patient experiences, targeted and specific therapy is chosen to reduce the frequency and severity of migraine attacks. Specifically, the role of calcitonin gene-related peptide (CGRP) in the pathogenesis of migraine is analyzed, along with the drugs that effectively target the corresponding receptor. Particularly, CGRP receptor antagonists (gepants) are very effective drugs in the treatment of migraine, given their high diffusion in the brain. Moreover, following a ketogenic diet for only one or two months has been demonstrated to reduce migraine attacks. In this review, we highlight the diverse facets of migraine, from its physiopathological and pharmacological aspects to prevention and therapy.

Different Aspects of Aging in Migraine

Migraine is a common neurological disease displaying an unusual dependence on age. For most patients, the peak intensity of migraine headaches occurs in 20s and lasts until 40s, but then headache attacks become less intense, occur less frequently and the disease is more responsive to therapy. This relationship is valid in both females and males, although the prevalence of migraine in the former is 2-4 times greater than the latter. Recent concepts present migraine not only as a pathological event, but rather as a part of evolutionary adaptive response to protect organism against consequences of stress-induced brain energy deficit. However, these concepts do not fully explain that unusual dependence of migraine prevalence on age. Many aspects of aging, both molecular/cellular and social/cognitive, are interwound in migraine pathogenesis, but they neither explain why only some persons are affected by migraine, nor suggest any causal relationship. In this narrative/hypothesis review we present information on associations of migraine with chronological aging, brain aging, cellular senescence, stem cell exhaustion as well as social, cognitive, epigenetic, and metabolic aging. We also underline the role of oxidative stress in these associations. We hypothesize that migraine affects only individuals who have inborn, genetic/epigenetic, or acquired (traumas, shocks or complexes) migraine predispositions. These predispositions weakly depend on age and affected individuals are more prone to migraine triggers than others. Although the triggers can be related to many aspects of aging, social aging may play a particularly important role as the prevalence of its associated stress has a similar age-dependence as the prevalence of migraine. Moreover, social aging was shown to be associated with oxidative stress, important in many aspects of aging. In perspective, molecular mechanisms underlying social aging should be further explored and related to migraine with a closer association with migraine predisposition and difference in prevalence by sex.

Income dissatisfaction and migraine headache. Evidence from a nationwide population-based survey

Objective

We investigate whether and to what extent income dissatisfaction (ID) is an important determinant of migraine. Indeed, ID may play a more relevant role in migraines than realized income, and it may affect both low and high-income people.

Design

We exploit the Italian Statistical Institute (ISTAT) survey covering about 80,000 individuals for this study. On the methodological ground, an instrumental variable probit model has been implemented.

Main Outcome Measures

To measure income dissatisfaction we exploit a self-reported status ranging from 1 to 4, while the migraine variable captures whether the individual suffers from migraine.

Results

The results show that the higher the ID the greater the probability of having a migraine. This relationship is robust to the level of realized income, socioeconomic characteristics of the individual, and the existence of other illnesses.

Conclusions

The high relevance of ID among low-income as well as high-income people opens up a new perspective on the determinants of migraines and provides an explanation of the contrasting evidence in the literature about the income-migraine nexus.

Comprehensive systematic review and meta-analysis on physical health conditions in lesbian- and bisexual-identified women compared with heterosexual-identified women

BACKGROUND

Sexual minority individuals experience discrimination, leading to mental health disparities. Physical health disparities have not been examined to the same extent in systematic reviews so far.

OBJECTIVES

To provide a systematic review and, where possible, meta-analyses on the prevalence of physical health conditions in sexual minority women (i.e. lesbian- and bisexual-identified women) compared to heterosexual-identified women.

DESIGN

The study design is a systematic review with meta-analyses.

DATA SOURCES AND METHODS

A systematic literature search in MEDLINE, EMBASE, CENTRAL, CINAHL, and Web of Science databases was conducted on epidemiologic studies on physical health conditions, classified in the Global Burden of Disease project, published between 2000 and 2021. Meta-analyses pooling odds ratios were calculated.

RESULTS

In total, 23,649 abstracts were screened and 44 studies were included in the systematic review. Meta-analyses were run for arthritis, asthma, back pain, cancer, chronic kidney diseases, diabetes, headache disorders, heart attacks, hepatitis, hypertension, and stroke. Most significant differences in prevalence by sexual identity were found for chronic respiratory conditions, especially asthma. Overall, sexual minority women were significantly 1.5-2 times more likely to have asthma than heterosexual women. Furthermore, evidence of higher prevalence in sexual minority compared to heterosexual women was found for back pain, headaches/migraines, hepatitis B/C, periodontitis, urinary tract infections, and acne. In contrast, bisexual women had lower cancer rates. Overall, sexual minority women had lower odds of heart attacks, diabetes, and hypertension than heterosexual women (in terms of diabetes and hypertension possibly due to non-consideration of pregnancy-related conditions).

CONCLUSION

We found evidence for physical health disparities by sexual identity. Since some of these findings rely on few comparisons only, this review emphasizes the need for routinely including sexual identity assessment in health research and clinical practice. Providing a more detailed picture of the prevalence of physical health conditions in sexual minority women may ultimately contribute to reducing health disparities.

Socioeconomic and geographic inequalities in headache disability in Brazil: The 2019 National Health Survey

OBJECTIVE

To map the socioeconomic and geographic inequalities in headache disability in Brazil.

BACKGROUND

Headache disability and its social determinants are poorly investigated in Brazil.

METHODS

This is a secondary, cross-sectional analysis of the 2019 National Health Survey database, a representative sample of the Brazilian population. Working-aged Brazilians (aged ≥14 years) were included in the analyses (n = 225,563). Headache disability was inquired through questions on the number of days the respondent was unable to perform customary daily activities in the past 2 weeks. Proportion estimates and the mean days lost were compared between socioeconomic categories. Sample weights were used.

RESULTS

Among 14 disease-related disability groups, headache disability (n = 1228) was the second most prevalent disability in adolescents and fifth among adults aged <50 years. In the headache disability sample, there was a higher proportion of females at 72.4% (95% confidence interval [CI] 68.5%-75.9%), with a mean (95% CI) age of 41.1 (40.1-42.0) years and days lost due to disability of 3.4 (3.2-3.6) days. The sociodemographic distribution across income strata (quartiles) of the headache disability sample showed the highest proportions at the lowest income quartile in the Northeast region (15.4%, 95% CI 12.8%-18.4%), for people of Brown color (17.5%, 95% CI 14.7%-20.7%), and with the lowest education level (l3.6%, 95% CI 11.3%-16.2%). Black people, those from the North region, and those with the lowest education level had more days lost than White people (mean [95% CI] 4.1 [3.5-4.6] vs. 3.1 [2.8-3.4] days, p = 0.008), those from the Southeast region (mean [95% CI] 3.8 [3.4-4.2] vs. 2.8 [2.4-3.3] days, p = 0.022), and people with the highest education level (mean [95% CI] 3.9 [3.6-4.2] vs. 2.8 [2.3-3.3] days, p = 0.005), respectively.

CONCLUSION

In Brazil, headache disability is one of the leading causes of disability and it is characterized by socioeconomic inequalities.

Migraine, Migraine Disability, Trauma, and Discrimination in Sexual and Gender Minority Individuals

BACKGROUND AND OBJECTIVES

This study sought to describe migrainous headache frequency and severity and to examine the relationship between trauma, discrimination, and migraine-associated disability in a sample of sexual and/or gender minority (SGM) adults.

METHODS

We performed a cross-sectional study of SGM people in The Population Research in Identity and Disparities for Equality Study from August to October 2018. The primary exposure was any trauma or discrimination, regardless of attribution. The primary outcome was moderate-severe migraine disability, as defined by a Migraine Disability Assessment (MIDAS) Questionnaire score of ≥11. We performed descriptive analysis comparing respondents with any migrainous headache with those without. Multivariable logistic regression examined the association between trauma/discrimination and migraine disability, controlling first for sociodemographic and clinical factors and then for psychiatric comorbidities.

RESULTS

Of the 3,325 total respondents, 1,126 (33.9%) screened positive for migrainous headache by ID-Migraine criteria. Most people with migraine self-reported moderate (n = 768, 68.2%) or severe (n = 253, 22.5%) intensity. The median MIDAS score was 11 (interquartile range 5-25). Most respondents with migraine (n = 1,055, 93.7%) reported a history of trauma or discrimination. In unadjusted analysis, exposure to both trauma and discrimination was associated with higher odds of moderate-severe disability (OR 1.76, 95% CI 1.34-2.32). After adjustment for self-reported psychiatric comorbidities of anxiety, depression, and posttraumatic stress disorder, this association lost statistical significance.

DISCUSSION

Migrainous headache is common among our sample of SGM adults, and prior experiences with trauma and discrimination are associated with increased migraine disability. Our findings suggest that psychiatric comorbidities play a significant role in this relationship, identifying a potentially modifiable risk factor for disability in SGM people with migraine.

Epidemiology and treatment utilization for Canadian patients with migraine: a literature review

The objective of this narrative review was to identify real-world evidence regarding the burden of migraine in Canada. We conducted a literature search in MEDLINE, Embase, and the Cochrane Database of Systematic Reviews for studies published between August 2010 and August 2020. Of the 3269 publications identified, 29 studies were included. Prevalence estimates varied widely across Canada, and mental health comorbidities were common. Individuals with migraine have a lower quality of life, detrimental impact on workforce productivity, and higher rates of health care resource utilization (HCRU), with HCRU and costs highest among those with chronic migraine. We found inconsistencies in care, including underutilization of medications such as triptans, and varied utilization of over-the-counter and prescription medications. Increased medication use was identified among those with chronic migraine, and only a small number of patients used migraine preventive medications. The burden of migraine in Canada is substantial. Reduced quality of life and workforce productivity, increased HCRU and costs, and underutilization of triptans and migraine preventive medications highlight an important need for more effective management of individuals with migraine.

Social Determinants of Health and its Role in Headache Disorders

Editorial

Social Determinants of Health in Neurology

Neurologic health disparities are created and perpetuated by structural and social determinants of health. These factors include, but are not limited to, interpersonal bias, institutional factors that lead to disparate access to care, and neighborhood-level factors, such as socioeconomic status, segregation, and access to healthy food. Effects of these determinants of health can be seen throughout neurology, including in stroke, epilepsy, headache, amyotrophic lateral sclerosis, multiple sclerosis, and dementia. Interventions to improve neurologic health equity require multilayered approaches to address these interdependent factors that create and perpetuate disparate neurologic health access and outcomes.

Physical inactivity and headache disorders: Cross-sectional analysis in the Brazilian Longitudinal Study of Adult Health (ELSA-Brasil)

BACKGROUND

Physical inactivity has been linked to headache disorders but estimates based on the current World Health Organization physical activity guidelines are unknown.

OBJECTIVE

To test the associations between headache disorders and physical inactivity in the ELSA-Brasil cohort.

METHODS

In a cross-sectional analysis, linear (continuous variables) and logistic regression models (categorical variables) tested the associations of physical activity levels in the leisure time, commuting time, and combined leisure time physical activity + commuting time physical activity domains with headache disorders, adjusted for the effects of sociodemographic data, cardiovascular risk variables, psychiatric disorders, and migraine prophylaxis medication.

RESULTS

Of 15,105 participants, 14,847 (54.4% women) provided data on physical activity levels and headache. Higher physical activity levels (continuous values) in the leisure time physical activity domain associated with lower migraine and tension-type headache occurrence and lower headache attack frequency, while in the commuting time physical activity domain it associated with more frequent headache attacks. Compared to people who met World Health Organization physical activity levels in the leisure time physical activity or combining leisure time physical activity + commuting time physical activity domains (i.e. ≥150 min.wk^-1 of moderate and/or ≥75 min.wk^-1 of vigorous physical activity), physical inactivity associated with higher migraine occurrence, while somewhat active (i.e. not meeting World Health Organization recommendations) associated with higher migraine and tension-type headache occurrence. Physical inactivity in the commuting time physical activity domain associated with higher tension-type headache in men and lower migraine in women. Physical inactivity within vigorous leisure time physical activity intensity, but not moderate leisure time physical activity, associated with higher migraine, mostly in women. Finally, physical inactivity associated with higher headache attack frequency regardless headache subtype.

CONCLUSION

Physical inactivity and unmet World Health Organization physical activity levels associate with primary headaches, with heterogeneous associations regarding headache subtype, sex, physical activity domain/intensity, and headache frequency in the ELSA-Brasil study.

The prevalence and impact of migraine and severe headache in the United States: Updated age, sex, and socioeconomic-specific estimates from government health surveys

BACKGROUND AND OBJECTIVES

Accurate, up-to-date estimates of the burden of migraine and severe headache are important for evidence-based decision-making about workforce needs and the distribution of health resources. We used data from US government health surveys to report the prevalence, trends, and impact of this condition by age, sex, and poverty status.

METHODS

We identified the most recent, publicly available summary statistics from the National Hospital Ambulatory Medical Care Survey, the National Ambulatory Medical Care Survey, and the National Health Interview Survey. We extracted and compiled relevant information from each study, with an emphasis on sex, age, and economic-related statistics.

RESULTS

The age-adjusted prevalence of migraine and severe headache in the United States has remained stable over many years. In 2018, the age-adjusted prevalence was 15.9% across all adults. The sex ratio also remains stable, with 21% of women and 10.7% of men affected. Migraine continues to be an important public health problem, accounting for roughly 4 million emergency department (ED) visits in 2016, when headache was the fifth most common reason for an ED visit overall and the third most common reason for ED visits in females 15-64. Migraine also accounted for over 4.3 million office visits. Many adults with migraine or severe headaches are disadvantaged. In 2018, for example, roughly 40% of US adults with migraine were unemployed, and a similar proportion were classified as poor or "near poor." Roughly one in five had no health insurance and about a third had a high school education or less.

CONCLUSIONS

Migraine and severe headaches are a serious public health issue in the United States, with the highest impact in women of childbearing age and those of lower socioeconomic status. Socioeconomic disadvantages also are highly prevalent among those with headaches. The economic consequences of the current coronavirus pandemic are likely to exacerbate all of these inequities. Increased attention to this high impact chronic pain condition, and improved funding for treatment provision and research, are warranted to reduce the future burden of disease.

Giving Researchers a Headache - Sex and Gender Differences in Migraine

Migraine is a common neurovascular disorder affecting ~15% of the general population. Ranking second in the list of years lived with disability (YLD), people living with migraine are greatly impacted by this especially burdensome primary headache disorder. In ~30% of individuals with migraine, transient neurological symptoms occur (migraine aura) that further increase migraine burden. However, migraine burden is differential with respect to sex. Though one-year prevalences in childhood are similar, starting with puberty, migraine incidence increases at a much higher rate in females than males. Thus, migraine over the life course occurs in women three to four times more often than in men. Attacks are also more severe in women, leading to greater disability and a longer recovery period. The sex disparity in migraine is believed to be partly mediated through fluctuations in ovarian steroid hormones, especially estrogen and progesterone, although the exact mechanisms are not yet completely understood. The release of the neuropeptide calcitonin gene-related peptide (CGRP), followed by activation of the trigeminovascular system, is thought to play a key role in the migraine pathophysiology. Given the burden of migraine and its disproportionate distribution, the underlying cause(s) for the observed differences between sexes in the incidence, frequency, and intensity of migraine attacks must be better understood. Relevant biological as well as behavioral differences must be taken into account. To evaluate the scope of the existing knowledge on the issue of biological sex as well as gender differences in migraine, we conducted a systematized review of the currently available research. The review seeks to harmonize existing knowledge on the topic across the domains of biological/preclinical, clinical, and population-level research, which are traditionally synthesized and interpreted in isolation. Ultimately, we identify knowledge gaps and set priorities for further interdisciplinary and informed research on sex and gender differences as well as gender-specific therapies in migraine.