Association of a Cyclical Migraine Phenotype With Disease Progression: A One-Year Time Series Analysis

Rates and risk factors for migraine progression using multiple definitions of progression: Results of the longitudinal OVERCOME (US) study

OBJECTIVE

To estimate rates of migraine progression and assess predictors of progression in a large, longitudinal cohort study using the traditional definition and two alternative definitions of migraine progression.

BACKGROUND

Traditionally, migraine progression is defined as moving from episodic migraine (EM) with ≤ 14 monthly headache days (MHD) to chronic migraine (CM) with ≥ 15 MHDs of which 8 are attributable to migraine. This definition does not take into account changes in the full range of potential headache days, disability, or impact on function.

METHODS

The Observational Survey of the Epidemiology, Treatment, and Care of Migraine (OVERCOME) study identified, characterized, and followed a representative sample of adults with migraine in the United States. Migraine was defined based on the International Classification of Headache Disorders, 3rd edition (ICHD-3) criteria. We estimated rates of migraine progression at 1 year of follow-up using three definitions: (1) traditional EM-to-CM transition, (2) increase of ≥ 5 MHDs (MHD progression), and (3) increase of ≥ 5 points on the Migraine Disability Assessment (MIDAS) scale (MIDAS progression). The analysis identified sociodemographic, clinical, and migraine-related characteristics associated with each definition of progression from a set of 67 candidates and then determined the association with progression for each candidate predictor and each definition of progression.

RESULTS

A total of 11,634 participants met ICHD-3 criteria for migraine at baseline and completed the 1-year follow-up survey. The average age was 48.2 years, and average years living with migraine was 22.8 years. The sample was 75.6% female (8793/11,634), 84.4% White (9814/11,634), 6.5% Black (757/11,634), and 7.6% Hispanic (889/11,634). The majority (89.2%, 10,374/11,634) had EM at baseline, and among these, 4.7% progressed to CM over 1 year of follow-up. Rates of progression at 1 year were higher using other definitions of progression, with 9.6% (1087/11,329) reporting an increase in ≥ 5 MHDs and 21.7% (2519/11,630) reporting an increase of ≥ 5 MIDAS points. Across all three definitions of progression, ever taking preventive medications for migraine placed people at lower odds of progressing (odds ratio [95% confidence interval]: EM-to-CM transition, 0.7 [0.57-0.85]; MHD progression, 0.9 [0.75-1.00]; MIDAS progression, 0.8 [0.73-0.91]), while the presence of depression placed people at higher odds of progressing (odds ratio [95% confidence interval]: EM-to-CM transition, 1.3 [1.05-1.69]; MHD progression, 1.4 [1.21-1.67]; MIDAS progression, 1.2 [1.04-1.34]).

CONCLUSION

This work expands the concept of migraine progression, exploring two alternative definitions that modify the potential range of MHD changes and take disability into account. This analysis identified never having used preventive medications for migraine and presence of depression as risk factors across all three definitions of progression. This work may more accurately identify persons with progression and at risk of migraine progression, setting the stage for trials of preventive intervention and ultimately more effective practice.

Setting higher standards for migraine prevention: A position statement of the International Headache Society

Migraine is one of the most prevalent and disabling neurological diseases, significantly affecting quality of life and productivity, as well as contributing to substantial societal costs. Recent innovations, including calcitonin gene-related peptide (CGRP) pathway inhibitors and onabotulinumtoxinA, have transformed migraine prevention by offering high efficacy and excellent tolerability, thus improving adherence. Clinical trials and real-world studies show that significant reductions in migraine frequency and, in some cases, complete migraine freedom is achievable. In this Position Statement, we advocate for raising the standards of migraine prevention by setting ambitious treatment goals aimed at optimal outcomes, such as migraine freedom or very low number of days with migraine or moderate/severe headache. We emphasize the importance of addressing residual migraine burden, highlighting that achieving a ≥50% reduction in monthly migraine days, although often considered a successful response, may not fully restore quality of life. Relying solely on percentage-based improvements can obscure the persisting impact of residual burden. This Position Statement does not want to change the standards for clinical trials but aims primarily at real-world clinical practice and proposes a shift from percentage-based measures of success to absolute goals while on treatment. We outline a framework that categorizes outcomes into four tiers: migraine freedom (no days with migraine or moderate-to-severe headache), optimal control (less than four days with migraine or moderate-to-severe headache), modest control (four to six days with migraine or moderate-to-severe headache) and insufficient control (more than days with migraine or moderate-to-severe headache). Focusing on residual burden while on treatment aims to further improve patient quality of life and drive innovation in preventive therapies and non-pharmacological approaches. By advocating for higher standards, this Position Statement, is not aimed primarily to drive reimbursement policies for migraine preventive treatments, but seeks to inspire clinicians, researchers and policymakers to prioritize ambitious goals in migraine prevention, ultimately enhancing patient outcomes and reducing the broader societal and economic impact of this debilitating condition.

Flexible modeling of headache frequency fluctuations in migraine with hidden Markov models

OBJECTIVE

To explore hidden Markov models (HMMs) as an approach for defining clinically meaningful headache-frequency-based groups in migraine.

BACKGROUND

Monthly headache frequency in patients with migraine is known to vary over time. This variation has not been completely characterized and is not well accounted for in the classification of individuals as having chronic or episodic migraine, a diagnosis with potentially significant impacts on the individual. This study investigated variation in reported headache frequency in a migraine population and proposed a model for classifying individuals by frequency while accounting for natural variation.

METHODS

The American Registry for Migraine Research (ARMR) was a longitudinal multisite study of United States adults with migraine. Study participants completed quarterly questionnaires and daily headache diaries. A series of HMMs were fit to monthly headache frequency data calculated from the diary data of ARMR.

RESULTS

Changes in monthly headache frequency tended to be small, with 47% of transitions resulting in a change of 0 or 1 day. A substantial portion (24%) of months reflected daily headache with individuals ever reporting daily headache likely to consistently report daily headache. An HMM with four states with mean monthly headache frequency emissions of 3.52 (95% Prediction Interval [PI] 0-8), 10.10 (95% PI 4-17), 20.29 (95% PI 12-28), and constant 28 days/month had the best fit of the models tested. Of sequential month-to-month headache frequency transitions, 12% were across the 15-headache days chronic migraine cutoff. Under the HMM, 38.7% of those transitions involved a change in the HMM state, and the remaining 61.3% of the time, a change in chronic migraine classification was not accompanied by a change in the HMM state.

CONCLUSION

A divide between the second and third states of this model aligns most strongly with the current episodic/chronic distinction, although there is a meaningful overlap between the states that supports the need for flexibility. An HMM has appealing properties for classifying individuals according to their headache frequency while accounting for natural variation in frequency. This empirically derived model may provide an informative classification approach that is more stable than the use of a single cutoff value.

Time and headache: Insights into timing processes in primary headache disorders for diagnosis, underlying pathophysiology and treatment implications

BACKGROUND

Time in headache disorders is crucial for diagnosis and gives insight into headache pathophysiology.

OBJECTIVE

To summarize published studies which describe timing processes in both attack presentation (onset, duration) and disease characterization (age of onset, evolution over time) in primary headache disorders and link to pathophysiology.

METHODS

A comprehensive search was conducted through Ovid MEDLINE(R) and PubMed, focusing on English-language articles from 1946 to 2023 to write the review. The International Classification of Headache Disorders, 3rd edition provided the framework for the review of primary headache disorders (migraine, tension-type headache and cluster headache).

RESULTS

Attack presentation: Migraine attacks exhibit significant circadian and infradian rhythms, influenced by hormonal levels, light sensitivity, and hypothalamic activation. Tension-type headache lacks clear chronobiological patterns, with limited understanding of its underlying mechanisms. Cluster headache displays a distinct circannual pattern, with attacks often occurring at night and relevant involvement of the hypothalamus. Disease characterization: Age of onset exhibits the earliest peak in migraine; frequency and typical features of primary headache disorders decrease over time.

CONCLUSION

This comprehensive analysis of time patterns in primary headache disorders underscores their role in phenotyping, understanding and treating primary headache disorders, offering promising avenues for advancing and tailoring headache management.

High-frequency episodic migraine: Time for its recognition as a migraine subtype?

BACKGROUND

High-frequency episodic migraine (HFEM) has gained attention in the field of headache research and clinical practice. In this narrative review, we analyzed the available literature to assess the evidence that could help decide whether HFEM may represent a distinct clinical and/or biological entity within the migraine spectrum.

METHODS

The output of the literature search included 61 papers that were allocated to one of the following topics: (i) socio-demographic features and burden; (ii) clinical and therapeutic aspects; (iii) pathophysiology; and (iv) classification.

RESULTS

Multiple features differentiate subjects with HFEM from low-frequency episodic migraine and from chronic migraine: education, employment rates, quality of life, disability and psychiatric comorbidities load. Some evidence also suggests that HFEM bears a specific profile of activation of cortical and spinal pain-related pathways, possibly related to maladaptive plasticity.

CONCLUSIONS

Subjects with HFEM bear a distinctive clinical and socio-demographic profile within the episodic migraine group, with a higher disease burden and an increased risk of transitioning to chronic migraine. Recognizing HFEM as a distinct entity is an opportunity for the better understanding of migraine and the spectrum of frequency with which it can manifest, as well as for stimulating further research and more adequate public health approaches.

Clinical factors associated with day-to-day peak pain severity in individuals with chronic migraine: A cohort study using daily prospective diary data

OBJECTIVE

To describe the association between day-to-day peak pain severity and clinical factors in individuals with chronic migraine (CM).

BACKGROUND

Little is known about how clinical factors relate to day-to-day pain severity in individuals with CM.

METHODS

Adults with CM were enrolled into this observational prospective cohort study that collected daily data about headache, associated symptoms, and lifestyle factors using a digital health platform (N1-Headache™) for 90 days. "Migraine days" were defined as days in which a headache occurred that had features described by the International Classification of Headache Disorders criteria. On these days, peak pain severity was recorded on a 4-point scale; on non-headache days peak pain severity was imputed as "0/none". The associations between peak pain severity and 12 clinical factors were modeled and adjusted for sex, age, daily headache, presence of menstrual bleeding, day of the week, and disability. All numerical and Likert scale variables were standardized prior to analysis.

RESULTS

Data were available for 392 participants (35,280 tracked days). The sample was predominantly female (90.6%), with a mean (standard deviation) age of 39.9 (12.8) years. In the final multivariable model with random intercept and slopes, higher than typical self-reported levels of standardized stress (odds ratio [OR] 1.07, 95% confidence interval [CI] 1.04-1.11), standardized irritability (OR 1.05, 95% CI 1.02-1.08), standardized sadness (OR 1.05, 95% CI 1.02-1.07), fatigue (OR 1.25, 95% CI 1.15-1.36), eyestrain (OR 1.38, 95% CI 1.26-1.52), neck pain (OR 1.94, 95% CI 1.76-2.13), skin sensitivity (OR 1.61, 95% CI 1.44-1.80), and dehydration (OR 1.29, 95% CI 1.18-1.42) were associated with higher reported peak pain severity levels, while standardized sleep quality (OR 0.96, 95% CI 0.93-0.99) and standardized waking feeling refreshed (OR 0.84, 95% CI 0.81-0.88) were associated with lower reported peak pain severity levels. The inclusion of a random intercept and random slopes improved upon more parsimonious models and illustrated large differences in individuals' reporting of peak severity according to the levels of the associated clinical factors.

CONCLUSION

Our data showed that the experience of CM, from a pain severity perspective, is complex, related to multiple clinical variables, and highly individualized. These results suggest that future work should aim to study a personalized approach to both medical and behavioral interventions for CM based on which clinical factors relate to the individual's experience of pain severity.

Insights from 25 years of onabotulinumtoxinA in migraine - mechanisms and management

OnabotulinumtoxinA (BTX-A) was first linked to beneficial effects in migraine 25 years ago and was approved by the FDA for preventive treatment of chronic migraine in 2010. The treatment has since had a major impact on the well-being of people with chronic migraine. The clinical development programme for BTX-A and research since its approval have provided insights into the neuromodulatory sensory effect of BTX-A, how it can control chronic migraine despite its peripheral action, and the underlying biology of migraine as a disease. In this Review, we consider the impact that BTX-A has had on the management of chronic migraine and on the research field. We discuss the insights provided by clinical research, encompassing the clinical trials and subsequent real-world evidence, and the mechanistic insights provided by preclinical and translational research. We also provide an overview of future directions of research in the field BTX-A in migraine and the clinical translation of this research.

Migraine as an allostatic reset triggered by unresolved interoceptive prediction errors

Until now, a satisfying account of the cause and purpose of migraine has remained elusive. We explain migraine within the frameworks of allostasis (the situationally-flexible, forward-looking equivalent of homeostasis) and active inference (interacting with the environment via internally-generated predictions). Due to its multimodality, and long timescales between cause and effect, allostasis is inherently prone to catastrophic error, which might be impossible to correct once fully manifest, an early indicator which is elevated prediction error (discrepancy between prediction and sensory input) associated with internal sensations (interoception). Errors can usually be resolved in a targeted manner by action (correcting the physiological state) or perception (updating predictions in light of sensory input); persistent errors are amplified broadly and multimodally, to prioritise their resolution (the migraine premonitory phase); finally, if still unresolved, progressive amplification renders further changes to internal or external sensory inputs intolerably intense, enforcing physiological stability, and facilitating accurate allostatic prediction updating. As such, migraine is an effective 'failsafe' for allostasis, however it has potential to become excessively triggered, therefore maladaptive.

Migraine worsening after COVID-19 and COVID-19 vaccination: Are we facing a nocebo effect?

BACKGROUND AND PURPOSE

In clinical practice patients may report migraine worsening as a consequence of COVID-19 (either infection or vaccines), however, data in this area are lacking. We aimed to investigate the link between COVID-19 and COVID-19 vaccination with migraine worsening and its associated factors.

METHODS

An online survey was sent to migraine patients followed up in a Spanish Headache Clinic, collecting demographic data, and information regarding SARS-CoV-2 infection and vaccination. We asked patients if they had noticed worsening of their migraine after these events and assessed concerns about infection, vaccination and migraine worsening. We also extracted data from participants' own electronic diaries (e-diaries), including 1-month data before and after their reported infection and/or vaccination. We compared participants who self-reported migraine worsening since infection or vaccination with those who did not.

RESULTS

Of 550 participants, 44.9% (247/550) reported having had COVID-19 at least once and 83.3% (458/550) had been vaccinated. Sixty-one patients reported migraine worsening since COVID-19 and 52 since the vaccination. Among the risk factors for perceived migraine worsening in the two settings (infection and vaccination) was concern about migraine worsening itself (infection: odds ratio [OR] 2.498 [95% CI: 1.02-6.273], p = 0.046; vaccination: OR 17.3 [95% CI: confidence interval 5.3-68], p < 0.001). e-diary information was available for 136 of the 550 patients, 38.2% (52/136) for COVID-19 and 39.7% (54/136) for vaccination. We observed no significant difference in headache frequency 1 month before and after infection or vaccination, even when comparing patients with and without self-reported migraine worsening.

CONCLUSIONS

Our preliminary data point to a negligible role of the infection and vaccination on migraine worsening and to the possible presence of a nocebo effect in these settings, as a remarkable proportion of patients had a clear perception of migraine worsening.

The impact of epigenetic mechanisms in migraine: Current knowledge and future directions

BACKGROUND

Epigenetic mechanisms, including DNA methylation, microRNAs and histone modifications, may modulate the genetic expression in migraine and its interaction with internal and external factors, such as lifestyle and environmental changes.

OBJECTIVE

To summarize, contextualize and critically analyze the published literature on the current state of epigenetic mechanisms in migraine in a narrative review.

FINDINGS

The studies published to date have used different approaches and methodologies to determine the role of epigenetic mechanisms in migraine. Epigenetic changes seem to be involved in migraine and are increasing our knowledge of the disease.

CONCLUSIONS

Changes in DNA methylation, microRNA expression and histone modifications could be utilized as biomarkers that would be highly valuable for patient stratification, molecular diagnosis, and precision medicine in migraine.