The renin-angiotensin system: a possible contributor to migraine pathogenesis and prophylaxis

Deep and unbiased proteomics, pathway enrichment analysis, and protein-protein interaction of biomarker signatures in migraine

Background

Currently, there are no biomarkers for migraine.

Objectives

We aimed to identify proteomic biomarker signatures for diagnosing, subclassifying, and predicting treatment response in migraine.

Design

This is a cross-sectional and longitudinal study of untargeted serum and cerebrospinal fluid (CSF) proteomics in episodic migraine (EM; n = 26), chronic migraine (CM; n = 26), and healthy controls (HC; n = 26).

Methods

We developed classification models for biomarker identification and natural clusters through unsupervised classification using agglomerative hierarchical clustering (AHC). Pathway analysis of differentially expressed proteins was performed.

Results

Of 405 CSF proteins, the top five proteins that discriminated between migraine patients and HC were angiotensinogen, cell adhesion molecule 3, immunoglobulin heavy variable (IGHV) V-III region JON, insulin-like growth factor binding protein 6 (IGFBP-6), and IGFBP-7. The top-performing classifier demonstrated 100% sensitivity and 75% specificity in differentiating the two groups. Of 229 serum proteins, the top five proteins in classifying patients with migraine were immunoglobulin heavy variable 3-74 (IGHV 3-74), proteoglycan 4, immunoglobulin kappa variable 3D-15, zinc finger protein (ZFP)-814, and mediator of RNA polymerase II transcription subunit 12. The best-performing classifier exhibited 94% sensitivity and 92% specificity. AHC separated EM, CM, and HC into distinct clusters with 90% success. Migraine patients exhibited increased ZFP-814 and calcium voltage-gated channel subunit alpha 1F (CACNA1F) levels, while IGHV 3-74 levels decreased in both cross-sectional and longitudinal serum analyses. ZFP-814 remained upregulated during the CM-to-EM reversion but was suppressed when CM persisted. CACNA1F was pronounced in CM persistence. Pathway analysis revealed immune, coagulation, glucose metabolism, erythrocyte oxygen and carbon dioxide exchange, and insulin-like growth factor regulation pathways.

Conclusion

Our data-driven study provides evidence for identifying novel proteomic biomarker signatures to diagnose, subclassify, and predict treatment responses for migraine. The dysregulated biomolecules affect multiple pathways, leading to cortical spreading depression, trigeminal nociceptor sensitization, oxidative stress, blood-brain barrier disruption, immune response, and coagulation cascades.

Trial registration

NCT03231241, ClincialTrials.gov.

Current understanding of the link between angiotensin-converting enzyme and pain perception

The renin-angiotensin system (RAS) is known to affect diverse physiological processes that affect the functioning of many key organs. Angiotensin-converting enzyme (ACE) modulates a variety of bioactive peptides associated with pain. ACE inhibitors (ACEis) have found applications in the treatment of cardiovascular, kidney, neurological and metabolic disorders. However, ACEis also tend to display undesirable effects, resulting in increased pain sensitization and mechanical allodynia. In this review, we provide comprehensive discussion of preclinical and clinical studies involving the evaluation of various clinically approved ACEis. With the emerging knowledge of additional factors involved in RAS signaling and the indistinct pharmacological role of ACE substrates in pain, extensive studies are still required to elucidate the mechanistic role of ACE in pain perception.

Arterial hypertension in the chronic evolution of migraine: bystander or risk factor? An overview

BACKGROUND

Several risk factors are associated with the chronic evolution of migraine. Clinical and preclinical studies have provided data about the role of hypertension (HT) as one of the potential modifiable risk factors of chronic migraine (CM). This review is focused on the biological and clinical evidence supporting common mechanisms underlying HT and migraine and the potential role of HT in the transition from episodic to chronic migraine.

METHODS

We conducted a narrative review from a literature search covering the available evidence from studies investigating: i) the role of HT in the transition to CM in clinical practice; ii) the biological mechanisms potentially underpinning the association between HT and evolution to CM; iii) the role of antihypertensive medications in migraine prophylaxis.

RESULTS

HT proved to be at the base of multiple mechanisms underlying migraine and migraine chronicization. Endothelial dysfunction, blood-brain barrier alterations, calcitonin gene-related peptide signaling, and renin-angiotensin-aldosterone system dysregulation are involved in the worsening effect of HT on migraine frequency, and the role of HT in the transition to CM is supported by clinical observations.

CONCLUSIONS

The observed evidence supports HT contribution to CM evolution due to shared pathophysiologic mechanisms. While a bidirectional influence appears to be ascertained, data are still lacking about the one-way role of HT as direct risk factor for CM transition. Further research is needed to confirm a causal role of HT in this process.

Association of Migraine and Vasomotor Symptoms

OBJECTIVE

To further examine a potential link between migraine and vasomotor symptoms as well as hypertension as a cardiovascular disease risk factor, potentially explaining the association in midlife women.

PATIENTS AND METHODS

We conducted a cross-sectional analysis from the Data Registry on Experiences of Aging, Menopause, and Sexuality using questionnaire data from women aged 45 to 60 years seen in women's clinics at a tertiary care center from May 15, 2015, through January 31, 2022. A history of migraine was self-reported; menopause symptoms were assessed with the Menopause Rating Scale. Associations between migraine and vasomotor symptoms were evaluated utilizing multivariable logistic regression models adjusting for multiple factors.

RESULTS

Of 5708 women included in the analysis, 1354 (23.7%) reported a migraine history. The total cohort had a mean age of 52.8 years, most (5184 [90.8%]) were White, and 3348 (58.7%) were postmenopausal. In adjusted analysis, women with migraine were significantly more likely to have severe/very severe hot flashes vs no hot flashes compared with women without migraine (odds ratio, 1.34; 95% CI, 1.08 to 1.66; P=.007). Migraine was associated with a diagnosis of hypertension in adjusted analysis (odds ratio, 1.31; 95% CI, 1.11 to 1.55; P=.002).

CONCLUSION

This large cross-sectional study confirms an association between migraine and vasomotor symptoms. Migraine also was associated with hypertension, potentially providing a link with cardiovascular disease risk. Given the high prevalence of migraine in women, this association may help identify those at risk for more severe menopause symptoms.

Consensus of the Brazilian Headache Society (SBCe) for prophylactic treatment of episodic migraine: part II

BACKGROUND

Migraine affects 1 billion people worldwide and > 30 million Brazilians; besides, it is an underdiagnosed and undertreated disorder.

OBJECTIVE

The need to disseminate knowledge about the prophylactic treatment of migraine is known, so the Brazilian Headache Society (SBCe, in the Portuguese acronym) appointed a committee of authors with the objective of establishing a consensus with recommendations on the prophylactic treatment of episodic migraine based on articles from the world literature as well as from personal experience.

METHODS

Meetings were held entirely online, with the participation of 12 groups that reviewed and wrote about the pharmacological categories of drugs and, at the end, met to read and finish the document. The drug classes studied in part II of this Consensus were: antihypertensives, selective serotonin reuptake inhibitors, serotonin and norepinephrine reuptake inhibitors, calcium channel blockers, other drugs, and rational polytherapy.

RESULTS

From this list of drugs, only candesartan has been established as effective in controlling episodic migraine. Flunarizine, venlafaxine, duloxetine, and pizotifen were defined as likely to be effective, while lisinopril, enalapril, escitalopram, fluvoxamine, quetiapine, atorvastatin, simvastatin, cyproheptadine, and melatonin were possibly effective in prophylaxis of the disease.

CONCLUSIONS

Despite an effort by the scientific community to find really effective drugs in the treatment of migraine, given the large number of drugs tested for this purpose, we still have few therapeutic options.

Nomogram for Postoperative Headache in Adult Patients Undergoing Elective Cardiac Surgery

Background Postoperative headache (POH) is frequent after cardiac surgery; however, few studies on risk factors for POH exist. The aims of the current study were to explore risk factors related to POH after elective cardiac surgery and to establish a predictive system. Methods and Results Adult patients undergoing elective open-heart surgery under cardiopulmonary bypass from 2016 to 2020 in 4 cardiac centers were retrospectively included. Two thirds of the patients were randomly allocated to a training set and one third to a validation set. Predictors for POH were selected by univariate and multivariate analysis. POH developed in 3154 of the 13 440 included patients (23.5%) and the overall mortality rate was 2.3%. Eight independent risk factors for POH after elective cardiac surgery were identified, including female sex, younger age, smoking history, chronic headache history, hypertension, lower left ventricular ejection fraction, longer cardiopulmonary bypass time, and more intraoperative transfusion of red blood cells. A nomogram based on the multivariate model was constructed, with reasonable calibration and discrimination, and was well validated. Decision curve analysis revealed good clinical utility. Finally, 3 risk intervals were divided to better facilitate clinical application. Conclusions A nomogram model for POH after elective cardiac surgery was developed and validated using 8 predictors, which may have potential application value in clinical risk assessment, decision-making, and individualized treatment associated with POH.

Predictors and nomogram models for postoperative headache in patients undergoing heart valve surgery

Background

Headache is a frequent complication after cardiac surgery. However, studies on the risk factors of postoperative headache (POH) are rare. The purpose of this study was to identify independent risk factors for POH in patients undergoing heart valve surgery (HVS) and to develop and validate risk prediction models.

Methods

Consecutive patients undergoing open HVS from 2016 to 2019 were enrolled in this study. Patients were randomly assigned to training and validation sets at a 2:1 ratio. Univariate and multivariate analysis were applied to identify independent predictors for POH in the training set. A nomogram predicting POH was developed based on these factors, and was validated in the independent validation set.

Results

POH developed in 1,061 of the 3,853 patients (27.5%). The overall mortality was 2.9%, and it was significantly higher in patients with POH (4.3% versus 2.4%, P<0.001). In the training set, six independent predictors were identified by multivariate analysis, including female, smoking history, hypertension, headache history, left ventricular ejection fraction, and cardiopulmonary bypass time. The model demonstrated good discrimination in both the training (c-index: 0.811) and validation sets (c-index: 0.814), and calibration was assessed by visual inspection. A second nomogram was also constructed including only preoperative predictors, with good discrimination (c-index: 0.792) and calibration. The decision and clinical impact curves of the models showed good clinical utility.

Conclusions

We developed and validated two risk prediction models for POH in patients undergoing HVS. The models may have clinical utility in individualized risk assessment and preventive interventions.

Preventive Oral Treatment of Episodic Migraine: An Overview

Background

Migraine is a common primary headache disorder and Episodic migraine is characterized by the occurrence of up to 14 headache days in a month. The preventive treatment of migraine is useful in patients with frequent migraine attacks, impaired activities of daily living, failure of acute pain management, disabling aura and limitations in the use of acute treatment. It is aimed at reducing headache frequency and intensity, improve response to acute treatment of migraine and improve the quality of life.

Aim

To analyze the evidence for the efficacy and tolerability of preventive oral drugs used in the management of episodic migraine.

Methods

A narrative review of the references were reviewed by searching the literature for the articles published in PubMed in English language using all the following MeSH keywords "preventive treatment", "preventive oral treatment", AND "episodic migraine", "migraine".

Results

Out of articles identified in the search, 38 articles were reviewed for evidence and summarized. The various oral drugs used in the prevention of episodic migraine are antihypertensives (beta-blockers, calcium channel blockers and Angiotensin-converting enzyme inhibitors/Angiotensin receptor blockers), antidepressants (tricyclic antidepressants, selective serotonin reuptake inhibitors, serotonin-norepinephrine reuptake inhibitors), antiepileptic drugs (valproic acid, topiramate, lamotrigine) and other miscellaneous agents. HURT questionnaire and HALT 30 index are useful in assessing response to treatment in the follow up of migraine patients.

Conclusion

An appropriately chosen oral drug is useful in the preventive treatment of episodic migraine. In patients, who fail to respond to the preventive treatment, it is essential to review the diagnosis of migraine, titrate the dosage and duration of preventive treatment and ensure patient compliance. In those patients who fail to respond to monotherapy, polytherapy is a useful option to be considered.

Real world effectiveness and tolerability of candesartan in the treatment of migraine: a retrospective cohort study

To date, two randomized, controlled studies support the use of candesartan for migraine prophylaxis but with limited external validity. We aim to evaluate the effectiveness and tolerability of candesartan in clinical practice and to explore predictors of patient response. Retrospective cohort study including all patients with migraine who received candesartan between April 2008-February 2019. The primary endpoint was the number of monthly headache days during weeks 8-12 of treatment compared to baseline. Additionally, we evaluated the frequency during weeks 20-24. We analysed the percentage of patients with 50% and 75% response rates and the retention rates after three and 6 months of treatment. 120/4121 patients were eligible, aged 45.9 [11.5]; 100 (83.3%) female. Eighty-four patients (70%) had chronic migraine and 53 (42.7%) had medication-overuse headache. The median number of prior prophylactics was 3 (Inter-quartile range 2-5). At baseline, patients had 20.5 ± 8.5 headache days per month, decreasing 4.3 ± 8.4 days by 3 months (weeks 12-16) and by 4.7 ± 8.7 days by 6 months (paired Student's t-test, p < 0.001). The percentage of patients with a 50% response was 32.5% at 3 months and 31.7% at 6 months, while the retention rate was 85.0% and 58.3%. The number of prior treatments (Odds ratio 0.79, 95% CI 0.64-0.97) and the presence of daily headache (Odds ratio 0.39, 95% CI 0.16-0.97) were associated with a lower probability of response. Candesartan showed beneficial effects in the preventive treatment of migraine in clinical practice, including patients with chronic migraine, medication-overuse headache and resistance to prior prophylactics.

Altered Serum Levels of Renin-Angiotensin System Markers in Migraine

OBJECTIVE

To compare the serum levels of renin-angiotensin system (RAS) components between patients with migraine and healthy controls, and to evaluate whether these levels are associated with migraine severity. We hypothesized that migraine would be associated with the activation of the inflammatory arm of the RAS, possibly leading to increased levels of angiotensin (Ang) II.

BACKGROUND

Recent studies have proposed the use of drugs that interfere with RAS, a hormonal system primarily implicated in blood pressure regulation, as a prophylactic strategy for migraine. However, no previous studies have directly assessed RAS components in migraine.

METHODS

This was a cross-sectional study involving 30 patients with episodic migraine who were in the interictal period and 20 healthy controls. This study was conducted at Hospital das Clínicas (Universidade Federal de Minas Gerais, Belo Horizonte, Brazil) outpatient clinic. Headache severity was evaluated using the Headache Impact Test, version 6 (HIT-6) and the Migraine Disability Test (MIDAS) questionnaires. Given that migraine is comorbid with mood disorders, depressive and anxious symptoms were evaluated using the Beck Anxiety and Depression Inventories (BDI and BAI), respectively. Clinical and demographic data were also collected. Serum levels of angiotensin-converting enzyme (ACE), ACE2, Ang II, and Ang (1-7) were measured by enzyme-linked immunosorbent assay.

RESULTS

Patients with migraine and controls were comparable in age, body mass index, blood pressure, and depressive and anxious symptoms. Patients with migraine showed lower levels of ACE [85.2 (66.8, 101.2) vs 65.5 (54.2, 77.5); P = .005] and lower ACE/ACE2 ratio [4.3 (3.4, 5.2) vs 3.5 (2.9, 4.1); P = .032] than controls. Conversely, patients with migraine had higher levels of Ang II [309.7 ± 147.4 vs 605.4 ± 200.4; difference: -287.1 (95% CI: -391.4--182.8), P < .001] and Ang (1-7) [214.4 ± 155.8 vs 397.9 ± 217.9; difference: -184.6 (95% CI: -296.7--72.6), P = .001] than controls. There were no correlations between RAS serum markers and migraine severity scores (HIT and MIDAS) or depressive and anxious symptoms (BDI and BAI) (P > .05).

CONCLUSIONS

Altogether, our results suggest the participation of RAS in migraine pathophysiology, but not in its severity.

Cerebral vascular reactivity and the migraine-stroke relationship: A narrative review

Migraine, and especially migraine with aura, is associated with an increased risk of stroke and vascular events; however, the reasons for this association are unclear. Several studies evaluated cerebral autoregulation and vasomotor reactivity in patients with migraine compared with non-migraineurs, with conflicting results. Our narrative review aimed at summarizing their results to find the most reliable evidence in the field. Studies which used visual stimuli to evoke vascular responses consistently showed an increased vascular reactivity in migraineurs compared with non-migraineurs, while studies which used systemic stimuli such as hyper- or hypocapnia showed inconsistent results. Therefore, central neural mechanisms might be more important than peripheral vascular mechanisms in determining the cerebral vascular responses of patients with migraine. However, a large body of evidence supports the existence of peripheral vascular dysfunction in patients with migraine. Further studies are needed to explain the complex interactions between central neural and peripheral vascular mechanisms in determining migraine and its vascular risk. Migraine preventive treatments, and especially the most recent ones with a peripheral action, might provide important insights in this field.

Other Preventive Anti-Migraine Treatments: ACE Inhibitors, ARBs, Calcium Channel Blockers, Serotonin Antagonists, and NMDA Receptor Antagonists

PURPOSE OF REVIEW

Migraine causes more years of life lived with disability than almost any other condition in the world and can significantly impact the lives of individuals with migraine, their families, and society. The use of medication for the prevention of migraine is an integral component to reducing disability caused by migraine. There are many different drug classes that have been investigated and shown efficacy in migraine prophylaxis. This article examines several of the classes of medications that are used for migraine preventive treatment, specifically, angiotensin-converting enzyme inhibitors, angiotensin receptor blockers, calcium channel blockers, serotonin antagonists, alpha-adrenergic agonists, and N-methyl-D-aspartic acid receptor antagonists.

RECENT FINDINGS

There have been randomized control trials investigating medications in these drug classes since the most recent guidelines for migraine prevention in adults were published by the American Academy of Neurology, American Headache Society, and the Canadian Headache Society. In these investigations, enalapril, candesartan, and memantine all demonstrated efficacy for migraine prevention. The evidence for these and the aforementioned drug classes are reviewed. When oral medications are being selected for migraine prevention, comorbid and coexistent medical conditions, concomitant medications, patient preference, and pregnancy and breast-feeding plans should be considered. Within the drug classes discussed, memantine and candesartan have a moderate level of evidence for efficacy.

Migraine and the risk of incident hypertension among women

Background Few studies have examined whether migraine is associated with an increased risk of incident hypertension. Methods We performed a prospective cohort study among 29,040 women without hypertension at baseline. Women were classified as having active migraine with aura, active migraine without aura, a past history of migraine, or no history of migraine. Incident hypertension was defined as new physician diagnosis or newly self-reported systolic or diastolic blood pressure ≥140 mmHg or ≥90 mmHg respectively. Cox proportional hazards models were used to evaluate the association between migraine and incident hypertension. Results During a mean follow-up of 12.2 years, 15,176 incident hypertension cases occurred. Compared to those with no history of migraine, women who experience migraine with aura had a 9% increase in their risk of developing hypertension (95% CI: 1.02, 1.18); women who experience migraine without aura had a 21% increase in their risk of developing hypertension (95% CI: 1.14, 1.28); and women with a past history of migraine had a 15% increase in their risk of developing hypertension (95% CI: 1.07, 1.23). Conclusions Women with migraine have a higher relative risk of developing hypertension compared to women without migraine.

Harnessing migraines for neural regeneration

The success of naturalistic or therapeutic neuroregeneration likely depends on an internal milieu that facilitates the survival, proliferation, migration, and differentiation of stem cells and their assimilation into neural networks. Migraine attacks are an integrated sequence of physiological processes that may protect the brain from oxidative stress by releasing growth factors, suppressing apoptosis, stimulating neurogenesis, encouraging mitochondrial biogenesis, reducing the production of oxidants, and upregulating antioxidant defenses. Thus, the migraine attack may constitute a physiologic environment conducive to stem cells. In this paper, key components of migraine are reviewed – neurogenic inflammation with release of calcitonin gene-related peptide (CGRP) and substance P, plasma protein extravasation, platelet activation, release of serotonin by platelets and likely by the dorsal raphe nucleus, activation of endothelial nitric oxide synthase (eNOS), production of brain-derived neurotrophic factor (BDNF) and, in migraine aura, cortical spreading depression – along with their potential neurorestorative aspects. The possibility is considered of using these components to facilitate successful stem cell transplantation. Potential methods for doing so are discussed, including chemical stimulation of the TRPA1 ion channel, conjoint activation of a subset of migraine components, invasive and noninvasive deep brain stimulation of the dorsal raphe nucleus, transcranial focused ultrasound, and stimulation of the Zusanli (ST36) acupuncture point.

Roads Less Traveled: Sexual Dimorphism and Mast Cell Contributions to Migraine Pathology

Migraine is a common, little understood, and debilitating disease. It is much more prominent in women than in men (~2/3 are women) but the reasons for female preponderance are not clear. Migraineurs frequently experience severe comorbidities, such as allergies, depression, irritable bowel syndrome, and others; many of the comorbidities are more common in females. Current treatments for migraine are not gender specific, and rarely are migraine and its comorbidities considered and treated by the same specialist. Thus, migraine treatments represent a huge unmet medical need, which will only be addressed with greater understanding of its underlying pathophysiology. We discuss the current knowledge about sex differences in migraine and its comorbidities, and focus on the potential role of mast cells (MCs) in both. Sex-based differences in pain recognition and drug responses, fluid balance, and the blood–brain barrier are recognized but their impact on migraine is not well studied. Furthermore, MCs are well recognized for their prominent role in allergies but much less is known about their contributions to pain pathways in general and migraine specifically. MC-neuron bidirectional communication uniquely positions these cells as potential initiators and/or perpetuators of pain. MCs can secrete nociceptor sensitizing and activating agents, such as serotonin, prostaglandins, histamine, and proteolytic enzymes that can also activate the pain-mediating transient receptor potential vanilloid channels. MCs express receptors for both estrogen and progesterone that induce degranulation upon binding. Furthermore, environmental estrogens, such as Bisphenol A, activate MCs in preclinical models but their impact on pain pathways or migraine is understudied. We hope that this discussion will encourage scientists and physicians alike to bridge the knowledge gaps linking sex, MCs, and migraine to develop better, more comprehensive treatments for migraine patients.

Migraine and risk of ischaemic heart disease: a systematic review and meta-analysis of observational studies

BACKGROUND AND PURPOSE

Several studies have assessed the risk of ischaemic heart diseases in migraineurs, drawing different conclusions. To define and update the issue, a systematic review and meta-analysis of the available observational studies was performed.

METHODS

PubMed and EMBASE were systematically searched up to April 2014 for observational studies dealing with the risk of any form of ischaemic heart disease in migraineurs. Studies assessing migraine as exposure and several types of ischaemic heart disease as outcomes were included in the analysis. A random effects model was used to pool the effect sizes.

RESULTS

Out of 3348 records, 15 studies (one case-control, one cross-sectional and 13 cohort studies) were identified and were included in the meta-analysis. The pooled analysis indicated an increased risk of myocardial infarction (pooled adjusted effect estimate 1.33, 95% confidence interval 1.08-1.64; P = 0.007) and of angina (pooled adjusted effect estimate 1.29, 95% confidence interval 1.17-1.43; P < 0.0001) in migraineurs compared to non-migraineurs.

CONCLUSIONS

Based on our data indicating an association of migraine with myocardial infarction and angina and on previous data showing an association of migraine, and particularly migraine with aura, with an increased risk for stroke, migraine can be appropriately considered an overall risk factor for cardiovascular diseases.

Conventional vascular risk factors: their role in the association between migraine and cardiovascular diseases

INTRODUCTION

Migraine, in particular migraine with aura, has been found to be associated with cardiovascular disease. However, the role of conventional vascular risk factors in the association is still debated. The aim of the present review is to address the association between migraine and conventional cardiovascular risk factors as well as to address their possible role in the association between migraine and cardiovascular disease.

METHODS

Data for this review were obtained through searches in multiple sources up to May 2014 using the terms "migraine" OR "headache" in combination with all the vascular risk factors of interest.

RESULTS

Data about the possible association between migraine and high blood pressure values are heterogeneous, hindering any final conclusion. Data addressing the possible association between migraine and diabetes mellitus indicate the lack of any association or in some cases a negative association between the two conditions. The body of evidence on the role of dyslipidemia in migraineurs is relatively homogeneous and, with few exceptions, reports an association between migraine and an unfavorable lipid profile; however, the difference in lipid levels between migraineurs and non-migraineurs is small and its clinical implication unclear. Regarding obesity, a trend has been observed of increased risk of migraine with increasing obesity, especially in young patients, albeit in the midst of conflicting data. Evidence about the association between cigarette smoking and migraine mostly indicates that migraineurs are more commonly smokers than non-migraineurs. On the other hand, the majority of the available studies report less alcohol use in migraineurs than in non-migraineurs. Finally, many of the available studies suggest a more frequent family history of cardiovascular disease in migraineurs as compared to non-migraineurs. Since most of the studies that supported the association between migraine and cardiovascular disease adjusted the analyses for the presence of several vascular risk factors, they cannot entirely explain this association.

CONCLUSIONS

Based on the available reported data, it seems unlikely that the higher risk of cardiovascular disease in migraineurs is mediated by any single vascular risk factor. For this reason the role of specific interactions among risk factors with the contribution of genetic, environmental, personality and psychological factors should be appropriately investigated.