Epidemiology and economic impact of migraine

Migraine in childhood: Gender differences

Migraine is a common neurological disorder in developmental age, involving up to 20% of children and adolescents. Although gender differences in migraine epidemiology and clinical characteristics have been largely investigated in adulthood, this issue is considerably less known in pediatric patients. We aim at providing an overview of gender differences in pediatric migraine. The most recent literature was reviewed taking into account the epidemiological, pathophysiological, and clinical differences between boys and girls with migraine. Although many aspects need to undergo further investigation, we conclude that different aspects of childhood migraine syndrome may vary depending on the gender and age, especially with regard to pubertal development.

Migraine-attributed burden, impact and disability, and migraine-impacted quality of life: Expert consensus on definitions from a Delphi process

Background

Migraine-attributed burden, impact, disability and migraine-impacted quality of life are important concepts in clinical management, clinical and epidemiological research, and health policy, requiring clear and agreed definitions. We aimed to formulate concise and precise definitions of these concepts by expert consensus.

Methods

We searched the terms migraine-attributed burden, impact, disability and migraine-impacted quality of life in Embase and Medline from 1974 and 1946 respectively. We followed a Delphi process to reach consensus on definitions.

Results

We found widespread conflation of concepts and inconsistent terminology within publications. Following three Delphi rounds, we defined migraine-attributed burden as “the summation of all negative consequences of the disease or its diagnosis”; migraine-attributed impact as “the effect of the disease, or its diagnosis, on a specified aspect of life, health or wellbeing”; migraine-attributed disability as “physical, cognitive and mental incapacities imposed by the disease”; and migraine-impacted quality of life as “the subjective assessment by a person with the disease of their general wellbeing, position and prospects in life”. We complemented each definition with a detailed description.

Conclusion

These definitions and descriptions should foster consistency and encourage more appropriate use of currently available quantifying instruments and aid the future development of others.

Air pollution, methane super-emitters, and oil and gas wells in Northern California: the relationship with migraine headache prevalence and exacerbation

BACKGROUND

Migraine-an episodic disorder characterized by severe headache that can lead to disability-affects over 1 billion people worldwide. Prior studies have found that short-term exposure to fine particulate matter (PM_2.5), nitrogen dioxide (NO₂), and ozone increases risk of migraine-related emergency department (ED) visits. Our objective was to characterize the association between long-term exposure to sources of harmful emissions and common air pollutants with both migraine headache and, among patients with migraine, headache severity.

METHODS

From the Sutter Health electronic health record database, we identified 89,575 prevalent migraine cases between 2014 and 2018 using a migraine probability algorithm (MPA) score and 270,564 frequency-matched controls. Sutter Health delivers care to 3.5 million patients annually in Northern California. Exposures included 2015 annual average block group-level PM_2.5 and NO₂ concentrations, inverse-distance weighted (IDW) methane emissions from 60 super-emitters located within 10 km of participant residence between 2016 and 2018, and IDW active oil and gas wells in 2015 within 10 km of each participant. We used logistic and negative binomial mixed models to evaluate the association between environmental exposures and (1) migraine case status; and (2) migraine severity (i.e., MPA score > 100, triptan prescriptions, neurology visits, urgent care migraine visits, and ED migraine visits per person-year). Models controlled for age, sex, race/ethnicity, Medicaid use, primary care visits, and block group-level population density and poverty.

RESULTS

In adjusted analyses, for each 5 ppb increase in NO₂, we observed 2% increased odds of migraine case status (95% CI: 1.00, 1.05) and for each 100,000 kg/hour increase in IDW methane emissions, the odds of case status also increased (OR = 1.04, 95% CI: 1.00, 1.08). We found no association between PM_2.5 or oil and gas wells and migraine case status. PM_2.5 was linearly associated with neurology visits, migraine-specific urgent care visits, and MPA score > 100, but not triptans or ED visits. NO₂ was associated with migraine-specific urgent care and ED visits, but not other severity measures. We observed limited or null associations between continuous measures of methane emissions and proximity to oil and gas wells and migraine severity.

CONCLUSIONS

Our findings illustrate the potential role of long-term exposure to multiple ambient air pollutants for prevalent migraine and migraine severity.

Longitudinal Impact of Parent Factors in Adolescents With Migraine and Tension-Type Headache

OBJECTIVE

To examine longitudinal associations between parent factors (parent headache frequency and disability, protective parenting behaviors, parent catastrophizing) with adolescent headache-related disability and headache frequency over 6 months.

BACKGROUND

Theoretical models propose bidirectional, longitudinal relationships between parent factors and adolescent headache. Few studies have examined this using prospective study designs.

DESIGN AND METHODS

Participants were a cohort of 239 youth ages 11-17 years with recurrent migraine (with and without aura; chronic migraine) or tension-type headache (episodic and chronic) and their parents recruited from a pediatric neurology clinic and the community who completed assessments at baseline and 6-month follow-up.

RESULTS

After controlling for demographic and clinical covariates, we found that every point increase in baseline protective parenting behavior corresponded with a 2.19-point increase in adolescent headache frequency at follow-up (P = .026, 95% CI [0.27, 4.10]). Similarly, every point increase in baseline parent catastrophizing corresponded with a 0.93-point increase in adolescent headache-related disability (P = .029, 95% CI [0.09, 1.77]) and a .13-point increase in adolescent headache frequency (P = .042, 95% CI [0.01, 0.25]) at follow-up. We also found support for the reverse association, where every point increase in baseline adolescent headache-related disability predicted a 0.03-point increase in parent catastrophizing (P = .016, 95% CI [0.01, 0.05]) and a 0.02-point increase in protective parenting behavior (P = .009, 95% CI [0.01, 0.03]) at follow-up. The remaining bidirectional, longitudinal associations tested between parent factors and adolescent headache were not statistically significant.

CONCLUSION

Findings suggest that family-based psychological interventions targeting modifiable adolescent and parent factors may lead to improvements in adolescent headache-related disability and reductions in adolescent headache frequency.

Urine dicarboxylic acids change in pre-symptomatic Alzheimer's disease and reflect loss of energy capacity and hippocampal volume

Non-invasive biomarkers will enable widespread screening and early diagnosis of Alzheimer’s disease (AD). We hypothesized that the considerable loss of brain tissue in AD will result in detection of brain lipid components in urine, and that these will change in concert with CSF and brain biomarkers of AD. We examined urine dicarboxylic acids (DCA) of carbon length 3–10 to reflect products of oxidative damage and energy generation or balance that may account for changes in brain function in AD. Mean C4-C5 DCAs were lower and mean C7-C10 DCAs were higher in the urine from AD compared to cognitively healthy (CH) individuals. Moreover, mean C4-C5 DCAs were lower and mean C7-C9 were higher in urine from CH individuals with abnormal compared to normal CSF amyloid and Tau levels; i.e., the apparent urine changes in AD also appeared to be present in CH individuals that have CSF risk factors of early AD pathology. In examining the relationship between urine DCAs and AD biomarkers, we found short chain DCAs positively correlated with CSF Aβ₄₂, while C7-C10 DCAs negatively correlated with CSF Aβ₄₂ and positively correlated with CSF Tau levels. Furthermore, we found a negative correlation of C7-C10 DCAs with hippocampal volume (p < 0.01), which was not found in the occipital volume. Urine measures of DCAs have an 82% ability to predict cognitively healthy participants with normal CSF amyloid/Tau. These data suggest that urine measures of increased lipoxidation and dysfunctional energy balance reflect early AD pathology from brain and CSF biomarkers. Measures of urine DCAs may contribute to personalized healthcare by indicating AD pathology and may be utilized to explore population wellness or monitor the efficacy of therapies in clinical trials.

Young People's Response to Parental Neurological Disorder: A Structured Review

Introduction

A significant paucity of literature exists relating to the impact on children of parental neurological disorder, with the exception of multiple sclerosis. The wider literature in this field (parental cancer, depression, alcoholism, HIV/AIDS) exhibits the many potential challenges young people might experience during serious parental illness. Given this, a literature review of parental neurological disorder is long overdue.

Methods

This review is structured around the World Health Organisation (WHO) classification of neurological disorders. The WHO identifies 10 common neurological disorders; dementia, epilepsy, headache, multiple sclerosis, neuroinfections, neurological disorders associated with malnutrition, pain associated with neurological disorders, Parkinson's disease, stroke, and traumatic brain injury. A comprehensive search of the MEDLINE database was performed using key terms for each of the 10 conditions. Results for each condition were divided in to "negative", "positive and/or neutral" and "other" child responses.

Results

The search yielded a total of 6247 titles, of which 184 underwent a full-text assessment. Sixty-five met all eligibility criteria and were thus included in the review. A number of negative issues emerged across parental conditions including the prevalence of child mood disorders, parent-child role reversal, children's need for information on the parental condition, the importance of family cohesion, the negative effect of parental psychopathology and differences between male and female children. A limited number of positive outcomes were evident in a minority of parental conditions. Outcomes measured and methodologies employed were highly heterogeneous.

Conclusion

Children generally respond negatively to parental neurological disorder. Responses varied between neurological disorders, suggesting the need for parental disease-specific guidance and clinical management where required.

Trajectory of migraine-related disability following long-term treatment with lasmiditan: results of the GLADIATOR study

BACKGROUND

Migraine is recognized as the second leading cause of disability globally. Lasmiditan is a novel, selective serotonin 5-HT1F receptor agonist developed for acute treatment of migraine. Here we analyzed effects of lasmiditan on migraine disability assessed with the Migraine Disability Assessment (MIDAS) scale for interim data from a long-term safety study.

METHODS

Completers of two single-attack parent studies were offered participation in the 1 year GLADIATOR study, that randomized participants to treatment with lasmiditan 100 mg or 200 mg taken as needed for migraine attacks of at least moderate severity. Changes in MIDAS were modeled using a mixed model repeated measures analysis.

RESULTS

The sample included 1978 patients who received ≥1 lasmiditan dose and were followed for a median of 288 days. Baseline mean MIDAS scores for the lasmiditan 100-mg and 200-mg groups were 29.4 and 28.9, respectively, indicating severe migraine-related disability. Relative to baseline, MIDAS total scores were significantly lower at 3, 6, 9, and 12 months for both dose groups. At 12 months, changes in MIDAS scores were - 12.5 and - 12.2 for lasmiditan 100 mg and 200 mg, respectively, with 49% and 53% of patients, respectively, achieving at least a 50% decrease in MIDAS total score. Statistically significant improvements were also seen for work and/or school absenteeism and presenteeism, monthly headache days, and mean headache pain intensity at all time points up to 1 year. Findings for patients who completed all visits versus those dropping out early were similar. Responses were generally similar for the lasmiditan 100 mg or 200 mg doses, between subgroups defined based on the number of baseline monthly migraine attacks (≤5 vs. >5), and also between subgroups defined by pain-free response (yes/no) during initial attacks.

CONCLUSIONS

Long-term treatment with lasmiditan was associated with significant reductions in migraine-related disability, including both work or school absenteeism and presenteeism. The similarity of responses in completers and those who dropped out suggests that selective attrition does not account for the improvements. Benefits were significant at 3 months and maintained through 12 months.

TRIAL REGISTRATION

clinicaltrials.govNCT02565186; first posted October 1, 2015.

A narrative review on the burden of migraine: when the burden is the impact on people's life

Background

The burden of headache disorders, and of migraine in particular, is multifaceted and fragmented. The aim of this narrative review is to provide a description the main topics underlying the concepts of burden and impact of migraine disorders.

Main results

MedLine has been searched for publications covering the period 1990–2018 dealing with the terms burden or impact of migraine, including both episodic and chronic migraine. The main results and themes are reported in a descriptive way, and were grouped by similarity of content into overarching categories. A total of 49 papers, published over 25 years (1994–2018), were retained for the qualitative analysis. Six main themes were identified: prevalence of migraine disorders, overall impact of migraine disorders, impact on work or school activities, family impact, interictal burden, and disease costs. Majority of included studies concluded that patients with migraine reported an higher burden or impact in one or more of the six main themes herein identified, compared to non-headache patients or to patients with tension-type headache, with a tendency towards worse outcomes consistently with higher headache frequency.

Conclusions

The results of this narrative review show that the meaning of a sentence like “migraine is a burdensome condition” is not univocal: rather, it may refer to different concepts and meanings. In our opinion, future research should focus on understanding and facing the impact of migraine on work-related activities and on everyday life activities, as these aspects are highly connected to some tangible (i.e. cost) and less tangible (i.e. interictal burden and reduced quality of life) facets of migraine burden. Disease-specific measures have been implemented and should be exploited to enhance our understanding of migraine burden. This approach would allow to better understand the real impact on people’s life of such a burdensome disease.

Recent Advances in Pharmacotherapy for Migraine Prevention: From Pathophysiology to New Drugs

Migraine is a common and disabling neurological disorder, with a significant socioeconomic burden. Its pathophysiology involves abnormalities in complex neuronal networks, interacting at different levels of the central and peripheral nervous system, resulting in the constellation of symptoms characteristic of a migraine attack. Management of migraine is individualised and often necessitates the commencement of preventive medication. Recent advancements in the understanding of the neurobiology of migraine have begun to account for some parts of the symptomatology, which has led to the development of novel target-based therapies that may revolutionise how migraine is treated in the future. This review will explore recent advances in the understanding of migraine pathophysiology, and pharmacotherapeutic developments for migraine prevention, with particular emphasis on novel treatments targeted at the calcitonin gene-related peptide (CGRP) pathway.

Cycling Through Migraine Preventive Treatments: Implications for All-Cause Total Direct Costs and Disease-Specific Costs

BACKGROUND

Migraine is a common and disabling neurological disease associated with substantial economic burden. Among patients with migraine, it is unknown if cost differences exist when preventive migraine medication (PMM) switches occur.

OBJECTIVE

To understand the cost burden and health care resource utilization of patients who discontinue or cycle through 1 (PMM1), 2 (PMM2), or ≥ 3 (PMM3) unique PMM drug classes over a 12-month period versus patients who adhere persistently to their initial PMM class.

METHODS

This retrospective observational study used the Truven Health Analytics MarketScan databases to identify adult patients with migraine initiating their first PMM class (antidepressants, antiepileptics, beta blockers, or neurotoxins) from 2011-2013 (index date = first PMM claim). Patients were required to have ≥ 2 outpatient (1 if inpatient) migraine diagnosis codes (ICD-9-CM 346.xx) from 1 year pre-index to 1 year post-index with ≥ 1 code occurring pre-index. Inclusion criteria also required 12 months of pre- and post-index continuous medical and prescription enrollment. All-cause and migraine-specific total direct costs (outpatient, inpatient, emergency department, and prescriptions), based on the 2014 Consumer Price Index, were estimated for each PMM versus a persistent subgroup during the 12-month post-index period. Propensity score bin bootstrapping, controlling for patient baseline characteristics, was used to adjust separate cost comparisons between each PMM subgroup and the persistent subgroup; bootstrap simulations yielded propensity score-adjusted P values.

RESULTS

The study population included 55,402 patients who received a PMM. The study population was mainly female (85%) with a mean age of 39.2 years and mean Charlson Comorbidity Index of 0.31. Antiepileptics were the most common drug class chosen at index across all subgroups; however, lower use of antiepileptics was observed in PMM2 and PMM3 subgroups, which were more likely to be prescribed either antidepressants or beta blockers at index. Mean all-cause total direct costs, including prescription costs, were significantly higher in PMM2 ($13,429) and PMM3 ($18,394) subgroups versus the persistent subgroup ($11,941; each adjusted pairwise comparison, P < 0.001). Mean migraine-specific total direct costs were significantly lower for the persistent subgroup ($2,420) versus PMM2 and PMM3 subgroups and escalated with increasing numbers of drug class discontinuations or switches, from a mean of $2,997 to $5,004 (both adjusted pairwise comparisons, P < 0.001). Subgroup differences in all-cause and migraine-specific direct costs were primarily due to variations in outpatient and emergency department services.

CONCLUSIONS

All-cause total direct costs rose with increasing number of PMM switches over the 12-month post-index period, and were significantly higher than in the persistent subgroup, with the exception of PMM1. Additional analyses indicated that the lack of increase between PMM-persistent and PMM1 costs was due to higher pharmacy costs that were likely related to continuous use of medication in the PMM-persistent subgroup. These data suggest an increased cost burden among patients with migraine who cycle through ≥ 2 PMMs versus those who continue to receive their initial medication class.

DISCLOSURES

Eli Lilly and Company was the sole sponsor and funder for this study and was responsible for the study design, data collection, data analysis, interpretation of data, and decision to publish the findings. All authors are employees and minor stockholders of Eli Lilly and Company. Nyhuis was employed by Eli Lilly and Company at the time of this study. The findings of this study were presented in part at the 18th Congress of the International Headache Society; September 7-10, 2017; Vancouver, Canada.

Acupuncture Decreases Matrix Metalloproteinase-2 Activity in Patients with Migraine

Objective

To evaluate the effect of acupuncture on the serum matrix metalloproteinase-2 (MMP-2) level and activity in patients with migraine.

Methods

After baseline testing, eligible patients with migraine according to the criteria of the International Headache Society who volunteered to join the study were included (n=27). The patients received 10 sessions of acupuncture treatment. The points selected were bilateral ST8, ST44, LI4, LI11, LIV3, SP6, GB1, GB14, GB20, GV14, GV20, Yintang, Taiyang and ear Shenmen. Pain was measured using a visual analogue scale (VAS). Short form-36 (SF-36) was used to determine their quality of life. Blood samples were taken before treatment and after the first and last sessions of acupuncture for measurement of MMP-2 concentration and activity.

Results

The mean VAS was 85.5±16.6 before acupuncture and was significantly decreased to 39.8±20.6 after 10 sessions of acupuncture (p<0.0001). There was a significant increase in all SF-36 scores after acupuncture compared with values before treatment (p<0.0001). No significant differences were found in MMP-2 concentrations before treatment and after the first and last sessions (p>0.05). However, there were significant changes in MMP-2 activity (p<0.0001).

Conclusions

The results of this study showed a clinically relevant decrease in MMP-2 activity in patients with migraine treated with acupuncture. The mechanism underlying the effect of acupuncture in alleviating pain may be associated with a decrease in MMP-2 activity.

Illness perception in patients with migraine: An exploratory study in a tertiary care headache centre

BACKGROUND

Illness perception is significantly related to several outcome measures in different medical conditions. However, little is known about headache-related causal attributions and cognitive and emotional representations in patients with migraine.

OBJECTIVE

To examine perceived causes of headache and demographic, clinical, and psychological correlates and predictors of illness perception in patients with migraine attending a tertiary care headache centre.

METHODS

A sample of 143 patients with migraine (85.3% women, mean age 44.0 ± 12.1 years) completed the Brief Illness Perception Questionnaire (Brief IPQ), the Symptom Questionnaire (SQ), and the Migraine Disability Assessment (MIDAS) Questionnaire. A set of demographic and clinical characteristics was also collected.

RESULTS

Stress, heredity, and nervousness were the most frequent perceived causes of headache. Female gender was significantly related to higher Brief IPQ "consequences" and "emotional response" scores. Increased psychological distress and a poorer clinical course were significantly associated with more negative illness representations. In multiple regression analysis, a longer illness duration, increased depressive symptoms, and higher levels of headache-related disability and painfulness of headache attacks independently predicted a worse illness perception.

CONCLUSIONS

In patients with migraine, depressive symptoms and a worse disease status, characterized by a longer history of suffering, higher disability and more painful headache attacks, may negatively affect illness perception. It could also be that dysfunctional illness representations lead to depressive symptoms and decrease patients' motivation to adhere to treatments, resulting in a worse outcome. Future studies should examine whether the improvement of illness perception through specific psychological interventions may promote a better adaptation to migraine.

Factors Associated with Direct Health Care Costs Among Patients with Migraine

BACKGROUND

Migraine imposes substantial economic burden on patients and the health care system. Approximately 18% of women and 6% of men suffer from migraine in the United States. This is a heterogeneous group, and little data are available to evaluate factors associated with migraine costs.

OBJECTIVE

To evaluate characteristics associated with high costs among commercially insured patients with migraine.

METHODS

This retrospective analysis identified patients with migraine in the Truven Health MarketScan Research Databases between January 2008 and June 2013. Patients were required to have 12 months continuous enrollment before and after migraine diagnoses and/or migraine-specific medications (index date). Patients with costs greater than the top 25th percentile of all-cause costs during the 12-month post-index period were classified into the upper quartile (UQ) cohort. Multiple logistic regression was used to evaluate demographic and clinical factors associated with being in the UQ cohort, and generalized linear models were used to estimate the incremental costs by select factors after controlling for other covariates.

RESULTS

In the total population, 857,073 patients (mean [SD] age: 43.2 [12.5] years), were included, with 83.2% females. Average post-index annual all-cause costs were $13,045 (SD = $25,328) with the top 25th percentile of costs at $14,120. Overall, 44.4% and 54.8% of patients had ≥ 1 pre-index claim for opioids and triptans, respectively. Patients with ≥ 2 migraine-related emergency room visits were twice as likely to be in the UQ cohort (OR = 2.13, 95% CI = 2.02-2.25; P < 0.05) and incurred $3,125 incremental all-cause costs compared with those with < 2 visits. Patients who visited a neurologist were 33.0% more likely to be in the UQ cohort and had significantly higher adjusted all-cause costs ($11,794 vs. $9,868, P < 0.05). Opioid users had a 1.5-3 times increased likelihood of being in the UQ cohort (P < 0.05); adjusted all-cause annual costs ranged from $8,888 (95% CI = $8,862-$8,914) for nonusers to $15,210 (95% CI = $15,113-$15,307) for high users (7+ claims). Patients having 7+ triptan claims were 1.2 times as likely to be in the UQ cohort compared with nonusers, with estimated costs of $11,517 (95% CI = $11,438-$11,596) for high users and $10,753 (95% CI = $10,717-$10,790) for nonusers.

CONCLUSIONS

Results suggest that certain modifiable factors, such as increased acute medication use (opioids and triptans) and more migraine-related emergency room visits are associated with higher all-cause health care costs for patients with migraine. These findings could be used to identify patients who require early intervention, enhanced symptoms monitoring, and appropriate disease management. Future studies could examine the effect of disease severity on health resource utilization and costs using survey or medical record data.

DISCLOSURES

This study was funded by Amgen and conducted by Truven Health Analytics. Bonafede, Cappell, and Kim are employees of Truven Health Analytics, which received compensation from Amgen for the overall conduct of the study and preparation of the manuscript. Cai was an employee of Truven Health Analytics at the time of this study. Sapra, Shah, and Desai are employees of Amgen. Katherine Widnell was an employee of Amgen when the manuscript draft was developed. Winner reports receiving research support from Allergan, Amgen, A-Z, Teva, Pfizer, Novartis, and Lilly. Study concept and design were contributed by Bonafede, Sapra, Shah, and Desai, along with Widnell and Winner. Kim and Cai took the lead in data collection, assisted by Bonafede and Cappell. Data interpretation was performed by Widnell and Winter, along with the other authors. All authors contributed to the writing and revision of the manuscript.

Migraine and the risk of post-traumatic stress disorder among a cohort of pregnant women

Background

Individually both migraine and post-traumatic stress disorder (PTSD) prevalence estimates are higher among women. However, there is limited data on the association of migraine and PTSD in women during pregnancy.

Methods

We examined the association between migraine and PTSD among women attending prenatal clinics in Peru. Migraine was characterized using the International Classification of Headache Disorders (ICHD)-III beta criteria. PTSD was assessed using the PTSD Checklist-Civilian Version (PCL-C). Multivariable logistic regression analyses were performed to estimate odds ratios (OR) and 95% confidence intervals (CI) after adjusting for confounders.

Results

Of the 2922 pregnant women included, 33.5% fulfilled criteria for any migraine (migraine 12.5%; probable migraine 21.0%) and 37.4% fulfilled PTSD criteria. Even when controlling for depression, women with any migraine had almost a 2-fold increased odds of PTSD (OR: 1.97; 95% CI: 1.64–2.37) as compared to women without migraine. Specifically, women with migraine alone (i.e. excluding probable migraine) had a 2.85-fold increased odds of PTSD (95% CI: 2.18–3.74), and women with probable migraine alone had a 1.61-fold increased odds of PTSD (95% CI: 1.30–1.99) as compared to those without migraine, even after controlling for depression. In those women with both migraine and comorbid depression, the odds of PTSD in all migraine categories were even further increased as compared to those women without migraine.

Conclusion

In a cohort of pregnant women, irrespective of the presence or absence of depression, the odds of PTSD is increased in those with migraine. Our findings suggest the importance of screening for PTSD, specifically in pregnant women with migraine.

Electronic supplementary material

The online version of this article (doi:10.1186/s10194-017-0775-5) contains supplementary material, which is available to authorized users.

Neurovascular contributions to migraine: Moving beyond vasodilation

Migraine is the third most common disease worldwide, the most common neurological disorder, and one of the most common pain conditions. Despite its prevalence, the basic physiology and underlying mechanisms contributing to the development of migraine are still poorly understood and development of new therapeutic targets is long overdue. Until recently, the major contributing pathophysiological event thought to initiate migraine was cerebral and meningeal arterial vasodilation. However, the role of vasodilation in migraine is unclear and recent findings challenge its necessity. While vasodilation itself may not contribute to migraine, it remains possible that vessels play a role in migraine pathophysiology in the absence of vasodilation. Blood vessels consist of a variety of cell types that both release and respond to numerous mediators including growth factors, cytokines, adenosine triphosphate (ATP), and nitric oxide (NO). Many of these mediators have actions on neurons that can contribute to migraine. Conversely, neurons release factors such as norepinephrine and calcitonin gene-related peptide (CGRP) that act on cells native to blood vessels. Both normal and pathological events occurring within and between vascular cells could thus mediate bi-directional communication between vessels and the nervous system, without the need for changes in vascular tone. This review will discuss the potential contribution of the vasculature, specifically endothelial cells, to current neuronal mechanisms hypothesized to play a role in migraine. Hypothalamic activity, cortical spreading depression (CSD), and dural afferent input from the cranial meninges will be reviewed with a focus on how these mechanisms can influence or be impacted by blood vessels. Together, the data discussed will provide a framework by which vessels can be viewed as important potential contributors to migraine pathophysiology, even in light of the current uncertainty over the role of vasodilation in this disorder.

Headache Treatment Before and After the Consultation of a Specialized Centre: A Pharmacoepidemiology Study

Our aim was to study and compare pharmacoepidemiology of headache treatment in two different settings: inside and outside a specialized Centre. We analysed the differences in headache treatment between 612 subjects admitted for the first visit (‘naive’) (F/M: 2.41; mean age = 37.31 ± 14.09 years) and 620 subjects admitted for a control visit (F/M: 3.18; mean age = 44.30 ± 15.37 years) to the Headache Centre of the University of Modena and Reggio Emilia. Most patients suffered from migraine. As acute treatment, on the first visit, 49.4% of them were taking drugs prescribed by a doctor; 41.5% were taking over-the-counter analgesics (OTCAs); 9.1% were not taking any drug. On the control visit, 81.3% of patients were taking prescription drugs; 15.8% OTCAs; 2.9% were not taking drugs (overall chi-square = 139.229, P < 0.001). Non-selective analgesics were the most-used drugs. Triptans were used by 9.1% of ‘naive’ patients and by 31.8% of patients attending for the control visit (Fisher's Z = 7.655, P < 0.001). Nimesulide was the most-used drug. A prophylactic treatment was made by 16.8% of ‘naive’ patients, and by 58.2% of patients admitted to the control visit (Fisher's Z = 12.135, P < 0.001). Antidepressants were the class of drugs most used for prophylaxis. Amitriptyline was the drug for prophylaxis most frequently used by patients attending the control visit, while flunarizine was the most frequently used by ‘naive’ patients. Before being examined in a specialized centre, few patients take prescription drugs, triptans, or prophylactic drugs; specialized care increases the proportion of patients taking prophylactic drugs, and changes the type of acute treatment used into disease-specific medication for headache.

The role of the RhoA/ROCK pathway in gender-dependent differences in gastric smooth muscle contraction

Gender-related differences in various gastric functions and diseases have been reported, with women having a higher prevalence of gastrointestinal disturbances than men. The aim of this study was to investigate sex-dependent differences in activation of the Rho-associated protein kinase (ROCK; RhoA/Rho kinase) pathway and muscle contraction in the stomach using single gastric smooth muscle cells (GSMC) from male and female Sprague-Dawley rats. Expression of ROCK1 and ROCK2 protein and acetylcholine (ACh)-induced activation of RhoA and ROCK were measured using a specifically designed enzyme-linked immunosorbent assay and activity assay kits, respectively. Contraction of a single GSMC was measured by scanning micrometry in the presence or absence of the ROCK inhibitor Y27632 dihydrochloride. ACh-induced activation of RhoA and ROCK and subsequent contraction were greater in male rats than in female rats but neither was related to differences in the expression of ROCK1 or ROCK2 or total RhoA amount. Most important, Y27632 inhibited and abolished differences in ACh-induced contraction in both sexes. In conclusion, increased ACh-induced contraction in the GSMC of male rats is attributable to greater RhoA/ROCK activation independent of differences in the expression of ROCK isoforms or total RhoA.

Migraine incidence in 5 years: a population-based prospective longitudinal study in Turkey

BACKGROUND

The incidence of migraine has been investigated only in a few studies worldwide and it is not known in our country. We, therefore, aimed to estimate the migraine incidence in a previously accomplished population-based prevalence study sample of 5323 individuals in the year 2008.

METHODS

The former Turkish headache prevalence study has been completed as a nationwide, randomized, home-based study of face-to-face examination by physicians trained for headache diagnosis by using ICHD criteria. Five years after this study an optimized survey including 50 questions was performed to estimate the migraine incidence in migraine-free individuals in the previous study, with a 56.4 % responder rate. Two validation studies for this survey were performed prior and after the study each in 100 subjects by comparing the gold standard of expert diagnosis of headache, showing high rate of reliability (Crohnbach alpha: 0.911 and 0.706, respectively).

RESULTS

Migraine incidence was estimated as 2.38 % (2.98 % in women and 1.93 % in men) per year in 2563 migraine-free individuals; if the population at risk is defined as the group without any headaches, the migraine incidence decreased to 1.99 %. The chronic migraine (CM) incidence [without medication overuse (MOH)] was 0.066 % and that of MOH was 0.259 %. We found a significant burden of the disease on the occupational functionality as well as on social and family life, even in the early years of the migraine. The family history of headaches especially in the fathers could be useful to predict new cases of migraine, besides the well-known risk factor, diagnosis of depression, whereas income and education did not seem to relate to migraine onset.

CONCLUSIONS

Our study with a large population-based nation-wide sample, using ICHD-II criteria, with structured headache interviews as well as blinded re-validation of the questionnaire diagnoses showed a 2.38 % incidence rate of migraine in Turkey, higher than most of the other previous reports; a finding which could be related to genetic factors and also to the methodological differences in the study designs. Moreover the incidence of CM was found to be 0.066 %.

Headache in African Americans: An Overlooked Disparity

PURPOSE

The persistence of health disparities in the U.S. has necessitated additional research on race-related health disparities among Americans. Remarkably little research has examined race differences in persons with headache disorders, even though 45 million Americans experience episodic or chronic headaches annually. This review paper examined peer-reviewed publication to examine potential race differences in persons with headache disorders in the areas of headache epidemiology, headache characteristics, psychiatric comorbidity, treatment utilization, and treatment outcomes.

PROCEDURES

A multi-database search (PubMed, Web of Science, PsychlNFO) identified U.S. studies that enrolled racially diverse samples of persons with headache disorders and qualitatively examined potential race-related disparities.

MAIN FINDINGS

Compared to their Caucasian counterparts, African American headache patients are more likely to (i) be diagnosed with comorbid depressive disorders; (ii) report headaches that are more frequent and severe in nature, (iii) have their headaches under-diagnosed and/or undertreated; and (iv) discontinue treatment prematurely, regardless of socioeconomic status.

PRINCIPAL CONCLUSIONS

State of the science treatments for chronic headaches are efficacious; unfortunately, race-related disparities prevent African American headache patients from benefiting from these treatments. Research is needed that enables African Americans with severe headaches to access current headache treatments to alleviate headache burden on the African American community.

The Impact of Post-Traumatic Stress Disorder on the Burden of Migraine: Results From the National Comorbidity Survey-Replication

BACKGROUND

Post-traumatic stress disorder (PTSD) has been linked with migraine in prior studies.

OBJECTIVE

To evaluate the individual and joint burdens of migraine and PTSD in a population-based cohort.

METHODS

The National Comorbidity Survey-Replication (NCS-R) is a general population study conducted in the United States from February 2001-April 2003. PTSD and migraine were assessed, and four groups defined based on their migraine and PTSD status. The four groups included those with no migraine and no PTSD (controls, n=4535), those with migraine and without PTSD (migraine alone, n=236), those with PTSD and without migraine (PTSD alone, n=244), and those with both migraine and PTSD (mig+PTSD, n=68). Logistic and Poisson regression models were used to assess the association between dichotomous/multilevel outcome variables indicating financial, health, and interpersonal burdens and each migraine/PTSD group.

RESULTS

Compared to controls, those with Mig+PTSD were more likely to be in the low poverty index (48% vs 41%, AOR 2.16; CI: 1.10, 4.24) and were less likely to be working for pay or profit in the past week (50% vs 68%, AOR 0.42; CI: 0.24, 0.74) but not those with migraine or PTSD alone. Additionally, the number of days where work quality was cut due to physical or mental health or substance abuse in the past month was greater in all groups compared to controls: (1) migraine alone: mean 2.57 (SEM 0.32) vs mean 1.09 (SEM 0.08) days, ARR=2.39; CI: 2.19, 2.62; (2) PTSD alone: mean 2.43 (SEM 0.33) vs mean 1.09 (SEM 0.08) days, ARR=2.09; CI: 1.91, 2.29; (3) mig+PTSD: mean 8.2 (SEM 0.79) vs 1.09 (SEM 0.08) days, ARR 6.79; CI 6.16, 7.49; and was over 2.5-fold greater in those mig+PTSD than migraine alone (mean 8.0 [SEM 0.79] vs 2.6 days [SEM 0.72], ARR 2.77; CI: 2.45, 3.14). The likelihood of having difficulty getting along or maintaining a social life was also increased in all groups relative to controls: (1) migraine alone: 21% vs 5.4%, AOR 4.20; CI: 2.62, 6.74; (2) PTSD alone: 18% vs 5.4%, AOR 3.40; CI: 2.40, 4.82; (3) Mig+PTSD: 39% vs 5.4%, AOR 9.95; CI: 5.72, 17.32, and was 2-fold greater in those with Mig+PTSD as compared to those with migraine alone (AOR 2.32; CI: 1.15, 4.69).

CONCLUSIONS

These findings support the need for those who treat migraine patients to be aware of the comorbidity with PTSD, as these patients may be particularly prone to adverse financial, health, and interpersonal disease burdens.

Dissecting the association between migraine and stroke

Migraine is a common disabling neurological disorder resulting from excessive cortical excitation and trigeminovascular afferent sensitization. In addition to aberrant neuronal processing, migraineurs are also at significant risk of vascular disease. Consequently, the impact of migraine extends well beyond the ictal headache and includes a well-documented association with acute ischemic stroke, particularly in young women with a history of migraine with aura. The association between migraine and stroke has been acknowledged for 40 years or more. However, examining the pathobiology of this association has become a more recent and critically important undertaking. The diversity of mechanisms underlying the association between migraine and stroke likely reflects the heterogenous nature of this disorder. Vasospasm, endothelial injury, platelet aggregation and prothrombotic states, cortical spreading depression, carotid dissection, genetic variants, and traditional vascular risk factors have been offered as putative mechanisms involved in migraine-related stroke risk. Assimilating these seemingly divergent pathomechanisms into a cogent understanding of migraine-related stroke will inform future studies and the development of new strategies for the prevention and treatment of migraine and stroke.

Robust and Accurate Modeling Approaches for Migraine Per-Patient Prediction from Ambulatory Data

Migraine is one of the most wide-spread neurological disorders, and its medical treatment represents a high percentage of the costs of health systems. In some patients, characteristic symptoms that precede the headache appear. However, they are nonspecific, and their prediction horizon is unknown and pretty variable; hence, these symptoms are almost useless for prediction, and they are not useful to advance the intake of drugs to be effective and neutralize the pain. To solve this problem, this paper sets up a realistic monitoring scenario where hemodynamic variables from real patients are monitored in ambulatory conditions with a wireless body sensor network (WBSN). The acquired data are used to evaluate the predictive capabilities and robustness against noise and failures in sensors of several modeling approaches. The obtained results encourage the development of per-patient models based on state-space models (N4SID) that are capable of providing average forecast windows of 47 min and a low rate of false positives.

Importance and hurdles to drug discovery for neurological disease

This is a critical time in neurotherapeutics. The prevalence of neurological disease, such as dementia, stroke, and peripheral neuropathy, is large and growing consequent to the aging population. The personal and societal impact of these disorders is enormous, and the number of novel therapies in the pipeline for these disorders has been contracting. Support for the development of neurotherapies must continue from the bench to their ultimate place at the bedside. Academic medicine must continue to play a critical role, in league with industry and government, in the development of novel neurotherapies desperately needed by an ever-expanding population. Critical steps include the identification and adoption of reliable, valid, and reproducible biomarkers to serve as primary endpoints in clinical trials of neurological disease.

The epidemiology of primary headache disorders in Zambia: a population-based door-to-door survey

Background

Little is known of the epidemiology of primary headache disorders in sub-Saharan Africa. We performed a population-based survey in Zambia using methods previously tested in multiple other countries.

Methods

This cross-sectional survey was conducted by visiting households unannounced, using cluster-randomized sampling, in the mostly urban Lusaka Province and mostly rural Southern Province. Within clusters, households were selected randomly, as was one adult member (18-65 years old) of each selected household. A structured questionnaire, translated into the local languages, was administered face-to-face by trained interviewers. Demographic enquiry was followed by diagnostic questions based on ICHD-II criteria. A random sub-sample of participants were invited for subsequent physician-interview to validate the diagnostic part of the questionnaire.

Results

Of 1,134 eligible household members contacted, 1,085 (450 male, 887 urban) consented to interview (refusal rate 4.3%). Others who had been selected but remained unavailable on three visits were not counted as refusals since their reasons were unknown, but gave rise to gender biases, being mostly male in urban areas and mostly female in rural areas. Statistical correction was applied. Adjusted for gender and habitation (urban/rural), the 1-year prevalence of any headache was 61.6%, of migraine 22.9%, of tension-type headache (TTH) 22.8%, of headache on ≥15 days/month 11.5% and of probable medication-overuse headache (pMOH) 7.1%. The adjusted point-prevalence of any headache (headache yesterday) was 19.1%. There was a small proportion (5.3%) of unclassified headache, some of which may have been secondary. The overwhelmingly strong association was between urban dwelling and pMOH (OR: 8.6; P=0.0001), with an urban prevalence of 14.5% (gender-adjusted). Validation of the questionnaire was limited by participants’ reluctance to present for physician review, substantial delays in doing so and major self-selection bias among those who did. These were unavoidable problems in resource-limited Zambia.

Conclusions

Primary headache disorders, common in high-income countries, are at least as prevalent in Zambia, a sub-Saharan African country. The selectively urban problem of pMOH seems likely to reflect ready availability of non-prescription analgesics, without easy access to professional health care for headache or any focused public-health education regarding correct usage of analgesics or the dangers of their overuse.

A review of the pharmacoeconomics of eletriptan for the acute treatment of migraine

Migraine is a commonly occurring, chronic disorder that can cause significant disability. Eletriptan, a selective serotonin 5-hydroxytryptamine 1 receptor subtype B/D (5-HT_1B/1D) agonist, is a clinically effective treatment for moderate to severe migraine. The objective of this literature review was to summarize the available data on the pharmacoeconomics of eletriptan relative to other triptans. Articles meeting the following three criteria were included in the review: 1) contained pharmacoeconomic data on a marketed dose of eletriptan; 2) included data on at least one other comparator triptan; and 3) was in English. A MEDLINE^® search yielded a total of eight studies (from the European Union [n=5] and from the USA [n=3]) across multiple regions. Seven of the studies examined the pharmacoeconomics of eletriptan relative to other triptans, and a further study examined the health care costs of eletriptan 40 mg versus sumatriptan 100 mg. Eletriptan 40 mg was among a group of triptans, including rizatriptan 10 mg and almotriptan 12.5 mg, demonstrating the greatest cost-effectiveness. This result held across different definitions of efficacy (2 hours pain-free, sustained pain-free, and sustained pain-free with no adverse events) and also held when cost-effectiveness models accounted for second doses and use of rescue medication, management of adverse events, and productivity loss, in addition to drug acquisition costs. Only limited head-to-head comparator data were available. The majority of pharmacoeconomic studies utilized the same set of efficacy and/or tolerability data, and indirect costs were rarely included despite the fact that the majority of per capita migraine costs are attributable to indirect costs. In summary, although the market is now dominated by generics, eletriptan 40 mg is among the most clinically and cost-effective oral triptans available for the management of acute migraine. Increased effectiveness/efficacy of eletriptan may necessitate a lesser need for other migraine treatments and/or switching to other triptans.

The psychometric properties of the persian migraine-specific quality of life questionnaire version 2.1 in episodic and chronic migraines

Background. Migraine-specific quality of life (MSQ) is a valid and reliable questionnaire. Linguistic validation of Persian MSQ questionnaire, analysis of psychometric properties between chronic and episodic migraine patients, and capability of MSQ to differentiate between chronic and episodic migraines were the aims of this study. Method. Participants were selected from four different neurology clinics that were diagnosed as chronic or episodic migraine patients. Baseline data included information from MSQ v. 2.1, MIGSEV, SF-36, and symptoms questionnaire. At the third week from the baseline, participants filled out MSQ and MIGSEV. Internal consistency (Cronbach alpha) and test-retest reproducibility (intraclass correlation coefficients) were used to assess reliability. Convergent and discriminant validities were also assessed. Results. A total of 106 participants were enrolled. Internal consistencies of MSQ among all patients, chronic and episodic migraines, were 0.92, 0.91, and 0.92, respectively. Test-retest correlation of MSQ dimensions between visits 1 and 2 varied from 0.41 to 0.50. Convergent, item discriminant, and discriminant validities were approved. In all visits MSQ scores were lower in chronic migraine than episodic migraine; however, the difference was not statistically significant. Conclusion. Persian translation of MSQ is consistent with original version of MSQ in terms of psychometric properties in both chronic and episodic migraine patients.

Migraine headache is present in the aura phase: a prospective study

OBJECTIVES

Migraine aura is commonly considered to be a distinct phase of a migraine attack that precedes headache. The objective of the study was to examine a large number of prospectively recorded attacks of migraine with aura and determine the timing of headache and other migraine symptoms relative to aura.

METHODS

As part of a clinical trial we collected prospective data on the time course of headache and other symptoms relative to the aura. Patients (n = 267) were enrolled from 16 centers, and asked to keep a headache diary for 1 month (phase I). They were asked to record headache symptoms as soon as possible after aura began and always within 1 hour of aura onset. A total of 456 attacks were reported during phase I by 201 patients. These patients were then randomized and included in phase II, during which a total of 405 attacks were reported in 164 patients. In total, we present data from 861 attacks of migraine with aura from 201 patients.

RESULTS

During the aura phase, the majority of attacks (73%) were associated with headache. Other migraine symptoms were also frequently reported during the aura: nausea (51%), photophobia (88%), and photophobia (73%). During the first 15 minutes within the onset of aura, 54% of patients reported headache fulfilling the criteria for migraine.

CONCLUSION

Our results indicate that headaches as well as associated migraine symptoms are present early, during the aura phase of the migraine attack in the majority of patients.

Brain-derived neurotrophic factor in primary headaches

Brain derived neurotrophic factor (BDNF) is associated with pain modulation and central sensitization. Recently, a role of BDNF in migraine and cluster headache pathophysiology has been suspected due to its known interaction with calcitonin gene-related peptide. Bi-center prospective study was done enrolling four diagnostic groups: episodic migraine with and without aura, episodic cluster headache, frequent episodic tension-type headache, and healthy individuals. In migraineurs, venous blood samples were collected twice: outside and during migraine attacks prior to pain medication. In cluster headache patients serum samples were collected in and outside cluster bout. Analysis of BDNF was performed using enzyme-linked immunosorbent assay technique. Migraine patients revealed significantly higher BDNF serum levels during migraine attacks (n = 25) compared with headache-free intervals (n = 53, P < 0.01), patients with tension-type headache (n = 6, P < 0.05), and healthy controls (n = 22, P < 0.001). There was no significant difference between patients with migraine with aura compared with those without aura, neither during migraine attacks nor during headache-free periods. Cluster headache patients showed significantly higher BDNF concentrations inside (n = 42) and outside cluster bouts (n = 24) compared with healthy controls (P < 0.01, P < 0.05). BDNF is increased during migraine attacks, and in cluster headache, further supporting the involvement of BDNF in the pathophysiology of these primary headaches.

Understanding migraine through the lens of maladaptive stress responses: a model disease of allostatic load

The brain and body respond to potential and actual stressful events by activating hormonal and neural mediators and modifying behaviors to adapt. Such responses help maintain physiological stability ("allostasis"). When behavioral or physiological stressors are frequent and/or severe, allostatic responses can become dysregulated and maladaptive ("allostatic load"). Allostatic load may alter brain networks both functionally and structurally. As a result, the brain's responses to continued/subsequent stressors are abnormal, and behavior and systemic physiology are altered in ways that can, in a vicious cycle, lead to further allostatic load. Migraine patients are continually exposed to such stressors, resulting in changes to central and peripheral physiology and function. Here we review how changes in brain states that occur as a result of repeated migraines may be explained by a maladaptive feedforward allostatic cascade model and how understanding migraine within the context of allostatic load model suggests alternative treatments for this often-debilitating disease.

The complex actions of sumatriptan on rat dural afferents

AIM

To test the hypothesis that the clinical efficacy of triptans reflects convergent modulation of ion channels also involved in inflammatory mediator (IM)-induced sensitization of dural afferents.

METHODS

Acutely dissociated retrogradely labeled rat dural afferents were studied with whole cell and perforated patch techniques in the absence and presence of sumatriptan and/or IM (prostaglandin E2, bradykinin, and histamine).

RESULTS

Sumatriptan dose-dependently suppressed voltage-gated Ca²⁺ currents. Acute (2 min) sumatriptan application increased dural afferent excitability and occluded further IM-induced sensitization. In contrast, pre-incubation (30 min) with sumatriptan had no influence on dural afferent excitability and partially prevented IM-induced sensitization of dural afferents. The sumatriptan-induced suppression of voltage-gated Ca²⁺ currents and acute sensitization and pre-incubation-induced block of IM-induced sensitization were blocked by the 5-HT(1D) antagonist BRL 15572. Pre-incubation with sumatriptan failed to suppress the IM-induced decrease in action potential threshold and overshoot (which results from modulation of voltage-gated Na⁺ currents) and activation of Cl⁻ current, and had no influence on the Cl⁻ reversal potential. However, pre-incubation with sumatriptan caused a dramatic hyperpolarizing shift in the voltage dependence of K⁺ current activation.

DISCUSSION

These results indicate that although the actions of sumatriptan on dural afferents are complex, at least two distinct mechanisms underlie the antinociceptive actions of this compound. One of these mechanisms, the shift in the voltage dependence of K⁺ channel activation, may suggest a novel strategy for future development of anti-migraine agents.

Headaches related to psychoactive substance use

AIM

To investigate a possible association between headache and psychoactive substance use.

METHODS

1055 psychoactive substance abusers were consecutively admitted. All patients filled out a detailed headache questionnaire and 1015 patients were included.

RESULTS

Twenty seven percent of patients reported having headache. Eighteen percent of patients reported having headache attributed to a substance or its withdrawal and 1.4% had unclassified headache. The most commonly used substances were cannabis (80.5%), alcohol (74.6%), methylamphetamine (18.7%), benzodiazepine (10.4%), volatile solvent (5.8%), cocaine (4.4%), heroin (2.1%), opioids (0.5%), and other substances (1.7%). Fifteen patients reported that onset of headache occurred prior to onset of substance use, while 94.5% had headaches occurred after substance abuse. A higher incidence of headache was found in the benzodiazepine, methylamphetamine, cocaine, heroin, volatile solvent abusers. Seventy-eight percent of headache patients have never sought help from a physician despite the severity and frequency of headache.

CONCLUSIONS

In our study, the prevalence of headache among all psychoactive substance abusers was 26.9%. Although this is one-group study without any comparison with non-addict population and associational data must be interpreted with caution, the results of this study indicate a possible relationship may exist between headache and substance use since 94.5% of substance users described headaches after the onset of substance use. The younger start and the longer duration of cannabis use caused the higher incidence of headache, but this correlation was not observed in other substance use. Migraine was far more prevalent in the abusers than in previously reported community populations.

The International Burden of Migraine Study (IBMS): Study design, methodology, and baseline cohort characteristics

Objective: To describe a survey methodology to evaluate headache characteristics and burden and to present baseline characteristics for the international cohort of survey participants.

Methods: A targeted, web-based methodology was used to recruit and survey subjects with migraine in 10 countries. Based on reported symptoms, subjects meeting ICHD-2 criteria for migraine were included; eligible subjects were classified as chronic (≥ 15 headache days per month) or episodic (< 15 headache days per month). Outcomes included sociodemographic and clinical characteristics, resource utilization, disability, health-related quality of life, anxiety, depression and productivity.

Results: Of 23,312 survey respondents, 11,897 were eligible and 9715 (81.7%) completed the survey; subjects were 81.5% female; 5.7% ( n = 555) had chronic migraine.

Conclusions: This is the first large international cohort of persons with chronic and episodic migraine studied using a web-based approach, a methodology well suited to the study of the burden of migraines.

Ethical problems arising from the use of placebo in clinical trials with drugs for migraine. Their analysis by the moral deliberation method

INTRODUCTION

Migraine is characterised as episodes of headache plus a variety of accompanying symptoms. Its pharmacological control remains unsatisfactory for some patients. The use of placebo in drug clinical trials on migraine commonly leads to numerous ethical uncertainties.

METHODS

The purpose of this paper is to illustrate how the deliberation method helps in analysing the issues and finding solutions to selected ethical problems. Ethical decisions that try to solve conflicts arising from placebo use in clinical trials may be adopted using the moral deliberation method. Thus, the conflict is systematically assessed by identifying the following: Relevant facts; Values in conflict; Duties, or in other words, possible courses of action. Moral duty is following the optimal course of action. To identify this, it is recommended to state extreme courses of action, then intermediate courses of action, and then to proceed to the optimal course(s) of action.

RESULTS AND CONCLUSIONS

In this paper, the application of this method is shown in several conflicting situations arising in two placebo-controlled clinical trials with drugs under development for the prophylaxis and acute treatment of migraine.

One-year prevalence of migraine in Spain: A nationwide population-based survey

Aim

The purpose of the study was to estimate the one-year prevalence of migraine among a population-based sample of Spanish adults.

Method

Men and women aged 18-65 years were selected at random according to quotas for age, sex, size of habitat (10,000 inhabitants, 10,001–50,000 inhabitants, 50,001 −200,000 inhabitants and 200,000 inhabitants) and residence proportional to the population size of the geographical location. A random-digit-dial, computer-assisted telephone interview (CATI) survey was conducted between April and July 2006. The 2004 International Headache Society operational diagnostic criteria were applied.

Results

From a total of 70,692 telephone calls and 26,255 (31.7%) valid contacts, 5,668 (21.6%) respondents completed the CATI survey. A total of 476 subjects (8.4%, 95% confidence interval [CI] 7.7-9.1%) with strict migraine and 236 with probable migraine (4.2%, 95% CI 3.7-4.7%) were recorded. The 1-year prevalence of total migraine (N = 712) was 12.6% (95% CI 11.6-13.6) (17.2% in females, 8.0% in males). The prevalence rates showed significant geographic variations, from 7.6% in Navarra to 18% in the Canary Islands. One-half of the subjects had migraine with aura. One-third of subjects were never diagnosed for migraine.

Conclusions

The one-year prevalence of migraine in Spain is 12.6%, with a prevalence of migraine with and without aura of 8.4% and probable migraine of 4.2%. These findings add data to the current understanding of migraine.

Clinical and economic comparison of frovatriptan versus other oral triptans in the treatment of acute migraine in the real-world setting

Triptans (serotonin 5-HT(1B/1D) receptor agonists) such as frovatriptan have been shown to be highly effective and well tolerated in the treatment of patients with acute migraine. However, the large number of available triptans has led to the issue of how best to decide which triptan should be prescribed at an individual patient level. This review focuses on frovatriptan and highlights parameters that affect oral triptan choice, discusses the results of several open-label clinical and post-marketing surveillance studies of frovatriptan, and compares these naturalistic data with those from similar studies of other oral triptans. Efficacy data obtained from these trials are used to compare costs of treating migraine with frovatriptan and other oral triptans in four European countries. Studies of triptans in migraine have used several outcomes deemed important to patients, including complete pain relief, absence of recurrence, rapid onset of action, no side effects, restoration of functional ability, improvements in quality of life, and cost. In contrast to indirect evidence from some individual randomized, double-blind studies, results from open-label naturalistic studies and a meta-analysis of 31 placebo-controlled efficacy studies suggest that frovatriptan is associated with a lower rate of migraine recurrence than with other triptans in a real-world clinical setting (17% for frovatriptan 2.5 mg vs 23-40% for other triptans in the meta-analysis). It is likely that this may be due to the terminal elimination half-life of this agent (about 26 hours), which is longer than that of other triptans. Naturalistic studies indicate that the long duration of action of frovatriptan appears to confer other benefits such as greater patient satisfaction, with over 90% of patients and doctors rating frovatriptan therapy as 'very good' or 'good'. The cost of treatment with different triptans based on the number of tablets required per episode varies widely in each of the four countries analysed (Great Britain Pound 4.95-7.98 in France, Great Britain Pound 6.78-12.58 in Germany, Great Britain Pound 4.32-9.73 in the UK and Great Britain Pound 6.69-10.36 in Italy, based on lowest possible costs for branded versions in 2008) due to differences in both the acquisition costs of these agents and in the headache recurrence rates. Frovatriptan compares favourably with other available triptans with regard to cost per migraine attack on this basis, although head-to-head studies are required to confirm these data. The low rate of headache recurrence with frovatriptan compared with other oral triptans, and the associated lower treatment costs, deserve consideration when choosing an oral triptan for the treatment of patients with acute migraine.

Migraine: an endemic disease inside the blood–brain barrier

Migraine is a complex neurological disorder that in recent years has received more and more attention. Knowledge regarding this primary headache has increased substantially, both with respect to its pathogenesis and how to effectively treat its symptoms. Over the years, the proposed location of the onset of migraine has moved from the periphery of the nervous system toward deeper parts of the brain. Migraine can be viewed as an inherited failure of trigeminal sensory processing with abnormal neuronal excitability in the trigeminal nucleus caudalis, which, in turn, causes central sensitization and amplification of the pain. Increased activation of the trigeminal nerve during a migraine attack causes release of the calcitonin gene-related peptide (CGRP) inside and outside the BBB. Within the CNS, CGRP promotes trigeminal sensory input and facilitates central sensitization. The future introduction of CGRP antagonists in clinical practice could represent significant progress for acute migraine therapy.

Role of the oestrogen receptors GPR30 and ERalpha in peripheral sensitization: relevance to trigeminal pain disorders in women

Oestrogen increases facial allodynia through its actions on activation of the MAPK extracellular-signal regulated kinase (ERK) in trigeminal ganglion neurons. This goal of study was to determine which oestrogen receptor is required for behavioural sensitization. Immunohistochemical studies demonstrated the presence of oestrogen receptor alpha (ERalpha) in nuclei of larger neurons and cytoplasm of smaller neurons, and the novel oestrogen receptor G-protein coupled receptor 30 (GPR30) in small diameter neurons that also contained peripherin, a marker of unmyelinated C-fibres. Specific agonists for ERalpha (PPT) and GPR30 (G-1), but not ERbeta (DPN), activated ERK in trigeminal ganglion neurons in vitro. Both G-1 and PPT treatment increased allodynia after CFA injections into the masseter of ovariectomized Sprague-Dawley rats. Treatment with oestrogen increased expression of ERalpha but not GPR30, while masseter inflammation increased GRP30 but not ERalpha. Differential modulation of these ERK-coupled receptors by oestrogen and inflammation may play a role in painful episodes of temporomandibular disorder and migraine.

Development and validation of a pharmacy migraine questionnaire to assess suitability for treatment with a triptan

A questionnaire (Migraine Questionnaire; MQ) was developed to help pharmacists identify consumers with migraine suitable for non-prescription treatment with a triptan. Adults, who knew or thought that they had migraine, participated in three, sequential, community-based studies to validate the MQ. Overall, 1,353 subjects completed independent assessments with a pharmacist and a clinician (reference standard). The accuracy of the pharmacist assessment of suitability for a triptan was compared with the clinician assessment. Clinicians using their standard practice determined that triptan therapy was suitable in 76.8% of cases compared with 48.8% for pharmacists using the MQ. The lack of concordance between pharmacists and clinicians in the false-positive cases (n = 113 of 660 subjects considered suitable for triptan by the pharmacists) usually related to headache diagnosis (57.5%), not safety aspects. The MQ is an effective tool for pharmacists to guide appropriate recommendation of a non-prescription triptan for migraine.

Normobaric and hyperbaric oxygen therapy for migraine and cluster headache

BACKGROUND

Migraine and cluster headaches are severe and disabling. Migraine affects up to 18% of women, while cluster headaches are much less common (0.2% of the population). A number of acute and prophylactic therapies are available. Hyperbaric oxygen therapy (HBOT) is the therapeutic administration of 100% oxygen at environmental pressures greater than one atmosphere, while normobaric oxygen therapy (NBOT) is oxygen administered at one atmosphere.

OBJECTIVES

To assess the safety and effectiveness of HBOT and NBOT for treating and preventing migraine and cluster headaches.

SEARCH STRATEGY

We searched the following in May 2008: CENTRAL, MEDLINE, EMBASE, CINAHL, DORCTIHM and reference lists from relevant articles. Relevant journals were hand searched and researchers contacted.

SELECTION CRITERIA

Randomised trials comparing HBOT or NBOT with one another, other active therapies, placebo (sham) interventions or no treatment in patients with migraine or cluster headache.

DATA COLLECTION AND ANALYSIS

Three reviewers independently evaluated study quality and extracted data.

MAIN RESULTS

Nine small trials involving 201 participants were included. Five trials compared HBOT versus sham therapy for acute migraine, two compared HBOT to sham therapy for cluster headache and two evaluated NBOT for cluster headache. Pooling of data from three trials suggested that HBOT was effective in relieving migraine headaches compared to sham therapy (relative risk (RR) 5.97, 95% confidence interval (CI) 1.46 to 24.38, P = 0.01). There was no evidence that HBOT could prevent migraine episodes, reduce the incidence of nausea and vomiting or reduce the requirement for rescue medication. There was a trend to better outcome in a single trial evaluating HBOT for the termination of cluster headache (RR 11.38, 95% CI 0.77 to 167.85, P = 0.08), but this trial had low power.NBOT was effective in terminating cluster headache compared to sham in a single small study (RR 7.88, 95% CI 1.13 to 54.66, P = 0.04), but not superior to ergotamine administration in another small trial (RR 1.17, 95% CI 0.94 to 1.46, P = 0.16). Seventy-six per cent of patients responded to NBOT in these two trials. No serious adverse effects of HBOT or NBOT were reported.

AUTHORS' CONCLUSIONS

There was some evidence that HBOT was effective for the termination of acute migraine in an unselected population, and weak evidence that NBOT was similarly effective in cluster headache. Given the cost and poor availability of HBOT, more research should be done on patients unresponsive to standard therapy. NBOT is cheap, safe and easy to apply, so will probably continue to be used despite the limited evidence in this review.