Field testing alternative criteria for chronic migraine

The evolving classifications and epidemiological challenges surrounding chronic migraine and medication overuse headache: a review

Changes in diagnostic criteria, for example, the various International Classification of Headache Disorders criteria, would lead to changes in the outcomes of epidemiological studies. International Classification of Headache Disorders-1 was based mainly on expert opinion, yet most of the diagnostic criteria were reliable and valid, but it did not include chronic migraine. In its second version, the classification introduced chronic migraine, but this diagnosis resembled more a high-frequency migraine rather than the actual migraine transformation process. It also introduced medication overuse headache, but it necessitated analgesic withdrawal and subsequent headache improvement to be diagnosed as such. Hence patients having medication overuse headache could only be diagnosed in retrospect, which was an awkward situation. Such restrictive criteria for chronic migraine and medication overuse headache omitted a high proportion of patients. International Classification of Headache Disorders-3 allows a diagnosis of medication overuse headache due to combination analgesics if taken for at least 10 days per month for more than three months. Hence the prevalence rate of medication overuse headache and chronic migraine can increase compared to the previous version of the headache classification. Different criteria have been used across studies to identify chronic migraine and medication overuse headache, and therefore the information acquired from previous studies using earlier criteria becomes uncertain. Hence much epidemiological research would need to be interpreted cautiously or repeated with the most updated criteria, since the subjects in studies that apply the latest criteria may be phenotypically different from those in older studies.

The International Classification of Headache Disorders Revised Criteria for Chronic Migraine—Field Testing in a Headache Specialty Clinic

In the absence of a biological marker and expert consensus on the best approach to classify chronic migraine (CM), recent revised criteria for this disease has been proposed by the Headache Classification Committee of the International Headache Society. This revised criteria for CM is now presented in the Appendix. Herein we field test the revised criteria for CM. We included individuals with transformed migraine with or without medication overuse (TM+ and TM-), according to the criteria proposed by Silberstein and Lipton, since this criterion has been largely used before the Second Edition of the International Classification of the Headache Disorders (ICHD-2). We assessed the proportion of subjects that fulfilled ICHD-2 criteria for CM or probable chronic migraine with probable medication overuse (CM+), as well as the revised ICHD-2 (ICHD-2R) criteria for CM (≥15 days of headache, ≥8 days of migraine or migraine-specific acute medication use—ergotamine or triptans). We also tested the ICHD-2R vs. three proposals. In proposal 1, CM/CM+ would require at least 15 days of migraine or probable migraine per month. Proposal 2 required ≥15 days of headache per month and at least 50% of these days were migraine or probable migraine. Proposal 3 required ≥15 days of headache and at least 8 days of migraine or probable migraine per month. Of the 158 patients with TM-, just 5.6% met ICHD-2 criteria for CM. According to the ICHD-2R, a total of 92.4% met criteria for CM ( P < 0.001 vs. ICHD-2). The ICHD-2R criterion performed better than proposal 1 (47.8% of agreement, P < 0.01) and was not statistically different from proposals 2 (87.9%) and 3 (94.9%). Subjects with TM+ should be classified as medication overuse headache (MOH), and not CM+, according to the ICHD-2R. Nonetheless, we assessed the proportion of them who had ≥8 days of migraine per month. Of the 399 individuals with TM+, just 10.2% could be classified as CM+ in the ICHD-2. However, most (349, 86.9%) had ≥8 days of migraine per month and could be classified as MOH and probable CM in the ICHD-2R ( P < 0.001 vs. ICHD-2). We conclude that the ICHD-2R addresses most of the criticism towards the ICHD-2 and should be adopted in clinical practice and research. In the population where use of specific acute migraine medications is less common, the agreement between ICHD-2R CM and TM may be less robust.

Field-testing of the ICHD-3 beta/proposed ICD-11 diagnostic criteria for migraine with aura

INTRODUCTION

In 2013 the International Headache Society published the third International Classification of Headache Disorders beta-version, ICHD-3 beta. Its structure is identical to that of the present proposed version of the International Classification of Diseases (ICD-11), although slightly abbreviated to fulfill the needs of ICD-11. In the following, only ICHD-3 beta is mentioned, but findings regarding the validity of ICHD-3 beta categories are equally relevant to the forthcoming ICD-11. Here we field-tested the criteria for 1.2 migraine with aura (MA), 1.2.1 migraine with typical aura (MTA), 1.2.3 hemiplegic migraine, 1.2.2 migraine with brainstem aura, and the alternative criteria A1.2 MA and A1.2.1 MTA.

METHODS

Clinical characteristics were systematically and prospectively collected from patients with 1.2.1 MTA, 1.2.4 familial hemiplegic migraine (FHM), 1.2.5 sporadic hemiplegic migraine (SHM) and 1.2.6 basilar-type migraine according to ICHD-2 in a cross-sectional study design. A database of 2464 patients with 1.1 migraine without aura and 1.2 migraine with non-hemiplegic aura and a database of 252 hemiplegic migraine patients (1.2.4 FHM or 1.2.5 SHM) was collected. We used SPSS 20 for Windows 8.0 for the statistical analysis.

RESULTS

All ICHD-2 patients fulfilled ICHD-3 beta criteria for 1.2 MA. The ICHD-3 beta criteria for 1.2.1 MTA were more sensitive than ICHD-2 and ICHD-3 beta alternative criteria; they resulted in fewer probable MA diagnoses. Too many patients fulfilled ICHD-2 and ICHD-3 beta criteria for 1.2.2 migraine with brainstem aura. ICHD-3 beta criteria for 1.2.4 FHM and 1.2.5 SHM both comply with ICHD-2.

CONCLUSION

The new criteria in ICHD-3 beta/proposed ICD-11 for 1.2 MA, 1.2.1 MTA, 1.2.3.1 FHM and 1.2.3.2 SHM have more desirable properties than ICHD-2 and the ICHD-3 beta alternative criteria. The criteria for 1.2.2 migraine with brainstem aura should be more restrictive.

Chronic daily headache in Korea: prevalence, clinical characteristics, medical consultation and management

Background and Purpose

Chronic daily headache (CDH) is a commonly reported reason for visiting hospital neurology departments, but its prevalence, clinical characteristics, and management have not been well documented in Korea. The objective of this study was to characterize the 1-year prevalence, clinical characteristics, medical consultations, and treatment for CDH in Korea.

Methods

The Korean Headache Survey (KHS) is a nationwide descriptive survey of 1507 Korean adults aged between 19 and 69 years. The KHS investigated headache characteristics, sociodemographics, and headache-related disability using a structured interview. We used the KHS data for this study.

Results

The 1-year prevalence of CDH was 1.8% (95% confidence interval, 1.1-2.5%), and 25.7% of the subjects with CDH met the criteria for medication overuse. Two-thirds (66.7%) of CDH subjects were classified as having chronic migraine, and approximately half of the CDH subjects (48.1%) reported that their headaches either substantially or severely affected their quality of life. Less than half (40.7%) of the subjects with CDH reported having consulted a doctor for their headaches and 40.7% had not received treatment for their headaches during the previous year.

Conclusions

The prevalence of CDH was 1.8% and medication overuse was associated with one-quarter of CDH cases in Korea. Many subjects with CDH do not seek medical consultation and do not receive appropriate treatment for their headaches.

Psychiatric comorbidities of episodic and chronic migraine

Migraine is a prevalent disabling neurological disorder associated with a wide range of medical and psychiatric comorbidities. Population- and clinic-based studies suggest that psychiatric comorbidities, particularly mood and anxiety disorders, are more common among persons with chronic migraine than among those with episodic migraine. Additional studies suggest that psychiatric comorbidities may be a risk factor for migraine chronification (i.e., progression from episodic to chronic migraine). It is important to identify and appropriately treat comorbid psychiatric conditions in persons with migraine, as these conditions may contribute to increased migraine-related disability and impact, diminished health-related quality of life, and poor treatment outcomes. Here, we review the current literature on the rates of several psychiatric comorbidities, including depression, anxiety, and post-traumatic stress disorder, among persons with migraine in clinic- and population-based studies. We also review the link between physical, emotional, and substance abuse, psychiatric disorders, and migraine. Finally, we review the data on psychiatric risk factors for migraine chronification and explore theories and evidence underlying the comorbidity between migraine and these psychiatric disorders.

Chronic migraine classification: current knowledge and future perspectives

In the field of so-called chronic daily headache, it is not easy for migraine that worsens progressively until it becomes daily or almost daily to find a precise and universally recognized place within the current international headache classification systems. In line with the 2006 revision of the second edition of the International Classification of Headache Disorders (ICHD-2R), the current prevailing opinion is that this headache type should be named chronic migraine (CM) and be characterized by the presence of at least 15 days of headache per month for at least 3 consecutive months, with headache having the same clinical features of migraine without aura for at least 8 of those 15 days. Based on much evidence, though, a CM with the above characteristics appears to be a heterogeneous entity and the obvious risk is that its definition may be extended to include a variety of different clinical entities. A proposal is advanced to consider CM a subtype of migraine without aura that is characterized by a high frequency of attacks (10-20 days of headache per month for at least 3 months) and is distinct from transformed migraine (TM), which in turn should be included in the classification as a complication of migraine. Therefore, CM should be removed from its current coding position in the ICHD-2 and be replaced by TM, which has more restrictive diagnostic criteria (at least 20 days of headache per month for at least 1 year, with no more than 5 consecutive days free of symptoms; same clinical features of migraine without aura for at least 10 of those 20 days).

Chronic daily headache in the pediatric population

Very limited long-term follow-up data exist for the population of children and adolescents with chronic daily headache (CDH). One abstracted report discusses short-term follow-up on 24 adolescents (peak age 13 years) with CDH; in a 6-month follow-up, more than 50% experienced a reduction of 75% or more in headache frequency, and one third showed an improvement of greater than 90% in headache frequency. A wide variety of preventive agents were used, but amitriptyline and topiramate provided the largest percentage of successful outcomes. With an improving classification scheme, we have the possibility of using multicenter studies to elucidate whether the clinical patterns seen by experienced observers translate into rational differentiation of treatment approaches. If the entities of CDH are, indeed, different, then therapeutic, prophylactic, and behavioral trials could guide us in offering a more evidence-based approach to the treatment of this fascinating, yet sometimes debilitating condition.

Chronic migraine: Classification and comparisons

Objective: The objective of our study was to field test different chronic migraine (CM) criteria and compare CM epidemiological profiles, which include demographic, personal, and lifestyle characteristics, with high-frequency episodic migraine (HFEM) and low-frequency episodic migraine (LFEM).

Methods: Questionnaires were mailed to a random sample of 18,000 18–65-year-olds in demographically diverse regions of Germany. The epidemiological data for the three classifications of CM, LFEM and HFEM were assessed using descriptive statistics, Pearson Chi-square, and analysis of variance tests.

Results: Among 9350 respondents, CM_I was the most restrictive ( N = 37, 0.4%), followed by CM_II ( N = 45, 0.5%) and CM_III ( N = 185, 2.0%). CM groups did not differ in distribution by age, gender, body mass index, education or smoking and alcohol consumption. Compared to those with LFEM and HFEM, those with CM (CM_III) had significantly different epidemiological profiles.

Conclusions: CM prevalence varies by case definition. The epidemiological profiles of the three CM groups are similar but differ significantly from those of HFEM and LFEM. Optimal definitions for clinical practice and epidemiological research require additional field testing.

OnabotulinumtoxinA for treatment of chronic migraine: pooled results from the double-blind, randomized, placebo-controlled phases of the PREEMPT clinical program

OBJECTIVE

To assess the efficacy, safety, and tolerability of onabotulinumtoxinA (BOTOX) as headache prophylaxis in adults with chronic migraine.

BACKGROUND

Chronic migraine is a prevalent, disabling, and undertreated neurological disorder. Few preventive treatments have been investigated and none is specifically indicated for chronic migraine.

METHODS

The 2 multicenter, pivotal trials in the PREEMPT: Phase 3 REsearch Evaluating Migraine Prophylaxis Therapy clinical program each included a 24-week randomized, double-blind phase followed by a 32-week open-label phase (ClinicalTrials.gov identifiers NCT00156910, NCT00168428). Qualified patients were randomized (1:1) to onabotulinumtoxinA (155-195 U) or placebo injections every 12 weeks. Study visits occurred every 4 weeks. These studies were identical in design (eg, inclusion/exclusion criteria, randomization, visits, double-blind phase, open-label phase, safety assessments, treatment), with the only exception being the designation of the primary and secondary endpoints. Therefore, the predefined pooling of the results was justified and performed to provide a complete overview of between-group differences in efficacy, safety, and tolerability that may not have been evident in individual studies. The primary endpoint for the pooled analysis was mean change from baseline in frequency of headache days at 24 weeks. Secondary endpoints were mean change from baseline to week 24 in frequency of migraine/probable migraine days, frequency of moderate/severe headache days, total cumulative hours of headache on headache days, frequency of headache episodes, frequency of migraine/probable migraine episodes, frequency of acute headache pain medication intakes, and the proportion of patients with severe (> or =60) Headache Impact Test-6 score at week 24. Results of the pooled analyses of the 2 PREEMPT double-blind phases are presented.

RESULTS

A total of 1384 adults were randomized to onabotulinumtoxinA (n = 688) or placebo (n = 696). Pooled analyses demonstrated a large mean decrease from baseline in frequency of headache days, with statistically significant between-group differences favoring onabotulinumtoxinA over placebo at week 24 (-8.4 vs -6.6; P < .001) and at all other time points. Significant differences favoring onabotulinumtoxinA were also observed for all secondary efficacy variables at all time points, with the exception of frequency of acute headache pain medication intakes. Adverse events occurred in 62.4% of onabotulinumtoxinA patients and 51.7% of placebo patients. Most patients reported adverse events that were mild to moderate in severity and few discontinued (onabotulinumtoxinA, 3.8%; placebo, 1.2%) due to adverse events. No unexpected treatment-related adverse events were identified.

CONCLUSIONS

The pooled PREEMPT results demonstrate that onabotulinumtoxinA is an effective prophylactic treatment for chronic migraine. OnabotulinumtoxinA resulted in significant improvements compared with placebo in multiple headache symptom measures, and significantly reduced headache-related disability and improved functioning, vitality, and overall health-related quality of life. Repeat treatments with onabotulinumtoxinA were safe and well tolerated.

OnabotulinumtoxinA for treatment of chronic migraine: results from the double-blind, randomized, placebo-controlled phase of the PREEMPT 1 trial

OBJECTIVES

This is the first of a pair of studies designed to assess efficacy, safety and tolerability of onabotulinumtoxinA (BOTOX) as headache prophylaxis in adults with chronic migraine.

METHODS

The Phase III REsearch Evaluating Migraine Prophylaxis Therapy 1 (PREEMPT 1) is a phase 3 study, with a 24-week, double-blind, parallel-group, placebo-controlled phase followed by a 32-week, open-label phase. Subjects were randomized (1:1) to injections every 12 weeks of onabotulinumtoxinA (155 U-195 U; n = 341) or placebo (n = 338) (two cycles). The primary endpoint was mean change from baseline in headache episode frequency at week 24.

RESULTS

No significant between-group difference for onabotulinumtoxinA versus placebo was observed for the primary endpoint, headache episodes (-5.2 vs. -5.3; p = 0.344). Large within-group decreases from baseline were observed for all efficacy variables. Significant between-group differences for onabotulinumtoxinA were observed for the secondary endpoints, headache days (p = .006) and migraine days (p = 0.002). OnabotulinumtoxinA was safe and well tolerated, with few treatment-related adverse events. Few subjects discontinued due to adverse events.

CONCLUSIONS

There was no between-group difference for the primary endpoint, headache episodes. However, significant reductions from baseline were observed for onabotulinumtoxinA for headache and migraine days, cumulative hours of headache on headache days and frequency of moderate/severe headache days, which in turn reduced the burden of illness in adults with disabling chronic migraine.

OnabotulinumtoxinA for treatment of chronic migraine: results from the double-blind, randomized, placebo-controlled phase of the PREEMPT 2 trial

OBJECTIVES

This is the second of a pair of studies designed to evaluate the efficacy and safety of onabotulinumtoxinA (BOTOX) for prophylaxis of headaches in adults with chronic migraine.

METHODS

PREEMPT 2 was a phase 3 study, with a 24-week, double-blind, placebo-controlled phase, followed by a 32-week, open-label phase. Subjects were randomized (1:1) to injections of onabotulinumtoxinA (155U-195U; n = 347) or placebo (n = 358) every 12 weeks for two cycles. The primary efficacy endpoint was mean change in headache days per 28 days from baseline to weeks 21-24 post-treatment.

RESULTS

OnabotulinumtoxinA was statistically significantly superior to placebo for the primary endpoint, frequency of headache days per 28 days relative to baseline (-9.0 onabotulinumtoxinA/-6.7 placebo, p < .001). OnabotulinumtoxinA was significantly favoured in all secondary endpoint comparisons. OnabotulinumtoxinA was safe and well tolerated, with few treatment-related adverse events. Few patients (3.5% onabotulinumtoxinA/1.4% placebo) discontinued due to adverse events.

CONCLUSIONS

The results of PREEMPT 2 demonstrate that onabotulinumtoxinA is effective for prophylaxis of headache in adults with chronic migraine. Repeated onabotulinumtoxinA treatments were safe and well tolerated.

Epidemiology, risk factors, and treatment of chronic migraine: a focus on topiramate

The term chronic daily headache refers to a heterogeneous group of headache disorders characterized by a frequency of headaches on > or = 15 days per month. Chronic migraine is a subtype of chronic daily headache. The prevalence of chronic migraine is approximately 1%. Baseline attack frequency and acute medication overuse have been identified as potential risk factors for the progression of migraine from an episodic disorder to a chronic condition. There is an unmet patient need for effective and safe treatments for patients with chronic migraine, but data from rigorous controlled trials are limited. Previous studies have demonstrated that topiramate is an effective and safe preventive treatment for episodic migraine. In addition, pilot studies have suggested the utility of topiramate for the prevention of chronic migraine. Two randomized, double-blind, placebo-controlled, multicenter trials investigating the efficacy and safety of topiramate in the treatment of patients with chronic migraine have recently been completed. This review presents comparative data from these 2 clinical trials, which suggest that topiramate at a dose of 100 mg daily is effective and generally well tolerated in chronic migraine.

Utility of Topiramate for the Treatment of Patients with Chronic Migraine in the Presence or Absence of Acute Medication Overuse

Chronic migraine has been linked to the excessive use of acute headache medications. Medication overuse (MO) is commonly considered the most significant risk factor for the progression of migraine from an episodic to a chronic condition. Managing MO is a challenge. Discontinuation of the acute medication can result in withdrawal headache, nausea, vomiting and sleep disturbances. This review summarizes the results from two similarly designed, randomized, placebo- controlled, multicentre studies of chronic migraine conducted in the USA and European Union. Both studies demonstrate the efficacy and safety of the migraine preventive medication, topiramate, for the treatment of chronic migraine in patient populations both with and without MO. These studies may have important implications for the future of chronic migraine management, suggesting that detoxification prior to initiating prophylactic therapy may not be required in all patients if MO is present.

Chronic migraine and medication overuse headache: clarifying the current International Headache Society classification criteria

Despite the recent advances in the understanding and classification of the chronic daily headaches, considerable controversy still exists regarding the classification of individual headaches, including chronic migraine (CM) and medication overuse headache (MOH). The original criteria, published in 2004, were difficult to apply to most patients with these disorders and were subsequently revised, resulting in broader clinical applicability. Nonetheless, they remain a topic of debate, and the revisions to the criteria have further added to the confusion. Even some prominent headache specialists are unsure which criteria to use. We aimed to explain the nature of the controversies surrounding the entities of CM and MOH. A clinical case will be used to illustrate some of the problems faced by clinicians in diagnosing patients with chronic daily headache.

The face of chronic migraine: epidemiology, demographics, and treatment strategies

Chronic daily headache (CDH) represents a therapeutic challenge for many clinicians. Treatment strategies should be aimed at correctly identifying the presence of CDH. In addition, an effective prophylactic regimen should be initiated; the presence of medication overuse must be addressed, and the offending medication being overused must be discontinued. Aside from analgesic overuse, other modifiable risk factors associated with the development of chronic migraine and CDH must be addressed including obesity and caffeine use and the effective management of comorbid conditions such as depression, anxiety, and sleep-related breathing disorders.

Is Chronic Migraine One End of a Spectrum of Migraine or a Separate Entity?

Chronic migraine is associated with abnormalities in the periaqueductal grey that may be progressive. The condition is also associated with a greater degree of impairment in cortical processing of sensory stimuli than episodic migraine, perhaps due to more pervasive or persistent cortical hyperexcitability These findings fit with the model of migraine as a spectrum disorder, in which the clinical and pathophysiological features may progress over time. This progression may result from changes in nociceptive thresholds and ensuing central sensitization caused by recurrent migraine in susceptible individuals. This may lead to changes in baseline neurological function between headaches, evident not only in electrophysiological and functional imaging studies, but also as psychological and somatic complaints that occur after years of episodic migraine. From current research and migraine models, a conceptualization of chronic migraine is emerging in which relatively permanent and pervasive central changes have occurred that warrant novel and tolerable treatments.

The evolution of chronic migraine: classification and nomenclature

After nearly 3 decades of debate, the headache community still lacks globally accepted criteria for chronic migraine. This review summarizes the evolution of chronic migraine nomenclature and criteria. We concluded that although there are discrepancies in the currently proposed criteria, there is a significant amount of overlap with previously used classifications such that they all appear to describe the same subset of highly burdened migraine patients. In order to continue to understand the natural history of chronic migraine, address the unmet medical need, and develop effective therapies, field experts and physicians must have a classification that is well understood and accepted by the broader clinical community. It is our view that of the currently established classifications, the Silberstein and Lipton revised criteria for transformed migraine are the most applicable to daily clinical practice and field research.

Medication Overuse Headache and Chronic Migraine in a Specialized Headache Centre: Field-Testing Proposed New Appendix Criteria

The classification subcommittee of the International Headache Society (IHS) has recently suggested revised criteria for medication overuse headache (MOH) and chronic migraine (CM). We field tested these revised criteria by applying them to the headache population at the Danish Headache Centre and compared the results with those using the current criteria. For CM we also tested two alternative criteria, one requiring ≥ 4 migraine days/month and ≥ 15 headache days/month, the second requiring ≥ 15 headache days/month and ≥ 50% migraine days. We included 969 patients with migraine or tension-type headache (TTH) among 1326 patients treated and dismissed in a 2-year period. Two hundred and eighty-five patients (30%) had TTH, 265 (27%) had migraine and 419 (43%) had mixed migraine and TTH. The current criteria for MOH classified 86 patients (9%) as MOH, 98 (10%) as probable MOH and 785 (81%) as not having MOH after a 2-month drug-free period. Using the appendix criteria, 284 patients (29%) were now classified as MOH, no patients as probable MOH and 685 (71%) as not having MOH. For CM only 16 patients (3%) fulfilled the current diagnostic criteria. This increased to 42 patients (7%) when we applied the appendix criteria. Using the less restrictive criteria of ≥ 4 migraine days and ≥ 15 headache days, 88 patients (14%) had CM, whereas the more restrictive criteria of ≥ 15 headache days and ≥ 50% migraine days resulted in 24 patients (4%) with CM. Our data suggest that the IHS has succeeded in choosing new criteria for CM which are neither too strict, nor too loose. For MOH, a shift to the appendix criteria will increase the number of MOH patients, but take into account the possibility of permanent changes in pain perception due to medication overuse and the possibility of a renewed effect of prophylactic drugs due to medication withdrawal. We therefore recommend the implementation of the appendix criteria for both MOH and CM into the main body of the International Classification of Headache Disorders.

[Management of chronic daily headache in children and adolescents]

Chronic daily headache (CDH) affects 2 to 4% of adolescent females and 0,8 to 2% of adolescent males. CDH is diagnosed when headaches occur more than 4 hours a day, for greater than or equal to 15 headache days per month, over a period of 3 consecutive months, without an underlying pathology. It is manifested by severe intermittent headaches, that are migraine-like, as well as a chronic baseline headache. Silberstein and Lipton divided patients into four diagnostic categories: transformed migraine, chronic tension-type headache, new daily-persistent headache, and hemicrania continua. The second edition of the International Classification of Headache Disorders did not comprise any CDH category as such, but provided criteria for all four types of CDH: chronic migraine, chronic tension-type headache, new daily-persistent headache, and hemicrania continua. Evaluation of CDH needs to include a complete history and physical examination to identify any possibility of the headache representing secondary headaches. Children and adolescents with CDH frequently have sleep disturbance, pain at other sites, dizziness, medication-overuse headache and a psychiatric comorbidity (anxiety and mood disorders). CDH frequently results in school absence. CDH management plan is dictated by CDH subtype, the presence or absence of medication overuse, functional disability and presence of attacks of full-migraine superimposed. Reassuring, explaining, and educating the patient and family, starting prophylactic therapy and limiting aborting medications are the mainstay of treatment. It includes pharmacologic (acute and prophylactic therapy) and nonpharmacologic measures (biobehavioral management, biofeedback-assisted relaxation therapy, and psychologic or psychiatric intervention). Part of the teaching process must incorporate life-style changes, such as regulation of sleep and eating habits, regular exercise, avoidance of identified triggering factors and stress management. Emphasis must be placed on preventive measures rather than on analgesic or abortive strategies. Stressing the reintegration of the patient into school and family activities and assessing prognosis are other issues to address during the first visit. There are limited data evaluating the outcome of CDH in children and adolescents.

When should "chronic migraine" patients be considered "refractory" to pharmacological prophylaxis?

Patients with chronic headache forms evolving from a previous episodic migraine ('chronic migraine') are often difficult to treat. In this paper we focus attention on aspects we believe important for producing a definition of "refractory" in relation to this headache form. We propose a "chronic migraine" patient should be considered "refractory" to pharmacological prophylaxis when adequate trials of preventive therapies at adequate doses have failed to reduce headache frequency and improve headache-related disability and, in patients with medication overuse, reduce the consumption of symptomatic drugs. However before a definition of "refractory" chronic migraine can become established, generally accepted diagnostic criteria and treatment guidelines for this condition need to be developed.

The classification of chronic daily headache in French children and adolescents: a comparison between the second edition of the International Classification of Headache Disorders and Silberstein-Lipton criteria

Few data are available on the applicability of both the criteria proposed by Silberstein and Lipton (S-L) and the International Classification of Headache Disorders-II (ICHD-II) in the classification of children and adolescents with chronic daily headache (CDH). The International Headache Society recently added revised criteria (ICHD-IIR) for chronic migraine to its Appendix. We retrospectively reviewed all charts of 34 children and adolescents (<17 years) with primary CDH presenting to the outpatient clinic of the Universitary Department of Neuropediatrics of Lille between February 2004 and February 2006 and tried to classify their CDH according to both S-L criteria and the recently published ICHD-IIR. Thirty-two children (94%) and 33 children (97%) could respectively be successfully classified into one subtype of CDH according to the S-L classification and the ICHD-IIR. Transformed migraine was the most common diagnosis (61.8%), followed by new daily-persistent headache (20.6%) when the S-L criteria were used. Twenty-three children and adolescents (67.6%) could be classified under one of the migraine categories according to the ICHD-IIR classification. We think that both S-L and ICHD-II classifications, when used with detailed headache histories and diaries, are adequate to classify chronic daily headache in children and adolescents.

The differential diagnosis of chronic daily headaches: an algorithm-based approach

Chronic daily headaches (CDHs) refers to primary headaches that happen on at least 15 days per month, for 4 or more hours per day, for at least three consecutive months. The differential diagnosis of CDHs is challenging and should proceed in an orderly fashion. The approach begins with a search for "red flags" that suggest the possibility of a secondary headache. If secondary headaches that mimic CDHs are excluded, either on clinical grounds or through investigation, the next step is to classify the headaches based on the duration of attacks. If the attacks last less than 4 hours per day, a trigeminal autonomic cephalalgia (TAC) is likely. TACs include episodic and chronic cluster headache, episodic and chronic paroxysmal hemicrania, SUNCT, and hypnic headache. If the duration is > or =4 h, a CDH is likely and the differential diagnosis encompasses chronic migraine, chronic tension-type headache, new daily persistent headache and hemicrania continua. The clinical approach to diagnosing CDH is the scope of this review.

Efficacy and safety of topiramate for the treatment of chronic migraine: a randomized, double-blind, placebo-controlled trial

OBJECTIVE

To evaluate the efficacy and safety of topiramate (100 mg/day) compared with placebo for the treatment of chronic migraine.

METHODS

This was a randomized, placebo-controlled, parallel-group, multicenter study consisting of 16 weeks of double-blind treatment. Subjects aged 18 to 65 years with 15 or more headache days per month, at least half of which were migraine/migrainous headaches, were randomized 1:1 to either topiramate 100 mg/day or placebo. An initial dose of topiramate 25 mg/day (or placebo) was titrated upward in weekly increments of 25 mg/day to a maximum of 100 mg/day (or to the maximum tolerated dose). Concomitant preventive migraine treatment was not allowed, and acute headache medication use was not to exceed 4 days per week during the double-blind maintenance period. The primary efficacy endpoint was the change from baseline in the mean monthly number of migraine/migrainous days; the change in the mean monthly number of migraine days also was analyzed. A fixed sequence approach (ie, gatekeeper approach) using analysis of covariance was used to analyze the efficacy endpoints. Assessments of safety and tolerability included physical and neurologic examinations, clinical laboratory parameters, and spontaneous reports of clinical adverse events.

RESULTS

The intent-to-treat population included 306 (topiramate, n = 153; placebo, n = 153) of 328 randomized subjects who provided at least 1 efficacy assessment; 55.8% of the topiramate group and 55.2% on placebo were trial completers. The mean final topiramate maintenance dose was 86.0 mg/day. The mean duration of therapy was 91.7 days for the topiramate group and 90.6 days for the placebo group. Topiramate treatment resulted in a statistically significant mean reduction of migraine/migrainous headache days (topiramate -6.4 vs placebo -4.7, P= .010) and migraine headache days relative to baseline (topiramate -5.6 vs placebo -4.1, P= .032). Treatment-emergent adverse events occurred in 132 (82.5%) and 113 (70.2%) of topiramate-treated and placebo-treated subjects, respectively, and were generally of mild or moderate severity. Most commonly reported adverse events in the topiramate group were paresthesia (n = 46, 28.8%), upper respiratory tract infection (n = 22, 13.8%), and fatigue (n = 19, 11.9%). The most common adverse events in the placebo group were upper respiratory tract infection (n = 20, 12.4%), fatigue (n = 16, 9.9%), and nausea (n = 13, 8.1%). Discontinuations due to adverse events occurred in 18 (10.9%) topiramate subjects and 10 (6.1%) placebo subjects. There were no serious adverse events or deaths.

CONCLUSIONS

Topiramate treatment at daily doses of approximately 100 mg resulted in statistically significant improvements compared with placebo in mean monthly migraine/migrainous and migraine headache days. Topiramate is safe and generally well tolerated in this group of subjects with chronic migraine, a burdensome condition with important unmet treatment needs. Safety and tolerability of topiramate were consistent with experience in previous clinical trials involving the drug.

Chronic daily headaches in children

Chronic daily headache (CDH) is increasingly recognized as a problem in pediatrics and tertiary pediatric headache care. It is estimated that up to 4% of the adult population has CDH. Many of these are chronic migraine (CM). The fraction of the pediatric population with CDH appears to be lower, although the prevalence has not been adequately determined. The simplest definition of CDH is more than 15 headache days per month. In the International Classification of Headache Disorders, Second Edition (ICHD-II), several types of CDH have been identified. These criteria have been contrasted with the Silberstein-Lipton criteria, with revisions suggested. The diagnosis of CDH is further complicated and may be initiated by the overuse of analgesic medications (medication overuse headache) and requires the resolution of this issue before a final diagnosis can be established. In children, most CDH appears to have migraine features, although it may not completely meet the ICHD-II criteria for migraine or CM. Evaluation of CDH needs to include a complete history and physical examination to identify any possibility of the secondary headaches or headaches directly attributed to a secondary cause. Treatment and management involve a multidisciplinary approach, including acute therapy for when the headache severity increases (while avoiding medication overuse), preventative therapy to reduce the frequency and impact of the CDH, and biobehavioral therapy to assist with long-term outcome.

Botulinum toxin type A for the treatment of migraine

Migraine is a common and debilitating disorder that often requires prophylactic therapy, particularly for those migraine patients who meet the diagnostic criteria for chronic daily headache (chronic migraine). Existing prophylactic treatments for migraine are inadequate for many patients due to their modest efficacy and/or systemic side effects. Alternative treatment strategies are needed, particularly in those with chronic migraine. Botulinum toxin type A is a locally injected protein complex that has been investigated as a treatment for episodic migraine and chronic daily headache. A systematic series of controlled trials has led to the identification of a subset of migraineurs with chronic daily headache who obtain demonstrated benefits of botulinum toxin type A over placebo that is maintained with repeated treatments.