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

Nonpharmacologic Treatments for Chronic and Episodic Migraine: A Systematic Review and Meta-Analysis

BACKGROUND

Minimally invasive techniques for treatment-resistant migraine have been developed on recent insights into the peripheral pathogenesis of migraines. Although there is a growing body of evidence supporting these techniques, no study has yet compared the effects of these treatments on headache frequency, severity, duration, and cost.

METHODS

PubMed, Embase, and Cochrane Library databases were searched to identify randomized placebo-controlled trials that compared radiofrequency ablation, botulinum toxin type A (BT-A), nerve block, neurostimulation, or migraine surgery to placebo for preventive treatment. Data on changes from baseline to follow-up in headache frequency, severity, duration, and quality of life were analyzed.

RESULTS

A total of 30 randomized controlled trials and 2680 patients were included. Compared with placebo, there was a significant decrease in headache frequency in patients with nerve block ( P = 0.04) and surgery ( P < 0.001). Headache severity decreased in all treatments. Duration of headaches was significantly reduced in the BT-A ( P < 0.001) and surgery cohorts ( P = 0.01). Quality of life improved significantly in patients with BT-A, nerve stimulator, and migraine surgery. Migraine surgery had the longest lasting effects (11.5 months) compared with nerve ablation (6 months), BT-A (3.2 months), and nerve block (11.9 days).

CONCLUSIONS

Migraine surgery is a cost-effective, long-term treatment to reduce headache frequency, severity, and duration without significant risk of complication. BT-A reduces headache severity and duration, but it is short-lasting and associated with greater adverse events and lifetime cost. Although efficacious, radiofrequency ablation and implanted nerve stimulators have high risks of adverse events and explantation, whereas benefits of nerve blocks are short in duration.

Breaking the cycle: unraveling the diagnostic, pathophysiological and treatment challenges of refractory migraine

Background

Refractory migraine is a poorly described complication of migraine in which migraine has chronified and become resistant to standard treatments. The true prevalence is unknown, but medication resistance is common in headache clinic patient populations. Given the lack of response to treatment, this patient population is extremely difficult to treat with limited guidance in the literature.

Objective

To review the diagnostic, pathophysiological, and management challenges in the refractory migraine population.

Discussion

There are no accepted, or even ICHD-3 appendix, diagnostic criteria for refractory migraine though several proposed criteria exist. Current proposed criteria often have low bars for refractoriness while also not meeting the needs of pediatrics, lower socioeconomic status, and developing nations. Pathophysiology is unknown but can be hypothesized as a persistent "on" state as a progression from chronic migraine with increasing central sensitization, but there may be heterogeneity in the underlying pathophysiology. No guidelines exist for treatment of refractory migraine; once all guideline-based treatments are tried, treatment consists of n-of-1 treatment trials paired with non-pharmacologic management.

Conclusion

Refractory migraine is poorly described diagnostically, its pathophysiology can only be guessed at by extension of chronic migraine, and treatment is more the art than science of medicine. Navigating care of this refractory population will require multidisciplinary care models and an emphasis on future research to answer these unknowns.

Refractory Headaches

Medication overuse headache (MOH), new daily persistent headache (NDPH), and persistent refractory headache attributed to severe acute respiratory syndrome coronavirus 2 (SARS-CoV2) infection represent a significant burden in terms of disability and quality of life, and a challenge in terms of definition, pathophysiology, and treatment. Regarding MOH, prevention without withdrawal is not inferior to prevention with withdrawal. Preventive medications like topiramate, onabotulinumtoxinA, and calcitonin gene-related peptide (CGRP) monoclonal antibodies improve chronic migraine with MOH regardless of withdrawal. The differential diagnosis of NDPH is broad and should be carefully examined. There are no guidelines for the treatment of NDPH, but options include a short course of steroids, nerve blocks, topiramate, nortriptyline, gabapentin, CGRP monoclonal antibodies, and onabotulinumtoxinA. The persistence of headache 3 months after SARS-CoV2 infection is a predictor of poor prognosis.

Real-life assessment of erenumab in refractory chronic migraine with medication overuse headache

OBJECTIVE

To determine whether erenumab is effective and safe in refractory chronic migraine with medication overuse headache.

METHODS

In this prospective, multicentric, real-life study, chronic migraine with medication overuse headache patients who received erenumab were recruited. Study inclusion was limited to patients who previously failed onabotulinumtoxinA in addition to at least three other pharmacological commonly used migraine preventive medication classes.

RESULTS

Of 396 patients who received erenumab, 38% (n = 149) met inclusion criteria. After 3 months, 51% (n = 76) and 20% (n = 30) patients achieved ≥ 50% and ≥ 75% reduction in monthly headache days, respectively. Monthly pain medications intake decreased from 46.1 ± 35.3 to 16.8 ± 13.9 (p < 0.001), while monthly headache days decreased from 25.4 ± 5.4 to 14.1 ± 8.6 (p < 0.001). Increasing efficacy of erenumab over the study period was observed. Allodynia was a negative predictive factor of erenumab response (odds ratio = 0.47; p = 0.03). Clinical conversion to episodic migraine with no medication overuse was observed in 64% (n = 96) patients. No serious adverse events were observed.

CONCLUSIONS

Erenumab reduced significantly migraine frequency and pain medication intake in refractory chronic migraine with MOH patients.

Severe migraine and its control: A proposal for definitions and consequences for care

Currently many patients with severe migraine do not receive appropriate treatment and are never referred to specialist headache centres. On the other hand, specialist headache centres are frequently attended by patients whose migraines could be managed adequately in the community. One reason for this may be the absence of standardised definitions of migraine severity and control and of a treatment algorithm for orientating difficult-to-treat patients to specialist headache centres. Based on a review of the relevant literature and consensus meetings, proposals have been made for these items. We propose that migraine should be considered severe if headache frequency is at least eight migraine days per month or, if headaches are less frequent, the HIT-6 score is ≥60 or ≥50% of headaches require complete interruption of activity. The proposed definition of migraine control is defined on the basis of appropriate response to acute headache therapy and to preventative therapy. A treatment algorithm is proposed to assess migraine control regularly and to adapt therapy accordingly. These proposals may contribute to developing and testing strategies for management of severe disease with appropriate and effective preventive treatment strategies. With the anticipated introduction of new possibilities for migraine prevention in the near future, the time is ripe for a holistic approach to migraine management.

Decompression Surgery for Frontal Migraine Headache

INTRODUCTION

Migraine headache (MH) is one of the most common diseases worldwide and pharmaceutical treatment is considered the gold standard. Nevertheless, one-third of patients suffering from migraine headaches are unresponsive to medical management and meet the criteria for "refractory migraines" classification. Surgical treatment of MH might represent a supplementary alternative for this category of patients when pharmaceutical treatment does not allow for satisfactory results. The goal of this article is to provide a comprehensive review of the literature regarding surgical treatment for site I migraine management.

METHODS

A literature search using PubMed, Medline, Cochrane and Google Scholar database according to Preferred Reporting Items for Systematic Reviews and Meta-Analysis guidelines was conducted using the following MeSH terms: "frontal neuralgia," "frontal trigger site treatment," "frontal migraine surgery" and "frontal headache surgery" (period: 2000 -2020; last search on 12 March 2020).

RESULTS

Eighteen studies published between 2000 and 2019, with a total of 628 patients, were considered eligible. Between 68% and 93% of patients obtained satisfactory postoperative results. Complete migraine elimination rate ranged from 28.3% to 59%, and significant improvement (>50% reduction) rates varied from 26.5% to 60%.

CONCLUSIONS

Our systematic review of the literature suggests that frontal trigger site nerve decompression could possibly be an effective strategy to treat migraine refractory patients, providing significant improvement of symptoms in a considerable percentage of patients.

European headache federation consensus on the definition of resistant and refractory migraine : Developed with the endorsement of the European Migraine & Headache Alliance (EMHA)

INTRODUCTION

Despite advances in the management of headache disorders, some patients with migraine do not experience adequate pain relief with acute and preventive treatments. It is the aim of the present document to provide a definition of those migraines which are difficult-to-treat, to create awareness of existence of this group of patients, to help Healthcare Authorities in understanding the implications, and to create a basis to develop a better pathophysiological understanding and to support further therapeutic advances.

MAIN BODY

Definitions were established with a consensus process using the Delphi method. Patients with migraine with or without aura or with chronic migraine can be defined as having resistant migraine and refractory migraine according to previous preventative failures. Resistant migraine is defined by having failed at least 3 classes of migraine preventatives and suffer from at least 8 debilitating headache days per month for at least 3 consecutive months without improvement; definition can be based on review of medical charts. Refractory migraine is defined by having failed all of the available preventatives and suffer from at least 8 debilitating headache days per month for at least 6 consecutive months. Drug failure may include lack of efficacy or lack of tolerability. Debilitating headache is defined as headache causing serious impairment to conduct activities of daily living despite the use of pain-relief drugs with established efficacy at the recommended dose and taken early during the attack; failure of at least two different triptans is required.

CONCLUSIONS

We hope, that the updated EHF definition will be able to solve the conflicts that have limited the use of definitions which have been put forward in the past. Only with a widely accepted definition, progresses in difficult-to-treat migraine can be achieved. This new definition has also the aim to increase the understanding of the impact of the migraine as a disease with all of its social, legal and healthcare implications. It is the hope of the EHF Expert Consensus Group that the proposed criteria will stimulate further clinical, scientific and social attention to patients who suffer from migraine which is difficult-to-treat.

Population-Based Health Utility Assessment of Migraine Headache Symptoms before and after Surgical Intervention

BACKGROUND

Approximately 30 million Americans suffer from migraine headaches. The primary goals of this study are to (1) use Migraine-Specific Symptoms and Disability criteria and Migraine Headache Index to describe the symptomatic improvement following decompressive surgery for refractory migraines, and (2) use the average Migraine Headache Index preoperatively and postoperatively for health utility assessment from a healthy patient's perspective.

METHODS

The Migraine-Specific Symptoms and Disability criteria and the Migraine Headache Index were used to characterize migraine symptoms in the authors' patient population before and after decompressive surgery. Healthy individuals were randomized to a scenario in which they assumed either the preoperative or postoperative average patient symptom profile described by the authors' migraine patients. Health utility assessments were used to quantify the evaluation of health states the authors' patients experienced before and after surgical migraine therapy.

RESULTS

Twenty-five patients underwent surgery for migraine headaches. The Migraine-Specific Symptoms and Disability questionnaire showed a significant decrease in both frequency of headaches per month (p < 0.0001) and overall pain score (p = 0.007). The Migraine Headache Index demonstrated a statistically significant improvement (p = 0.03). Healthy individuals in the preoperative group had significantly lower utility scores compared with the postoperative group in all of the health utility assessments completed for migraine symptoms.

CONCLUSION

This is the first study to use health utility assessments to attest the efficacy of decompressive therapy by demonstrating the population perspective, which perceived a significant improvement in quality of life following the surgical treatment of migraines in the authors' patients.

CLINICAL QUESTION/LEVEL OF EVIDENCE

Therapeutic, IV.

Surgical intervention for chronic migraine headache: A systematic review

•

A focus on sound systematic review methodology to present an unbiased and scientific assessment of the body of knowledge for migraine surgery.

•

Comprehensive search strategy included a range of study types to capture all relevant reports of primary clinical research, enabling a global evaluation of the topic.

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A descriptive analysis allowing an overview of the likely effect of a variety of surgical interventions, with a snapshot of the rates of recurrence and adverse events.

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Formalised assessment of methodological quality using the GRADE approach identifies specific flaws affecting the reliability of migraine surgery research to date.

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Limited by a paucity of methodological quality in included studies, heterogeneous interventions, inconsistent outcome reporting and variability in baseline data, intervention data and outcome data.

Aims

Migraine is a global phenomenon, affecting more than 10% of the world's population. It is characterized by unilateral headache that may be accompanied by vomiting, nausea, photophobia and phonophobia. Some patients with chronic migraine respond to extra-cranial botulinum toxin type A injection, although the benefits observed are temporary. The rationale for surgical trigger site deactivation is to achieve lasting symptomatic improvement or permanent relief from migraine.

Methods

We performed a PRISMA-compliant systematic review of clinical studies evaluating surgical intervention for migraine by searching Ovid MEDLINE and EMBASE databases from inception to June 2017. Studies were independently screened by two authors. Data were extracted on study characteristics, migraine outcomes, adverse events and recurrence. The quality of evidence was assessed using the GRADE approach. The review protocol was prospectively registered on the PROSPERO database (CRD42017068577).

Results

The search strategy identified 789 articles; of them, 18 studies (4 RCTs and 14 case series) were eligible for analysis. Surgical interventions were heterogeneous and variably involved peripheral nerve decompression by myectomy or foraminotomy, nerve excision, artery resection and/or nasal surgery. All studies reported significant reductions in migraine intensity, frequency, duration and composite headache scores following surgery. Study heterogeneity precluded formal meta-analysis. Where reported, adverse event rates varied markedly between studies. The quality of included studies was consistently low or very low.

Conclusion

There is insufficient evidence to support the effectiveness of any specific surgical intervention for chronic migraine, especially with regard to permanent relief; however, all included studies report improvements in key outcomes following migraine surgery. A definitive, well-powered RCT with objective surgical and patient-reported outcome measures and robust adverse event reporting is required.

A comparison of outcome of medical and surgical treatment of migraine headache: In 1 year follow-up

BACKGROUND

This study was designed to compare the efficacy of the medical treatment versus the surgical treatment approach to decompression of trigger point nerves in patients with migraine headaches.

MATERIALS AND METHODS

Fifty volunteers were randomly assigned to the medical treatment group (n = 25) or the surgical treatment group (n = 25) after examination by the team neurologist to ensure a diagnosis of migraine headache. All patients received botulinum toxin type A to confirm the trigger sites. The surgical treatment group underwent surgical deactivation of the trigger site(s). The medical treatment group underwent prophylactic pharmacologic interventions by the neurologist. Pretreatment and 12-month posttreatment migraine headache frequency, duration, and intensity were analyzed and compared to determine the success of the treatments.

RESULTS

Nineteen of the 25 patients (76%) in the surgical treatment group and 10 of the 25 patients (40%) in the medical treatment group experienced a successful outcome (at least a 50% decrease in migraine frequency, duration, or intensity) after 1 year from surgery. Surgical treatment had a significantly higher success rate than medical treatment (P < 0.001). Nine patients (36%) in the surgical treatment group and one patient (4%) in the medical treatment group experienced cessation of migraine headaches. The elimination rate was significantly higher in the surgical treatment group than in the medical treatment group (P < 0.001).

CONCLUSIONS

Based on the 1-year follow-up data, there is strong evidence that surgical manipulation of one or more migraine trigger sites can successfully eliminate or reduce the frequency, duration, and intensity of migraine headaches in a lasting manner.

Refractory chronic migraine: a consensus statement on clinical definition from the European Headache Federation

The debate on the clinical definition of refractory Chronic Migraine (rCM) is still far to be concluded. The importance to create a clinical framing of these rCM patients resides in the complete disability they show, in the high risk of serious adverse events from acute and preventative drugs and in the uncontrolled application of therapeutic techniques not yet validated.

The European Headache Federation Expert Group on rCM presents hereby the updated definition criteria for this harmful subset of headache disorders. This attempt wants to be the first impulse towards the correct identification of these patients, the correct application of innovative therapeutic techniques and lastly aim to be acknowledged as clinical entity in the next definitive version of the International Classification of Headache Disorders 3 (ICHD-3 beta).

Refractory migraine: the role of the physician in assessment and treatment of a problematic disease

Patients affected by chronic forms of headache are often very difficult to treat. Refractory patients are so defined when adequate trials of specific drugs (for acute or prophylactic treatment) failed both to reduce the burden of disease and to improve headache-related quality of life. An escalating approach is suggested to test different kinds of therapies. All comorbid factors should be addressed. More invasive modalities (such as neurostimulation) or promising approaches such as repetitive transcranial magnetic stimulation (rTMS) could be a future major step as third line therapies.

Peripheral neuromodulation in chronic migraine

Patients with chronic migraines are often refractory to medical treatment. Therefore, they might need other strategies to modulate their pain, according to their level of disability. Neuromodulation can be achieved with several tools: meditation, biofeedback, physical therapy, drugs and electric neurostimulation (ENS). ENS can be applied to the central nervous system (brain and spinal cord), either invasively (cortical or deep brain) or non-invasively [cranial electrotherapy stimulation, transcranial direct current stimulation and transcranial magnetic stimulation]. Among chronic primary headaches, cluster headaches are most often treated either through deep brain stimulation or occipital nerve stimulation because there is a high level of disability related to this condition. ENS, employed through several modalities such as transcutaneous electrical nerve stimulation, interferential currents and pulsed radiofrequency, has been applied to the peripheral nervous system at several sites. We briefly review the indications for the use of peripheral ENS at the site of the occipital nerves for the treatment of chronic migraine.

Clinical outcomes following supraorbital foraminotomy for treatment of frontal migraine headache

BACKGROUND

Although 92 percent of patients who undergo surgical decompression of the supraorbital nerve for treatment of frontal migraine headaches through resection of the glabellar muscle group achieve at least 50 percent improvement, only two-thirds demonstrate complete resolution of symptoms. The authors investigated the role of additional decompression methods by comparing surgery outcomes between patients who underwent glabellar myectomy alone and patients who also underwent supraorbital foraminotomy.

METHODS

Outcome measures including migraine headache frequency, severity, and duration; Migraine Headache Index score; and forehead pain were reviewed retrospectively and analyzed statistically for 43 age-matched control patients who underwent glabellar myectomy for release of the supraorbital nerve and 43 patients who underwent glabellar myectomy with supraorbital foraminotomy from 2002 to 2010.

RESULTS

The myectomy group statistically matched the myectomy with foraminotomy group for age, number of surgical sites, and preoperative headache characteristics (p > 0.05). For the myectomy and myectomy with foraminotomy groups, postoperative migraine frequency was 7.8 per month versus 4.1 per month, severity was 5.6 versus 4.4, Migraine Headache Index score was 26.5 versus 11.1, and persistent forehead pain was 48.8 percent versus 25.6 percent, respectively. These differences were all statistically significant (p < 0.05). Duration of headache was unchanged (p = 0.17).

CONCLUSIONS

The supraorbital foramen is a potential site of supraorbital nerve compression that can trigger frontal migraine headache. If it is present, the authors strongly recommend foraminotomy to ensure complete release of the supraorbital nerve to optimize outcomes. Their results also support consideration of release of any fibrous bands across the supraorbital notch.

CLINICAL QUESTION/LEVEL OF EVIDENCE

Therapeutic, III.

Refractory migraine in a headache clinic population

BACKGROUND

Many migraineurs who seek care in headache clinics are refractory to treatment, despite advances in headache therapies. Epidemiology is poorly characterized, because diagnostic criteria for refractory migraine were not available until recently. We aimed to determine the frequency of refractory migraine in patients attended in the Headache Unit in a tertiary care center, according to recently proposed criteria.

METHODS

The study population consisted of a consecutive sample of 370 patients (60.8% females) with a mean age of 43 years (range 14-86) evaluated for the first time in our headache unit over a one-year period (between October 2008 and October 2009). We recorded information on clinical features, previous treatments, Migraine Disability Assessment Score (MIDAS), and final diagnosis.

RESULTS

Overall migraine and tension-type headache were found in 46.4% and 20.5% of patients, respectively. Refractory migraine was found in 5.1% of patients. In refractory migraineurs, the mean MIDAS score was 96, and 36.8% were medication-overusers.

CONCLUSIONS

Refractory migraine is a relatively common and very disabling condition between the patients attended in a headache unit. The proposed operational criteria may be useful in identifying those patients who require care in headache units, the selection of candidates for combinations of prophylactic drugs or invasive treatments such as neurostimulation, but also to facilitate clinical studies in this patient group.

Migraine surgery: a plastic surgery solution for refractory migraine headache

Migraine headache can be a debilitating condition that confers a substantial burden to the affected individual and to society. Despite significant advancements in the medical management of this challenging disorder, clinical data have revealed a proportion of patients who do not adequately respond to pharmacologic intervention and remain symptomatic. Recent insights into the pathogenesis of migraine headache argue against a central vasogenic cause and substantiate a peripheral mechanism involving compressed craniofacial nerves that contribute to the generation of migraine headache. Botulinum toxin injection is a relatively new treatment approach with demonstrated efficacy and supports a peripheral mechanism. Patients who fail optimal medical management and experience amelioration of headache pain after injection at specific anatomical locations can be considered for subsequent surgery to decompress the entrapped peripheral nerves. Migraine surgery is an exciting prospect for appropriately selected patients suffering from migraine headache and will continue to be a burgeoning field that is replete with investigative opportunities.

Vagus nerve stimulation in drug-resistant daily chronic migraine with depression: preliminary data

Drug refractory chronic daily headache (CDH) is a highly disabling condition. CDH is usually regarded as the negative evolution of chronic migraine (CM) and is characterized by high prevalence of psychiatric disorders, especially mood disorders. Vagal nerve stimulation (VNS) is an established treatment option for selected patients with medically refractory epilepsy and depression. Neurobiological similarities suggest that VNS could be useful in the treatment of drug-refractory CM associated with depression. The aim of the study was to evaluate the efficacy of VNS in patients suffering from drug-refractory CM and depressive disorder. We selected four female patients, mean age 53 (range 43-65 years), suffering from daily headache and drug-refractory CM. Neurological examination and neuroradiological investigations were unremarkable. Exclusion criteria were psychosis, heart and lung diseases. The preliminary results in our small case series support a beneficial effect of chronic VNS on both drug-refractory CM and depression, and suggest this novel treatment as a valid alternative for this otherwise intractable and highly disabling condition.

Prophylaxis of migraine: general principles and patient acceptance

Migraine is a chronic neurological condition with episodic exacerbations. Migraine is highly prevalent, and associated with significant pain, disability, and diminished quality of life. Migraine management is an important health care issue. Migraine management includes avoidance of trigger factors, lifestyle modifications, non-pharmacological therapies, and medications. Pharmacological treatment is traditionally divided into acute or symptomatic treatment, and preventive treatment or prophylaxis. Many migraine patients can be treated using only acute treatment. Patients with severe and/or frequent migraines require long-term preventive therapy. Prophylaxis requires daily administration of anti-migraine compounds with potential adverse events or contraindications, and may also interfere with other concurrent conditions and treatments. These problems may induce patients to reject the idea of a preventive treatment, leading to poor patient adherence. This paper reviews the main factors influencing patient acceptance of anti-migraine prophylaxis, providing practical suggestions to enhance patient willingness to accept pharmacological anti-migraine preventive therapy. We also provide information about the main clinical characteristics of migraine, and their negative consequences. The circumstances warranting prophylaxis in migraine patients as well as the main characteristics of the compounds currently used in migraine prophylaxis will also be briefly discussed, focusing on those aspects which can enhance patient acceptance and adherence.