Refractory migraine - a review

Impact of duration of chronic migraine on long-term effectiveness of monoclonal antibodies targeting the calcitonin gene-related peptide pathway-A real-world study

OBJECTIVE

We assessed whether the effectiveness of monoclonal antibodies (mAbs) targeting the calcitonin gene-related peptide (CGRP) pathway changes according to the duration of chronic migraine (CM) over 12 months.

BACKGROUND

In most patients, CM is a progressive disease starting with episodic migraine. Longer CM duration might be associated with more difficult treatment, probably because the mechanisms underlying chronicization are strengthened. Therefore, early treatment of CM could lead to better outcomes compared with later treatment.

METHODS

This cohort study included individuals with CM treated with anti-CGRP mAbs in two tertiary headache centers from April 2019 to May 2023. The primary outcome included a change in monthly migraine days (MMDs) from baseline to the third trimester of treatment, 10-12 months. Secondary outcomes established whether response to anti-CGRP mAbs has a more rapid onset in individuals with shorter CM duration compared with longer duration; they included change in MMDs, monthly headache days (MHDs), and days and number of intakes of acute medication during each trimester compared to baseline. Additional outcomes included persisting MMDs, MHDs, and days and number of intakes of acute medication during each trimester of treatment. Patients were compared across tertiles of the overall CM duration.

RESULTS

The study included 335 individuals with CM, with a median (interquartile range [IQR]) age of 48 (39-57) years; 270 (80.6%) were women. Patients in the highest tertile of CM duration (aged 18-60 years) were older than patients in the lower duration tertiles (0-7 years and 8-18 years, respectively), with a median (IQR) age of 56 (48-64) years compared with 42 (31-50) years, and 48 (39-56)years, respectively (p = 0.025); however, this difference was likely due to a correlation between age and disease duration. The change in MMDs from baseline to the last trimester of treatment (10-12 months) was comparable across tertiles of CM duration (median [IQR] -12 [-18 to -5] days, -12 [-17 to -6] days, and -12 [-18 to -4] days; p = 0.946). No difference emerged in secondary outcomes, suggesting a similar time to onset of anti-CGRP mAbs effect across all tertiles of CM duration.

CONCLUSIONS

Our data showed that anti-CGRP mAbs are effective and have a rapid onset of action in CM regardless of disease duration.

One Patient, Three Providers: A Multidisciplinary Approach to Managing Common Neuropsychiatric Cases

BACKGROUND

Neuropsychiatric cases require a multidisciplinary approach for effective management. This paper presented case-based discussions on migraine, dementia, epilepsy, mood disorders, neuralgia, and psychosis from the perspectives of a family physician, neurologist, and psychiatrist. The goal was to highlight the importance of collaboration between healthcare providers in managing these complex cases.

METHODS

The paper was based on the proceedings of the Mediterranean Neuropsychiatry Symposium, where experts from family medicine, neurology, and psychiatry came together for comprehensive case-based discussions. The CARE framework (Case Report, Appraisal, Research, and Education) was developed to guide reporting and evaluation of case reports in clinical practice.

RESULTS

Six cases were presented and discussed, highlighting the importance of a multidisciplinary approach in managing neuropsychiatric cases. The cases included chronic migraine with medication overuse, memory dysfunction with language and behavioral problems, refractory epileptic seizures with subjective sensory symptoms, bipolar affective disorder with normal pressure hydrocephalus, postherpetic neuralgia in a case with bipolar affective disorder, and psychosis with recurrent attacks with the abuse of several substances.

CONCLUSION

A biopsychosocial multidisciplinary approach is essential for managing neuropsychiatric cases effectively on behalf of the patients and public health of the country. The CARE framework can guide the reporting and evaluation of case reports in clinical practice, ensuring that patients receive comprehensive and effective care. Healthcare providers should collaborate to provide the best possible care for patients with complex and multifaceted needs.

Once-daily oral atogepant for the long-term preventive treatment of migraine: Findings from a multicenter, randomized, open-label, phase 3 trial

OBJECTIVE

To assess long-term safety, tolerability, and efficacy of once-daily oral atogepant 60 mg in adults with migraine.

BACKGROUND

Atogepant is an oral, small-molecule, calcitonin gene-related peptide receptor antagonist approved for the preventive treatment of episodic migraine.

METHODS

A 52-week, multicenter, randomized, open-label trial of adults (18-80 years) with migraine. Lead-in trial completers or newly enrolled participants with 4-14 migraine days/month were enrolled and randomized (5:2) to atogepant 60 mg once daily or oral standard care (SC) migraine preventive medication. The primary objective was to evaluate the safety and tolerability of atogepant; safety assessments included treatment-emergent adverse events (TEAEs), clinical laboratory evaluations, vital signs, and Columbia-Suicide Severity Rating Scale scores. Efficacy assessments (atogepant only) included change from baseline in mean monthly migraine days (MMDs) and the proportion of participants with reductions from baseline of ≥50%, ≥75%, and 100% in MMDs.

RESULTS

The trial included 744 participants randomized to atogepant 60 mg (n = 546) or SC (n = 198). The atogepant safety population was 88.2% female (n = 479/543) with a mean (standard deviation) age of 42.5 (12.0) years. TEAEs occurred in 67.0% (n = 364/543) of participants treated with atogepant 60 mg. The most commonly reported TEAEs (≥5%) were upper respiratory tract infection (10.3%; 56/543), constipation (7.2%; 39/543), nausea (6.3%; 34/543), and urinary tract infection (5.2%; 28/543). Serious TEAEs were reported in 4.4% (24/543) for atogepant. Mean (standard error) change in MMDs for atogepant was -3.8 (0.1) for weeks 1-4 and -5.2 (0.2) at weeks 49-52. Similarly, the proportion of participants with ≥50%, ≥75%, and 100% reductions in MMDs increased from 60.4% (310/513), 37.2% (191/513), and 20.7% (106/513) at weeks 1-4 to 84.2% (282/335), 69.9% (234/335), and 48.4% (162/335), at weeks 49-52.

CONCLUSION

Daily use of oral atogepant 60 mg for preventive treatment of migraine during this 1-year, open-label trial was safe, well tolerated, and efficacious.

Two-year effectiveness of erenumab in resistant chronic migraine: a prospective real-world analysis

Background

Controlled and real-world evidence have demonstrated the efficacy of calcitonin gene related peptide (CGRP) monoclonal antibodies (MABs) in migraine. However, data on the over-one-year sustained effectiveness of CGRP MABs in resistant chronic migraine (CM) is sparse. 

Methods

This is a two-year real-world prospective analysis of an ongoing single centre audit conducted in patients with resistant CM. Patients received monthly erenumab for six months before assessing its effectiveness. Responders were considered those who achieved at least 30% reduction in monthly migraine days (MMD) by month 6, compared to baseline. Secondary outcomes were also analysed, including changes of the Headache Impact Test version 6 (HIT-6).

Results

One hundred sixty-four patients [135 (82.3%) females; mean age 46 SD 14) years] were included in the audit and 160 patients analysed. Patients had failed a mean of 8.4 preventive treatments at baseline. At month 6, 76 patients (48%) were 30% responders to erenumab, 50 patients (31%) were 50% responders and 25 (15%) were 75% responders. The mean reduction in MMD at month 6 was 7.5 days compared to baseline (P < 0.001). At month 12 and month 18, 61 patients (38%) and 52 patients (33%) remained 30% responders respectively. At month 24, 36 patients (23%) remained 30% responders, 25 patients (16%) and 13 patients (8%) were respectively 50% and 75% responders. Compared to 95% of patients at baseline, at months 6, 12 and 24, 46%, 29% and 16% of responders respectively had severe disability. At least one adverse event at month 6, 12, 18 and 24 was reported by 49%, 19%, 11% and 3% of patients. By month 6, 13% of patients discontinued the treatment because of side effects, often constipation.

Conclusions

Long-term sustained effectiveness of erenumab was reported only by a minority of resistant CM patients. Although more research in resistant migraine is needed, Erenumab can provide long-term meaningful reduction in migraine load and migraine-related disability in some patients.

Calcitonin gene-related peptide in migraine: from pathophysiology to treatment

INTRODUCTION

It has been observed in recent years that levels of such molecules as calcitonin gene-related peptide (CGRP) and, to a lesser extent, the pituitary adenylate cyclase-activating peptide are elevated during migraine attacks and in chronic migraine, both in the cerebrospinal fluid and in the serum. Pharmacological reduction of these proteins is clinically significant, with an improvement in patients' migraines. It therefore seems logical that one of the main lines of migraine research should be based on the role of CGRP in the pathophysiology of this entity.

DEVELOPMENT

The Spanish Society of Neurology's Headache Study Group decided to draft this document in order to address the evidence on such important issues as the role of CGRP in the pathophysiology of migraine and the mechanism of action of monoclonal antibodies and gepants; and to critically analyse the results of different studies and the profile of patients eligible for treatment with monoclonal antibodies, and the impact in terms of pharmacoeconomics.

CONCLUSIONS

The clinical development of gepants, which are CGRP antagonists, for the acute treatment of migraine attacks, and CGRP ligand and receptor monoclonal antibodies offer promising results for these patients.

Calcitonin gene-related peptide in migraine: from pathophysiology to treatment

INTRODUCTION

It has been observed in recent years that levels of such molecules as calcitonin gene-related peptide (CGRP) and, to a lesser extent, the pituitary adenylate cyclase-activating peptide are elevated during migraine attacks and in chronic migraine, both in the cerebrospinal fluid and in the serum. Pharmacological reduction of these proteins is clinically significant, with an improvement in patients' migraines. It therefore seems logical that one of the main lines of migraine research should be based on the role of CGRP in the pathophysiology of this entity.

DEVELOPMENT

The Spanish Society of Neurology's Headache Study Group decided to draft this document in order to address the evidence on such important issues as the role of CGRP in the pathophysiology of migraine and the mechanism of action of monoclonal antibodies and gepants; and to critically analyse the results of different studies and the profile of patients eligible for treatment with monoclonal antibodies, and the impact in terms of pharmacoeconomics.

CONCLUSIONS

The clinical development of gepants, which are CGRP antagonists, for the acute treatment of migraine attacks, and CGRP ligand and receptor monoclonal antibodies offer promising results for these patients.

Psychological predictors of negative treatment outcome with Erenumab in chronic migraine: data from an open label long-term prospective study

Background

Monoclonal antibodies (mABs) targeting the calcitonin gene-related peptide (CGRP) pathway represent the first disease-specific preventive migraine therapy. Growing evidence suggests that they are effective in the preventive treatment of difficult-to-treat patients. In this study, we evaluated the psychological predictors of the outcome of treatment with the anti-CGRP monoclonal antibody erenumab in patients with chronic migraine (CM).

Methods

Seventy-five patients with CM who had already failed at least 3 preventive therapies received erenumab every 28 days for a period of 12 months. Before the first administration, patients received a full psychological evaluation using The Structured Clinical Interview for DSM-5 Clinician Version (SCID-5-CV) to assess personality disturbances (primary outcome), mood and anxiety disorders, and as well specific questionnaires to evaluate alexithymia traits, childhood traumas, and current stressors (secondary outcomes).

Results

After 12 months of treatment, 53 patients reported a reduction of at least 50% in headache days/per month (Responders), whereas 22 did not (Non Responders). When compared to Responders, Non Responders were characterized by a higher prevalence of personality disorders belonging to Cluster C (avoidant, dependent, and obsessive-compulsive) (77% vs 37%, p = .001). Non Responders were also characterized by a higher prevalence of anxiety disorders (90% vs 60%, p = 0.007), showed more alexithymic traits (51.7 ± 13.7 vs 42.9 ± 14.3, p = 0.017), and reported a higher number of 'at least serious' current stressors (3.2 ± 4.0 vs 0.8 ± 1.4, p < .0001) than Responders. At the multivariate analysis, higher prevalence of Cluster C personality disorders (OR 3.697; p = 0.05) and higher number of ‘at least serious’ life events (OR 1.382; p = 0.017) arose as prognostic factors of erenumab failure.

Conclusions

Erenumab confirmed its effectiveness in a population of difficult-to-treat migraine. The presence of “anxious-fearful” personality together with current stressors and anxiety represent negative predictors of treatment outcome.

Trial registration

The study protocol was registered at clinicaltrials.gov (NCT04361721).

Ketamine in the Past, Present, and Future: Mechanisms, Metabolites, and Toxicity

PURPOSE OF REVIEW

While ketamine's analgesia has mostly been attributed to antagonism of N-methyl-D-aspartate receptors, evidence suggests multiple other pathways are involved in its antidepressant and possibly analgesic activity. These mechanisms and ketamine's role in the nociplastic pain paradigm are discussed. Animal studies demonstrating ketamine's neurotoxicity have unclear human translatability and findings from key rodent and human studies are presented.

RECENT FINDINGS

Ketamine's metabolites, and (2R,6R)-hydroxynorketamine in particular, may play a greater role in its clinical activity than previously believed. The activation of α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) and the mammalian target of rapamycin by ketamine are mechanisms that are still being elucidated. Ketamine might work best in nociplastic pain, which involves altered pain processing. While much is known about ketamine, new studies will continue to define its role in clinical medicine. Evidence supporting ketamine's neurotoxicity in humans is lacking and should not impede future ketamine clinical trials.

Ketamine for Refractory Chronic Migraine: An Observational Pilot Study and Metabolite Analysis

Patients with refractory chronic migraine have substantial disability and have failed many acute and preventive medications. When aggressive intravenous therapy is indicated, both lidocaine and (R,S)-ketamine infusions have been used successfully to provide relief. Retrospective studies have shown that both agents may be associated with short-term analgesia. In this prospective, observational pilot study of 6 patients, we compared the effects of lidocaine and (R,S)-ketamine infusions and performed metabolite analyses of (R,S)-ketamine to determine its metabolic profile in this population. One of (R,S)-ketamine's metabolites, (2R,6R)-hydroxynorketamine, has been shown in animal studies to reduce pain, but human studies in patients undergoing continuous (R,S)-ketamine infusions for migraine are lacking. All 6 patients tolerated both infusions well with mild adverse effects. The baseline mean pain rating (0-10 numeric rating scale) decreased from 7.5 ± 2.2 to 4.7 ± 2.8 by end of lidocaine treatment ( P ≤ . 05 ) but increased to 7.0 ± 1.4 by the postdischarge visit at 4 weeks (P > .05 vs baseline). The baseline mean pain rating prior to ketamine treatment was 7.4 ± 1.4, which decreased to 3.7 ± 2.3 by the end of the hospitalization ( P ≤ . 05 ) but increased to 7.2 ± 1.7 by the postdischarge visit at 6 weeks (P > .05 vs baseline). For the primary outcome the change in pain from baseline to end of treatment was greater for ketamine than lidocaine (-3.7 vs -2.8; P ≤ . 05 ), but this has minimal clinical significance. Ketamine metabolite analysis revealed that (2R,6R)-hydroxynorketamine was the predominant metabolite during most of the infusion, consistent with previous studies.

Approach to Pediatric Intractable Migraine

PURPOSE OF REVIEW

Intractable migraine in children and adolescents is a significant cause of disability and decreased quality of life (QoL) in this population. Challenges include lack of unifying definition for intractable migraine, and limited data on best-practice management in this age group, with most current treatment pathways extrapolated from adult studies or expert consensus.

RECENT FINDINGS

A comprehensive approach in the evaluation and management of intractable migraine in this age group encompasses excluding secondary causes of headache; making an accurate diagnosis; identifying and appropriately managing modifiable risk factors; and initiating appropriate pharmacologic therapy to reduce disability, improve health-related quality of life, reduce risk of progression, and develop adaptive pain coping strategies. Several strategies for management of pediatric intractable migraine including use of acute medications, bridge therapy in outpatient setting, emerging therapies for preventive therapy, and a stepwise combination therapy for management of pediatric intractable migraine in emergency and inpatient setting are presented based on available clinical data, safety/tolerability, availability, cost-effectiveness, and expert consensus. This descriptive review of the available literature focuses on approach to therapy for acute intractable migraine in a pediatric population including outpatient, emergency department (ED), and inpatient management.

Chronic Migraine Preventive Treatment by Prefrontal-Occipital Transcranial Direct Current Stimulation (tDCS): A Proof-of-Concept Study on the Effect of Psychiatric Comorbidities

Chronic migraine (CM) is often complicated by medication overuse headache (MOH) and psychiatric comorbidities that may influence the clinical outcome. This study aimed to investigate the relationship between psychiatric comorbidities and the effect of transcranial direct current stimulation (tDCS) in patients with CM with or without MOH. We recruited 16 consecutive CM patients who had an unsatisfactory response to at least three pharmacological preventive therapies. They were treated with anodal right-prefrontal and cathodal occipital tDCS (intensity: 2 mA, time: 20 min) three times per week for 4 weeks. All patients underwent a psychopathological assessment before and after treatment, and five of them were diagnosed with bipolar disorder (BD). After treatment, all the patients showed a significant decrease of severe and overall headache days per month. Despite having a higher migraine burden at baseline, patients with CM and BD showed a significantly greater reduction of severe headaches and psychiatric symptoms. Overall, tDCS seems to be effective in the treatment of CM patients with a poor response to different classes of pharmacological therapies, whereas BD status positively influences the response of migraineurs to tDCS.

Identifying and managing refractory migraine: barriers and opportunities?

The term refractory migraine has been used to describe persistent headache that is difficult to treat or fails to respond to standard and/or aggressive treatments. This subgroup of migraine patients are generally highly disabled and experience impaired quality of life, despite optimal treatments. Several definitions and criteria for refractory migraine have been published, but as yet, an accepted or established definition is not available. This article reviews the published criteria and proposes a new set of criteria. The epidemiology, pathophysiology and management options are also reviewed.

Risk and Predisposing Factors for Suicide Attempts in Patients with Migraine and Status Migrainosus: A Nationwide Population-Based Study

Objective: To investigate the risk and risk factors for suicide attempt by patients with regular migraines (RM) and status migrainosus (SM) in Taiwan. Methods: We analyzed a subset of the National Health Insurance Research Database of Taiwan and enrolled patients (≥20 years old) who had ever received a diagnosis of RM or SM between 2000 and 2012 in the RM and SM cohort. The SM cohort included 13,605 patients, the RM cohort had 21,485 patients, and the comparison cohort contained approximately four times that many patients. We calculated the adjusted hazard ratios and 95% confidence intervals (CI) for suicide attempts after adjusting for age, sex, monthly income, urbanization level, occupation, and comorbidities. Results: The SM cohort had a 1.81-fold risk of attempting suicide (95% CI = 1.14–2.89) compared to the comparison cohort. Other factors that predispose patients with SM to attempt suicide include the following: female sex, relatively young age (<50 years old), and low monthly income (<15,000 New Taiwan Dollars, approximately equivalent to 495 US Dollars). Additionally, the risk of attempting suicide only increased in patients who had been diagnosed with SM for longer than five years. Conclusion: SM is associated with a higher risk for suicide attempt in migraineurs in Taiwan. This finding is important to clinicians and government officials seeking to prevent patients from attempting suicide in Taiwan and other similar East Asian countries.

Treating status migrainosus in the emergency setting: what is the best strategy?

INTRODUCTION

Migraine is a disabling primary headache disorder with unknown exact pathomechanism. Status migrainosus (SM) is a complication of migraine (with or without aura), representing an attack that lasts for more than 72 h. There is a paucity of data published with regard to its pathomechanism and therapeutic options.

AREAS COVERED

The authors review the literature on SM from PubMed published between 1999 and January 2018. The authors specifically look at the therapeutic possibilities of SM in the emergency department in patients that have or have not already been treated with serotonergic agents. Additional discussion is given to the rare complications of migraine.

EXPERT OPINION

SM is a devastating condition; therefore, the primary goal is to prevent its development with proper acute and prophylactic migraine medication. If this treatment fails, the patient should be treated in the emergency setting. Due to the severity of the condition, parenteral pharmacotherapy is recommended. However, high-quality randomized trials are lacking. The currently available data suggest the use of intravenous fluids, corticosteroids, magnesium sulfate, anticonvulsive drugs, nonsteroidal anti-inflammatory drugs, antiemetics, and serotonergic agents for the treatment of SM. Still, there is a need for personalized and causal therapy for migraine sufferers.

Ketamine for Refractory Headache: A Retrospective Analysis

BACKGROUND AND OBJECTIVES

The burden of chronic headache disorders in the United States is substantial. Some patients are treatment refractory. Ketamine, an N-methyl-D-aspartate antagonist, provides potent analgesia in subanesthetic doses in chronic pain, and limited data suggest it may alleviate headache in some patients.

METHODS

We performed a retrospective study of 61 patients admitted over 3 years for 5 days of intravenous therapy that included continuous ketamine to determine responder rate and patient and ketamine infusion characteristics. Pain ratings at 2 follow-up visits were recorded. An immediate responder was a patient with decrease of 2 points or greater in the numerical rating scale (0-10) from start to final pain in the hospital. Sustained response at office visits 1 and 2 was determined based on maintaining the 2-point improvement at those visits. Patients were assessed daily for pain and adverse events (AEs).

RESULTS

Forty-eight (77%) of the 61 patients were immediate responders. There were no differences regarding demographics, opioid use, or fibromyalgia between immediate responders and nonresponders. Maximum improvement occurred 4.56 days (mean) into treatment. Sustained response occurred in 40% of patients at visit 1 (mean, 38.1 days) and 39% of patients at visit 2 (mean, 101.3 days). The mean maximum ketamine rate was 65.2 ± 2.8 mg/h (0.76 mg/kg per hour). Ketamine rates did not differ between groups. Adverse events occurred equally in responders and nonresponders and were mild.

CONCLUSIONS

Ketamine was associated with short-term analgesia in many refractory headache patients with tolerable adverse events. A prospective study is warranted to confirm this and elucidate responder characteristics.

Treatment of disabling headache with greater occipital nerve injections in a large population of childhood and adolescent patients: a service evaluation

Background

Pediatric headache disorders can be extremely disabling, with marked reduction in the quality of life of children and their carers. Evidenced-based options for the treatment of primary headache disorders with preventive medication is limited and clinical outcomes are often unsatisfactory. Greater occipital nerve injections represent a rapid and well-tolerated therapeutic option, which is widely used in clinical practice in adults, and has previously shown a good outcome in a pediatric population.

Methods

This service evaluation reviewed greater occipital nerve injections performed unilaterally with 30 mg 1% lidocaine and 40 mg methylprednisolone, to treat disabling headache disorders in children and adolescents.

Results

We analyzed a total of 159 patients who received 380 injections. Of the population, 79% had chronic migraine, 14% new daily persistent headache, 4% a trigeminal autonomic cephalalgia, 3% secondary headache and one patient had chronic tension-type headache. An improvement after injection was seen in 66% (n = 105) of subjects, lasting on average 9 ± 4 weeks. Improvement was seen in 68% of patients with chronic migraine, 67% with a trigeminal autonomic cephalalgia and 59% with new daily persistent headache. Side effects were reported in 8% and were mild and transient.

Older age, female gender, chronic migraine, increased number of past preventive use, medication overuse and developing side effects were all associated with an increased likelihood of positive treatment outcome.

Conclusions

This large single centre service evaluation confirms that unilateral injection of the greater occipital nerve is a safe, rapid-onset and effective treatment strategy in disabling headache disorders in children, with a range of diagnoses and severity of the condition, and with minimal side effects.

Polypharmacy Among Headache Patients: A Cross-Sectional Study

BACKGROUND

Polypharmacy can appropriately treat multiple chronic conditions, but it can also increase potential harm. Polypharmacy information for primary headaches is minimal, despite drugs being the main tools to manage headaches.

OBJECTIVE

The aim was to evaluate the prevalence, characteristics and risk factors of polypharmacy in patients with primary headaches and examine whether these variables differ between episodic and chronic headache patients.

METHODS

We analysed polypharmacy (simultaneous use of five or more medications), medication type, comorbidity, and risk factors in 300 patients (mean age 42.81 ± 13.21 years) with primary headaches, divided into episodic and chronic, afferent to a headache centre.

RESULTS

Patients took an average of 4.37 medications. Polypharmacy was common in 40.7% of patients, and among chronic patients, it reached 58.8%. Most patients used medications (mainly nonsteroidal anti-inflammatory drugs; 73.5%) to treat acute headaches, and 30.4% of episodic and 64.7% of chronic sufferers underwent prophylactic treatment (P < 0.0001), mostly using antidepressants (77.3%). Up to 76.7% of the cohort was taking other medications, primarily for acid-related disorders (21.7%). Comorbidities were present in 59.7% of the cohort. Variables significantly associated with polypharmacy were comorbidities, prophylactic treatment, and triptans (P < 0.001).

CONCLUSIONS

Patients with primary headaches, mainly young adults, are exposed to high polypharmacy, comparable to that of the elderly. Because increased numbers of drugs increase the risk of adverse reactions, the many medications concomitantly taken by primary headache sufferers should be frequently reviewed.

Is the Generally Held View That Intravenous Dihydroergotamine Is Effective in Migraine Based on Wrong "General Consensus" of One Trial? A Critical Review of the Trial and Subsequent Quotations

BACKGROUND

The claim that parenteral dihydroergotamine (DHE) is effective in migraine is based on one randomized, placebo-controlled, crossover trial from 1986. The aim of this review was to critically evaluate the original article. It was also found to be of interest to review quotes concerning the results in the more than 100 articles subsequently referring to the article.

METHODS

The correctness of the stated effect of intravenous DHE in the randomized clinical trial (RCT) was first critically evaluated. Then, Google Scholar was searched for references to the article and these references were classified as to whether they judged the reported RCT as positive or negative.

RESULTS

The design of the RCT, with a crossover within one migraine attack, only allows evaluation of the results for the first period and the effect of DHE and placebo were quite comparable. About 151 references were found for the article in Google scholar. Among the 95 articles with a judgment on the efficacy of intravenous DHE in the RCT, 90 stated that DHE was effective or likely effective whereas only 5 articles stated that DHE was ineffective.

CONCLUSIONS

Despite a "negative" RCT, authors of subsequent articles on the efficacy of parenteral DHE overwhelmingly reported this RCT as "positive." This is probably due to the fact that the authors concluded in the abstract that DHE is effective, and to a kind of "wrong general consensus."

Refractory chronic migraine: is drug withdrawal necessary before starting a therapy with onabotulinum toxin type A?

Onabotulinum toxin A (BT-A) is now one of the authorized prophylaxis treatments for chronic migraine (CM) thanks to previous clinical trials, which usually required a pharmacologic washout as a precondition for demonstrating its efficacy. Aim of our study was to assess the efficacy in daily clinical practice of BT-A injections in refractory CM patients, regardless of medication overuse without any standardized withdrawal protocol and without stopping the ongoing prophylaxis treatment as well. We treated 44 refractory CM patients (37 females and 7 males) trimonthly without any modification in symptomatic, or prophylactic drug therapy. Main efficacy variables included number of headache, or migraine days and episodes, total cumulative headache hours, MIDAS and HIT-6 scores; all items were assessed at baseline and at the 12-, 24-, and 36-week follow-up. All variables showed a statistically significant improvement at week 36. In general, more than 50 % of patients had a good clinical outcome (including all improved patients, either partial or full responder) and that the percentage of drug abuser patients significantly decreased from 75 to 50 %, thanks to a spontaneous reduction of the symptomatic drug intake. Adverse events were uncommon and did not require treatment discontinuation. Onabotulinum toxin A treatment in refractory CM patients with unsatisfactory prophylactic drug treatments and pharmacological abuse is effective in improving clinical outcome and quality of life. This result may be achieved through a flexible pharmacologic approach tailored to each patient's needs; moreover, the patient himself can be often expected to reduce drug consumption spontaneously.

Medication overuse and chronic migraine: a critical review according to clinical pharmacology

INTRODUCTION

Chronic migraine is often complicated by medication-overuse headache (MOH), a headache due to excessive intake of acute medications. Chronic migraine and MOH are serious and disabling disorders. Since chronic migraine derives from the progression of originally episodic migraine, the fundamental therapeutic strategy is prevention. This narrative review describes how to try to prevent the development of MOH and how to manage it once it has appeared.

AREAS COVERED

A PubMed database search (from 1988 to January 2015) and a review of published studies on chronic migraine and MOH were conducted.

EXPERT OPINION

In spite of progress in migraine treatment, the prevalence of chronic headaches and MOH has not changed in the course of time. Today, a large number of migraine patients have turned to numerous expert physicians and experienced all sorts of prophylactic treatments without decisive benefits. Their condition seems to have crystallized even more as chronic and intractable. This means that to prevent chronification and MOH, we need more effective drugs and better strategies to use them. In particular, we must detect disease biomarkers and predictive factors for drug response that allow for personalized treatment when migraine is still episodic and make analgesic overuse pointless.

Emerging therapies for chronic migraine

Not all chronic migraines are medication-overuse headaches and so the challenge is how to treat them. Currently available pharmacological therapies may be ineffective or they are abandoned because of intolerable side effects. There is still much room for novel therapeutic approaches in those with drug refractory migraine (RM). Occipital nerve stimulation (ONS) and botulinum toxin type A have finally gained a level of evidence based on the results of RCTs and pooled analysis, which by and large have shown at least a modest but valuable therapeutic effect. For a long time, these two approaches were only supported by clinical experience and open-label studies. Considering the disabling nature of migraine disorder, the large prevalence and serious impact on health-related quality of life and health care costs, any degree of response to treatment is acceptable and welcomed by the patient. An important issues for future studies would be better patient selection when finding candidates for each procedure.

Targeted alteration of dietary n-3 and n-6 fatty acids for the treatment of chronic headaches: a randomized trial

Omega-3 and n-6 fatty acids are biosynthetic precursors to lipid mediators with antinociceptive and pronociceptive properties. We conducted a randomized, single-blinded, parallel-group clinical trial to assess clinical and biochemical effects of targeted alteration in dietary n-3 and n-6 fatty acids for treatment of chronic headaches. After a 4-week preintervention phase, ambulatory patients with chronic daily headache undergoing usual care were randomized to 1 of 2 intensive, food-based 12-week dietary interventions: a high n-3 plus low n-6 (H3-L6) intervention, or a low n-6 (L6) intervention. Clinical outcomes included the Headache Impact Test (HIT-6, primary clinical outcome), Headache Days per month, and Headache Hours per day. Biochemical outcomes included the erythrocyte n-6 in highly unsaturated fatty acids (HUFA) score (primary biochemical outcome) and bioactive n-3 and n-6 derivatives. Fifty-six of 67 patients completed the intervention. Both groups achieved targeted intakes of n-3 and n-6 fatty acids. In intention-to-treat analysis, the H3-L6 intervention produced significantly greater improvement in the HIT-6 score (-7.5 vs -2.1; P<0.001) and the number of Headache Days per month (-8.8 vs -4.0; P=0.02), compared to the L6 group. The H3-L6 intervention also produced significantly greater reductions in Headache Hours per day (-4.6 vs -1.2; P=0.01) and the n-6 in HUFA score (-21.0 vs -4.0%; P<0.001), and greater increases in antinociceptive n-3 pathway markers 18-hydroxy-eicosapentaenoic acid (+118.4 vs +61.1%; P<0.001) and 17-hydroxy-docosahexaenoic acid (+170.2 vs +27.2; P<0.001). A dietary intervention increasing n-3 and reducing n-6 fatty acids reduced headache pain, altered antinociceptive lipid mediators, and improved quality-of-life in this population.