Utility of Repetitive Transcranial Magnetic Stimulation for Chronic Daily Headache Prophylaxis: A Systematic Review and Meta-Analysis

PURPOSE OF REVIEW

Management of chronic daily headaches (CDH) remains challenging due to the limited efficacy of standard prophylactic pharmacological measures. Several studies have reported that repetitive transcranial magnetic stimulation (rTMS) can effectively treat chronic headaches. The objective was to determine the utility of rTMS for immediate post-treatment and sustained CDH prophylaxis.

RECENT FINDINGS

All procedures were conducted per PRISMA guidelines. PubMed, Scopus, Web of Science, and ProQuest databases were searched for controlled clinical trials that have tested the efficacy of rTMS on populations with CDH. DerSimonian-Laird random-effects meta-analyses were performed using the 'meta' package in R to examine the post- vs. pre-rTMS changes in standardized headache intensity and frequency compared to sham-control conditions. Thirteen trials were included with a combined study population of N = 538 patients with CDH (rTMS, N = 284; Sham, N = 254). Patients exposed to rTMS had significantly reduced standardized CDH intensity and frequency in the immediate post-treatment period (Hedges' g = -1.16 [-1.89, -0.43], p = 0.002 and Δ = -5.07 [-10.05, -0.11], p = 0.045 respectively). However, these effects were sustained marginally in the follow-up period (Hedges' g = -0.43 [-0.76, -0.09], p = 0.012 and Δ = -3.33 [-5.52, -1.14], p = 0.003). Significant between-study heterogeneity was observed, at least partially driven by variations in rTMS protocols. Despite the observed clinically meaningful and statistically significant benefits in the immediate post-treatment period, the prophylactic effects of rTMS on CDH do not seem to sustain with discontinuation. Thus, the cost-effectiveness of the routine use of rTMS for CDH prophylaxis remains questionable.

REGISTRATION

Protocol preregistered in PROSPERO International Prospective Register of Systematic Reviews (CRD42021250100).

The World Health Organization Intersectoral Global Action Plan on Epilepsy and Other Neurological Disorders and the headache revolution: from headache burden to a global action plan for headache disorders

The World Health Organization (WHO) Intersectoral Global Action Plan on Epilepsy and Other Neurological Disorders was developed by WHO to address the worldwide challenges and gaps in provision of care and services for people with epilepsy and other neurological disorders and to ensure a comprehensive, coordinated response across sectors to the burden of neurologic diseases and to promote brain health across life-course. Headache disorders constitute the second most burdensome of all neurological diseases after stroke, but the first if young and midlife adults are taken into account. Despite the availability of a range of treatments, disability associated with headache disorders, and with migraine, remains very high. In addition, there are inequalities between high-income and low and middle income countries in access to medical care. In line with several brain health initiatives following the WHOiGAP resolution, herein we tailor the main pillars of the action plan to headache disorders: (1) raising policy prioritization and strengthen governance; (2) providing effective, timely and responsive diagnosis, treatment and care; (3) implementing strategies for promotion and prevention; (4) fostering research and innovation and strengthen information systems. Specific targets for future policy actions are proposed. The Global Action Plan triggered a revolution in neurology, not only by increasing public awareness of brain disorders and brain health but also by boosting the number of neurologists in training, raising research funding and making neurology a public health priority for policy makers. Reducing the burden of headache disorders will not only improve the quality of life and wellbeing of people with headache but also reduce the burden of neurological disorders increasing global brain health and, thus, global population health.

Calcitonin Gene-Related Peptide Monoclonal Antibody Use for the Preventive Treatment of Refractory Headache Disorders in Adolescents

BACKGROUND

Monoclonal antibodies to calcitonin gene-related peptide or its receptor have clinical trial evidence in adults with headache, but data are lacking in adolescents. The objective of this study was to describe the safety and efficacy of calcitonin gene-related peptide monoclonal antibody treatment in adolescents with chronic headache disorders.

METHODS

We performed a retrospective multisite cohort study of patients less than 18 years of age who received a calcitonin gene-related peptide monoclonal antibody for headache prevention. Demographics, baseline headache characteristics, efficacy, and side effect data were collected.

RESULTS

The study population comprised 112 adolescents who received at least one dose of a calcitonin gene-related peptide monoclonal antibody. Mean (S.D.; range) age at first dose was 15.9 years (1.4; 10.3 to 17.8). Ninety-four patients (83.9%) had chronic migraine, 12 (10.7%) had new daily persistent headache, and six (5.4%) had persistent post-traumatic headache. At baseline, the mean (S.D.) number of headache days per month was 26.9 (6.1) (n = 109) and headache was continuous in 75 of 111 (67.6%). At first follow-up visit there was a significant reduction in headache frequency compared with baseline (-2.0 days; 95% confidence interval, -0.8 to -3.2). Significant benefit was perceived by 29.5% of patients at first follow-up visit (n = 33/112) and 30.1% (n = 22/73) at second follow-up visit. A significant functional improvement was perceived by 31% of patients (n = 31/94) at the first follow-up visit and 22.4% (n = 15/67) at the second follow-up visit. The most common side effects were injection site reactions in 17.0% (n = 19) and constipation in 8.0% (n = 9). Five patients (4.5%) discontinued because of side effects.

CONCLUSIONS

Side effects with calcitonin gene-related peptide monoclonal antibody treatment in adolescents were similar to those reported in adult trials. Calcitonin gene-related peptide monoclonal antibody treatment appears to benefit a proportion of adolescents with chronic refractory headache disorders.

Acupuncture as prophylaxis for chronic migraine: a protocol for a single-blinded, double-dummy randomised controlled trial

INTRODUCTION

Approximately 1.4%-2.2% of the global population suffers from chronic migraine. Acupuncture may serve as an alternative management for chronic migraine, where pharmacological prophylaxis is not suitable. However, the effects of acupuncture as migraine prophylaxis have not been confirmed. This study is designed as a single-blinded, double-dummy randomised controlled trial to evaluate the efficacy and safety of acupuncture compared with topiramate in patients with chronic migraine.

METHODS AND ANALYSIS

A total of 60 participants will be randomly assigned to two different groups. Participants will receive verum acupuncture and placebo medicine in the treatment group, while participants in the control group will be treated with sham acupuncture and real medicine (topiramate). All participants will receive a 12-week treatment and then be followed up for another 12 weeks. The primary outcome is the reduction of monthly headache days, and the secondary outcomes include the reduction of the number of days with acute headache medications, and changes of Migraine Disability Assessment, Migraine-Specific Quality of Life Questionnaire, Headache Impact Test, State-Trait Anxiety Inventory-trait, and Beck Depression Inventory-II scores from baseline to endpoints.

ETHICS AND DISSEMINATION

Ethical approval of this study was granted by the Research Ethical Committee of Beijing Hospital of Traditional Chinese Medicine Affiliated to Capital Medical University (2017BL-045-01). Written informed consent will be obtained from all participants. Outcomes of the trial will be disseminated through peer-reviewed publications.

TRIAL REGISTRATION NUMBER

ISRCTN13563102; Pre-results.

Intravenous dexamethasone to prevent the recurrence of benign headache after discharge from the emergency department: a randomized, double-blind, placebo-controlled clinical trial

Objective:

To evaluate whether the addition of intravenous (IV) dexamethasone to standard emergency department (ED) benign headache therapy would reduce the incidence of headache recurrence at 48–72 hours.

Methods:

This randomized, double-blind, placebo-controlled clinical trial of adult patients presenting with the chief complaint of headache was conducted in the ED of 2 academic, urban Level 1 hospitals. Headache evaluation and therapy were determined by the treating physician, and, before discharge, patients were administered either 10 mg of IV dexamethasone or placebo. The treatment groups had similar baseline characteristics, abortive therapy, IV fluids and degree of pain relief achieved before discharge. Patients were contacted 48–72 hours following discharge and asked whether their headache was “better,” “worse” or “remained unchanged” when compared with their symptoms at discharge. Those whose headaches were “worse” or “unchanged,” and those who reported a return of headache after being pain free at discharge were considered to be treatment failures and classified as having had a recurrence. The patient's headache at follow-up was further categorized as severe (i.e., provoking another physician visit or interfering with daily activity) or mild (i.e., requiring self-medication or no treatment).

Results:

Fifty-seven patients met the inclusion criteria and 2 were lost to follow-up, leaving 55 for analysis. At follow-up, 9.7% (3/31) of those receiving dexamethasone had headache recurrence, versus 58.3% (14/24) of those receiving placebo (p< 0.001). Four dexamethasone recipients (12.9%) had severe headaches at follow-up compared with 8 (33.3%) in the placebo group (p= 0.14).

Conclusions:

In this study, IV dexamethasone reduced headache recurrence at 48–72-hour follow-up. Given its excellent safety profile and likely benefit, IV dexamethasone should be considered for ED headache patients after standard evaluation and therapy.

[Positioning of headache units in the field of neurology: the importance of OnabotulinumtoxinA and other therapies in the treatment of headaches]

Chronic migraine is a disease that affects 0.5-2.5% of the population, depending on the statistics that are analysed and the definition of chronic migraine that is used. It is extraordinarily disabling, since it does not allow the sufferer to carry out any of their scheduled personal, professional or social activities, and it has a great impact on the patients' quality of life, as measured on disability, quality of life and impact on daily activities scales. Yet, nowadays there are treatments that have proven to be effective in cases of chronic migraine, such as OnabotulinumtoxinA. It is a treatment that is well tolerated and with a high rate of efficacy. Yet it is not only a therapeutic tool, but in the world of headaches it has also opened up the doors to invasive treatments, to the learning of techniques and, in short, to placing headaches in referral units that are usually located in tertiary care hospitals. Furthermore, it has also helped to overcome the idea that patients with headache should be visited exclusively by primary care physicians or general neurologists. This is an opportunity to redefine the field of study and the care for headaches that must be seized. In the future, this is going to be complemented by novel treatments with neurostimulation and probably with monoclonal antibodies against the calcitonin gene-related peptide. A revolution has begun in our knowledge and capacity to act. It is our duty to give it the importance and usage it deserves both for our patients and for us as specialists.

[Does medication abuse in patients with chronic migraine influence the effectiveness of preventive treatment with topiramate?]

INTRODUCTION

Patients with chronic migraine (CM) and medication abuse are difficult to treat, and have a greater tendency towards chronification and a poorer quality of life than those with other types of headache.

AIM

To evaluate whether the presence of medication abuse lowers the effectiveness of topiramate.

PATIENTS AND METHODS

A series of patients with CM were grouped according to whether they met abuse criteria or not. They were advised to stop taking the drug that they were abusing. Treatment was adjusted to match their crises and preventive treatment with topiramate was established from the beginning. The number of days with headache and intense migraine in the previous month and at four months of treatment was evaluated.

RESULTS

In all, 262 patients with CM criteria were selected and 167 (63.7%) of them fulfilled abuse criteria. In both groups there was a significant reduction in the number of days with headache/month and number of migraine attacks/month at the fourth month of treatment with topiramate. The percentage of reduction in the number of days with headache/month in CM without abuse was 59.3 ± 36.1%, and with abuse, 48.7 ± 41.7% (p = 0.0574). The percentage of reduction in the number of days with intense migraine/month in CM without abuse was 61.2%, and with abuse, 50% (p = 0.0224). Response rate according to the number of days with headache/month in CM without abuse was 69%, and with abuse, 57%. Response rate according to the number of intense migraines/month in CM without abuse was 76.8%, and in CM with abuse, 61% (p = 0.0097).

CONCLUSIONS

Topiramate was effective in patients with CM with and without medication abuse, although effectiveness is lower in the latter case.

Responding to the refusal of care in the emergency department

The emergency department (ED) serves as the primary gateway for acute care and the source of health care of last resort. Emergency physicians are commonly expected to rapidly assess and treat patients with a variety of life-threatening conditions. However, patients do refuse recommended therapy, even when the consequences are significant morbidity and even mortality. This raises the ethical dilemma of how emergency physicians and ED staff can rapidly determine whether patient refusal of treatment recommendations is based on intact decision-making capacity and how to respond in an appropriate manner when the declining of necessary care by the patient is lacking a basis in informed judgment. This article presents a case that illustrates the ethical tensions raised by the refusal of life-sustaining care in the ED and how such situations can be approached in an ethically appropriate manner.

[Botulinum toxin A in chronic refractory migraine: premarketing experience]

INTRODUCTION

Chronic migraine is very disabling, with medication overuse commonly associated. The recent approval of botulinum toxin-A -OnabotulinumtoxinA (OnabotA)- means a hallmark.

AIM

To describe our experience in compassionate use before approval.

PATIENTS AND METHODS

35 cases with chronic migraine assessed between July 2009-December 2011 in a specialized headache consultation. 100 U of OnabotA were injected in 21 points over the facial and pericranial muscles, according to a modified PREEMPT protocol. We determined before and after treatment: number of episodes and migraine days; pain intensity and days of disability extracted from MIDAS score, and data regarding drug intake. After follow-up, new injections were given at intervals dictated by individualized response timing. Therapeutic response was considered when: intensity of pain was reduced to a half o ≥ 4 VAS points, or the number of monthly days of pain descended ≥ 7/month, or the case converted to non-drug overuser.

RESULTS

In 27 cases (80%) it was proved clinical improvement. This effect was confirmed by: a reduction in headache severity, reflected as much in pain intensity (VAS scale < 0.001) as in the number of days with disability (3.2 vs 0.4, p < 0.001); an improvement in the number of monthly days of pain (19.8 vs 13.8, p < 0.05; a significant decrease in the number of cases of medication overuse (69% vs 13%, p < 0.01). Mean duration of effect was 15 weeks and mean follow-up 9.8 months.

CONCLUSIONS

OnabotA disclosed efficacy as prophylactic treatment of chronic migraine. It is mainly expressed as a reduction of pain intensity. Medication overuse also descended. Adverse events were sparse.

Non-pharmacological and pharmacological prevention of episodic migraine and chronic daily headache

Episodic Migraine and Chronic Daily Headache are common disorders affecting millions of Americans, with a significantly disproportionate affect on women. West Virginia, due to its high obesity rates and lower socioeconomic status, is likely more heavily affected by these conditions. Prevention of episodic migraine goes well beyond the limited scope of medications and includes many areas which physicians need to be knowledgeable, including lifestyle modifications, trigger avoidance, and relaxation therapies. The prevention of progression of episodic headaches to chronic headaches includes a number of options, possibly most importantly the prevention of medication overuse from either over-the-counter or prescription medications. Despite limited evidence based pharmacologic options for the prevention of headaches, there are many safe and effective mechanisms in which physicians can help their patients limit the burden of migraine and prevent the progression toward chronic daily headache.

Management of daily headache unresponsive to preventive treatment: daily triptans versus daily opioids

Daily headache affects an estimated 3% to 6% of the general population and affects women 2 to 3 times more frequently than men. The vast majority of daily headache is nonparoxysmal, or chronic daily headache. In the general population, the distribution of chronic tension-type headache and chronic migraine is fairly equal, but in medical practice chronic migraine accounts for the vast majority of nonparoxysmal daily headache. The first step in the management of chronic daily headache is to identify potential overuse of analgesic and vasoconstrictor medications. Preventive treatment is then initiated with a tricyclic antidepressant, beta-blocker, calcium-entry blocker, and/or anticonvulsant. Chronic migraine patients who are refractory to specific headache treatment may take a triptan frequently, if not daily, or a (long-acting) opioid. Both management strategies of refractory daily headache are controversial but appear safe and effective, although daily opioid treatment should be reserved for a relatively small, selected subpopulation. Through a practice survey, we looked at potential differences between daily (long-acting) opioid and daily triptan treatment in 53 patients. We found patient satisfaction with either treatment to be relatively favorable, although there was an implication that triptans outperform opioids in providing headache relief. However, it was also evident that in both treatment groups, despite the relatively positive patient satisfaction results, chronic migraine patients clearly continued to experience a negative impact from their headaches.

[Prophylactics of postpuncture syndrome after central neuroaxial blockades]

The article presents data of an analysis of anesthesiologic maintenance of 3410 cesarean sections under conditions of spinal and epidural anesthesia. A detailed examination of 378 women has shown that frequency of the development of postinjection syndrome depends on the area of the defect of dura mater and the volume of lost cerebrospinal fluid. Postinjection syndrome can be prevented by using special needles leaving a less defect in dura mater and by introduction of 10-15 ml of sterile isotonic solution of sodium chloride into the epidural space.

Botulinum toxin type a in the prophylactic treatment of transformed migraine in Taiwanese patients: a review of 30 consecutive cases

BACKGROUND

Botulinum toxin type A (BoNT-A) for the treatment of patients with various forms of migraine has been studied, but there is a paucity of data regarding the use of BoNT-A in Asian headache patients. Our study was designed to evaluate the efficacy of BoNT-A in the treatment of transformed migraine (TM) in a population of Taiwanese patients.

METHODS

We retrospectively analyzed 30 patients who underwent BoNT-A treatment for TM from July 2003 to May 2004. Of 30 patients, 14 had palpable muscle tenderness (or tender points) in the pericranial region and 16 did not. All patients received injections into the corrugator, procerus, frontalis, and temporalis muscles (a total of 30 U), while a subset of TM patients with tender points (6 of 14 patients) also received injections to additional muscles based on a follow-the-tenderness approach (mean dose, 45 U).

RESULTS

Twenty-seven of the 30 patients (90%) surveyed reported effective relief of their symptoms with BoNT-A treatment (at least a 50% reduction in the number of headache days or in headache intensity). The greatest reduction in headache days per month and headache intensity was found in TM patients with tender points who received a mean dose of 45 U compared to those who received fixed-site dosing of 30 U.

CONCLUSION

Our results suggest that BoNT-A may be an effective prophylactic treatment for TM in Taiwanese patients. Interestingly, similar efficacy was demonstrated in TM patients with tender points compared to those without tender points when an additional dose of BoNT-A was injected into the tender muscles in the former.

Migraine and depression

Investigations of migraine comorbidity have confirmed its association with diverse psychiatric conditions. This association appears to be stronger for major depression and anxiety disorders, but comorbidity has also been reported with substance abuse and certain mood disorders. This literature also indicates that greater psychiatric comorbidity exists for migraine sufferers with aura than without. There is evidence that psychiatric comorbidity is higher in transformed migraine than in episodic migraine. However, research into the possible mechanisms underlying these associations remains limited. Subjects with migraine should be carefully screened for depression, which should be managed to prevent transformation of migraine, to increase quality of life and to gain more successful migraine therapies.

Antiepileptic drugs in the prophylaxis of migraine, chronic headache forms and cluster headache: a review of their efficacy and tolerability

The studies of different antiepileptic drugs (AEDs) in the prophylaxis of episodic migraine, cluster headache (CH) and chronic headache forms (chronic daily headache, transformed or chronic migraine, chronic tension-type headache) are reviewed. The main results from published trials are summarised - focusing on responder rates as reported in placebo-controlled, double-blind studies. Most common adverse events are also discussed. This review indicated that robust evidence supports the use of sodium valproate-divalproex and of topiramate (TPM) in the prophylaxis of migraine, while definitive conclusions about the real effects of other AEDs in migraine cannot be drawn. Overall, evidence of efficacy of different AEDs in chronic headache forms and in CH is still lacking, most studies being open-label, small-sample trials. Nevertheless, encouraging data from controlled trials are emerging for TPM in the treatment of chronic headache forms.

Topiramate in patients with episodic migraine: reducing the risk for chronic forms of headache

OBJECTIVE

The aim was to evaluate whether preventive treatment with topiramate in patients with episodic migraine reduces the risk of developing chronic forms of headache.

BACKGROUND

Chronic forms of headache, including chronic migraine or medication overuse headache (MOH), are characterized by 15 or more headache days per month. Acute medication overuse has been shown to be a risk factor for developing chronic headache, but it is not known whether preventive treatment can reduce the risk of developing chronic forms of headache or the development of MOH.

METHODS

Pooled data from 3 trials in patients with episodic migraine randomized either to treatment with 100 mg topiramate per day (n = 384) or with placebo (n = 372) were analyzed with regard to the number of headache days during a prospective 4-week baseline period and the individual final 4 weeks of each patient's treatment during the planned 26-week double-blind treatment period.

RESULTS

The number of headache days per month in the topiramate versus the placebo-treated groups was 7.3 +/- 3.0 versus 7.3 +/- 3.1 during baseline and 4.1 +/- 4.2 versus 5.6 +/- 4.9 during the final 4 weeks, respectively (P < .001). At the end of the study, 8 versus 16 patients fulfilled International Headache Society criteria of chronic headache (odds ratio: 2.11, P= .082). Moreover, a significantly lower number of patients receiving topiramate treatment reported an increase in headache days per month by the end of the study when compared to placebo (66 vs 88 patients, respectively; odds ratio: 1.49, P < .05). Finally, the number of days with usage of acute medication was significantly lower in the topiramate arm compared with placebo (3.3 +/- 3.7 vs 4.3 +/- 3.6, respectively; P < .001).

CONCLUSION

Preventive treatment with topiramate in patients with episodic migraine may reduce the risk of developing chronic forms of headache.

Pharmacokinetics and interactions of headache medications, part II: prophylactic treatments

The present part II review highlights pharmacokinetic drug-drug interactions (excluding those of minor severity) of medications used in prophylactic treatment of the main primary headaches (migraine, tension-type and cluster headache). The principles of pharmacokinetics and metabolism, and the interactions of medications for acute treatment are examined in part I. The overall goal of this series of two reviews is to increase the awareness of physicians, primary care providers and specialists regarding pharmacokinetic drug-drug interactions (DDIs) of headache medications. The aim of prophylactic treatment is to reduce the frequency of headache attacks using beta-blockers, calcium-channel blockers, antidepressants, antiepileptics, lithium, serotonin antagonists, corticosteroids and muscle relaxants, which must be taken daily for long periods. During treatment the patient often continues to take symptomatic drugs for the attack, and may need other medications for associated or new-onset illnesses. DDIs can, therefore, occur. As a whole, DDIs of clinical relevance concerning prophylactic drugs are a limited number. Their effects can be prevented by starting the treatment with low dosages, which should be gradually increased depending on response and side effects, while frequently monitoring the patient and plasma levels of other possible coadministered drugs with a narrow therapeutic range. Most headache medications are substrates of CYP2D6 (e.g., beta-blockers, antidepressants) or CYP3A4 (e.g., calcium-channel blockers, selective serotonin re-uptake inhibitors, corticosteroids). The inducers and, especially, the inhibitors of these isoenzymes should be carefully coadministered.

Coexistence of TACS and Trigeminal Neuralgia: Pathophysiological Conjectures

BACKGROUND

Trigeminal autonomic cephalgias (TACs) and trigeminal neuralgia are short-lasting unilateral primary headaches whose study is providing insights into craniofacial pain mechanisms. We report on 2 patients in whom trigeminal neuralgia coexists with the TACs paroxysmal hemicrania and SUNCT.

CONCLUSION

Coexistence of trigeminal neuralgia with various TAC forms suggests a pathophysiological relationship between these short-lasting unilateral headaches.

[Headache: diagnosis and treatment]

Headache is the most common reason why patients visit a neurologist. Approximately 70% of the population suffer from headache. The symptoms in this condition are rather simple and a well-controlled therapy is mostly available, but there are still frequent failures in the diagnosis and therapy of headaches. Failures in the treatment are caused mainly by the fact the doctors are not able to set the appropriate diagnosis. It is recommended that patients with persisting headache should turn to headache centers. The therapy should be determined by the frequency and duration of the headache, its severity, the accompanying symptoms and preceding therapeutic history. This survey may be of assistance on the state-of-the-art diagnostics and therapy of headaches in neurological practice.

[Medication overuse headache]

Frequent use of symptomatic headache drugs may induce medication overuse headache. In primary care settings, medication overuse headache is the third common diagnosis of headache, next to migraine and tension-type headache. The pathophysiologic mechanisms are unknown. It is a severely disabling condition that has a huge economic impact on society. Treatment includes complete drug withdrawal, and the prognosis is good. Preventive measures and providing information to the patients are very important.

A chronopharmacological preventive treatment for sleep-related migraine headaches and chronic morning headaches: Nitric oxide supersensitivity can cause sleep-related headaches in a subset of patients

Frequent and recurrent migraine headaches can, over time, pose the additional risks of stroke, brain damage, heart failure and attention deficit. This is why prevention should always be a part of the treatment. Nitric oxide supersensitivity is the hypothesis upon which this model is based. Its role in causing migraine headaches and chronic morning headaches can be triggered by both normal and abnormal characteristics of the sleep cycle and more specifically by the release of nitric oxide that occurs towards the end of the sleep cycle. Stress and the age-related loss of sleep continuity, together with the corresponding increase in cortisol levels, potentiate delta rebound. Delta rebound results in deeper sleep intensity. It is associated with increased nitric oxide production. Increased delta rebound then causes an increase in the amount and duration of nitric oxide release at night. Migraineurs are susceptible to migraine headaches because they are supersensitive to nitric oxide. The diurnal pattern of the incidence of sleep-related headaches in a subset of the general population is caused by the effect of nitric oxide supersensitivity during the sleep cycle. The proposed treatment is for both sleep-related migraine headaches and chronic morning headaches. It consists of melatonin and moclobemide taken during the night, close the end of the sleep cycle so as to achieve the maximum concentrations. Both melatonin and moclobemide affect three important aspects of sleep-related headaches: nitric oxide supersensitivity, stress system dysfunction and sleep pathology. Both melatonin and moclobemide have demonstrated effectiveness in preventing migraine headaches. Additionally, both melatonin and moclobemide are compatible with most of the other therapeutic agents used to prevent migraine headaches and with at least 1 therapeutic agent that is used to treat migraine headaches.

Botulinum toxin type A for the prophylactic treatment of chronic daily headache: a randomized, double-blind, placebo-controlled trial

OBJECTIVES

To identify a treatment-responsive population for botulinum toxin type A (BoNTA) and to evaluate the safety and efficacy of 3 different doses of BoNTA as prophylactic treatment of chronic daily headache (CDH).

PATIENTS AND METHODS

A randomized, double-blind, placebo-controlled study of BoNTA in patients with CDH was conducted from July 6, 2001, through November 7, 2003, at 28 North American study centers. Eligible patients were injected with BoNTA at 225 U, 150 U, 75 U, or placebo and returned for additional masked treatments at day 90 and day 180. Patients were assessed every 30 days for 9 months. The primary efficacy end point was the mean change from baseline in the frequency of headache-free days at day 180 for the placebo nonresponder group.

RESULTS

For this study, 702 patients were enrolled and randomized. The primary efficacy end point was not met. Mean improvements from baseline at day 180 of 6.0, 7.9, 7.9, and 8.0 headache-free days per month were observed in the placebo nonresponder group treated with BoNTA at 225 U, 150 U, 75 U, or placebo, respectively (P=.44). An a priori-defined analysis of headache frequency revealed that BoNTA at 225 U or 150 U had significantly greater least squares mean changes from baseline than placebo at day 240 (-8.4, -8.6, and -6.4, respectively; P=.03 analysis of covariance). Only 27 of 702 patients (3.8%) withdrew from the study because of adverse events, which generally were transient and mild to moderate.

CONCLUSIONS

Although the primary efficacy end point was not met, all groups responded to treatment. The 225 U and 150 U groups experienced a greater decrease in headache frequency than the placebo group at day 240. The placebo response was higher than expected. BoNTA was safe and well tolerated. Further study of BoNTA prophylactic treatment of CDH appears warranted.

Botulinum Toxin Type A for the Prophylaxis of Chronic Daily Headache: Subgroup Analysis of Patients Not Receiving Other Prophylactic Medications: A Randomized Double‐Blind, Placebo‐Controlled Study

OBJECTIVE

To assess the efficacy and safety of botulinum toxin type A (BoNT-A; BOTOX, Allergan, Inc., Irvine, CA) for the prophylaxis of headaches in patients with chronic daily headache (CDH) without the confounding factor of concurrent prophylactic medications.

BACKGROUND

Several open-label studies and an 11-month, randomized, double-blind, placebo-controlled study suggest that BoNT-A may be an effective therapy for the prophylaxis of headaches in patients with CDH.

DESIGN AND METHODS

This was a subgroup analysis of an 11-month, randomized double-blind, placebo-controlled study of BoNT-A for the treatment of adult patients with 16 or more headache days per 30-day periods conducted at 13 North American study centers. All patients had a history of migraine or probable migraine. This analysis involved data for patients who were not receiving concomitant prophylactic headache medication and who constituted 64% of the full study population. Following a 30-day screening period and a 30-day single-blind, placebo injection, eligible patients were injected with BoNT-A or placebo and assessed every 30 days for 9 months The following efficacy measures were analyzed per 30-day periods: change from baseline in number of headache-free days; change from baseline in headache frequency; proportion of patients with at least 30% or at least 50% decrease from baseline in headache frequency; and change from baseline in mean headache severity. Acute medication use was assessed, and adverse events were recorded at each study visit.

RESULTS

Of the 355 patients randomized in the study, 228 (64%) were not taking prophylactic medication and were included in this analysis (117 received BoNT-A, 111 received placebo injections). Mean age was 42.4+/-10.90 years; the mean frequency of headaches per 30 days at baseline was 14.1 for the BoNT-A group and 12.9 for the placebo group (P=.205). After two injection sessions, the maximum change in the mean frequency of headaches per 30 days was -7.8 in the BoNT-A group compared with only -4.5 in the placebo group (P=.032), a statistically significant between-group difference of 3.3 headaches. The between-group difference favoring BoNT-A treatment continued to improve to 4.2 headaches after a third injection session (P=.023). In addition, BoNT-A treatment at least halved the frequency of baseline headaches in over 50% of patients after three injection sessions compared to baseline. Statistically significant differences between BoNT-A and placebo were evident for the change from baseline in headache frequency and headache severity for most time points from day 180 through day 270. Only 5 patients (4 patients receiving BoNT-A treatment; 1 patient receiving placebo) discontinued the study due to adverse events and most treatment-related events were transient and mild to moderate in severity.

CONCLUSIONS

BoNT-A is an effective and well-tolerated prophylactic treatment in migraine patients with CDH who are not using other prophylactic medications.

Botulinum Toxin Type A (BOTOX ® ) for the Prophylactic Treatment of Chronic Daily Headache: A Randomized, Double‐Blind, Placebo‐Controlled Trial

OBJECTIVE

The objective of this study was to evaluate the safety and efficacy of botulinum toxin type A (BoNT-A; BOTOX, Allergan, Inc.) for the prophylactic treatment of chronic daily headache (CDH).

BACKGROUND

Several open-label and small controlled trials suggest that BoNT-A may be effective in the prophylactic treatment of headache.

DESIGN AND METHODS

This was an 11-month, randomized double-blind, placebo-controlled study of BoNT-A for the treatment of patients aged 18 to 65 years old with 16 or more headache days per 30 days conducted at 13 North American study centers. Following a 30-day screening period and a 30-day, single-blind, placebo-response period to identify placebo responders, eligible patients from both the placebo responder and placebo nonresponder groups were injected with BoNT-A or placebo every 90 days and assessed every 30 days for 9 months, a period encompassing three treatment cycles. The primary efficacy measure was the change from baseline in the frequency of headache-free days in a 30-day period for the placebo nonresponder group at day 180, the chosen efficacy time point. The secondary efficacy measure was the proportion of patients with a decrease from baseline of 50% or more in the frequency of headache days per 30-day period for the placebo nonresponder group at day 180. The change from baseline in the frequency of headaches (per 30-day period), the proportion of patients with a decrease from baseline of 50% or greater in the frequency of headaches per 30-day period, acute medication use, and adverse events were also assessed.

RESULTS

Of 571 patients assessed over the baseline period, 355 (mean age, 43.5 years; 300/355 [84.5%] female) were enrolled and randomized. At the end of the placebo run-in period, 279 patients (79%) were classified as placebo nonresponders and 76 patients (21%) as placebo responders. Subsequently, patients were randomized within each group to receive either BoNT-A or placebo. In the placebo nonresponder stratum, the mean number of headache-free days at baseline was 5.8 (+/-4.7) for BoNT-A- versus 5.5 (+/-4.7) for placebo-treated patients. At day 180, placebo nonresponders treated with BoNT-A had an improved mean change from baseline of 6.7 headache-free days per 30-day period compared to a mean change from baseline of 5.2 headache-free days for placebo-treated patients. The between-group difference of 1.5 headache-free days favored BoNT-A treatment, although the difference between the groups was not statistically significant. However, a statistically significant difference was observed at day 180 endpoint for the secondary efficacy measure. A significantly higher percentage of BoNT-A patients had a decrease from baseline of 50% or greater in the frequency of headache days per 30-day period at day 180 (32.7% vs. 15.0%, P=.027). Also, the mean change from baseline in the frequency of headaches per 30-day period at day 180 was -6.1 for BoNT-A patients vs. -3.1 for the placebo patients (P=.013). Only 4 of 173 BoNT-A patients (2.3%) discontinued the study due to adverse events. The majority of treatment-related adverse events were transient and mild to moderate in severity.

CONCLUSIONS

BoNT-A treatment resulted in patients having, on average, approximately seven more (1 week) headache-free days compared to baseline. Although at the primary time point (day 180) the BoNT-A treatment resulted in a 1.5 between-group difference compared to placebo, this difference was not statistically significant. The treatment met secondary efficacy outcome measures, including the percentage of patients experiencing a 50% or more decrease in the frequency of headache days, in addition to statistically significant reductions in headache frequency. BoNT-A was also well tolerated in patients with CDH.

Medication overuse headache: rates and predictors for relapse in a 4-year prospective study

We present a prospective 4-year follow-up study of 96 patients with medication overuse headache following withdrawal. Complete datasets were available from 85 patients (89%) 6 months, from 79 patients (82%) 1 year and from 75 patients (78%) 4 years after withdrawal. Twenty-six patients (31%) relapsed within the first 6 months after withdrawal. The number of relapses increased to 32 (41%) 1 year and to 34 (45%) 4 years after withdrawal. The 4-year relapse rate was lower in migraine than in tension-type headache (32% vs. 91%, P<or=0.001) and combination of migraine and tension-type headache (32% vs. 70%, P<or=0.027) and also lower in patients overusing triptans than analgesics (21% vs. 71%, P<or=0.001). The study suggests that the majority of relapses occur within the first year after withdrawal and that the long-term success of withdrawal depends on the type of primary headache and the type of overused medication.

Observations of the "carry-over effect" following successful termination of chronic migraine in the adolescent with short-term dihydroergotamine, dexamethasone and hydroxyzine: a pilot study

Chronic migraine management almost always requires daily oral preventative medication with potential adverse effects. Daily oral preventative therapy may also not be effective in terminating chronic migraine. Chronic central sensitisation caused by repetitive migraine attacks in a young person may lower the threshold for future migraine episodes leading to an intractable and debilitating disease course. The objective was to determine if short–term parenteral dihydroergotamine, dexamethasone and hydroxyzine can terminate chronic migraine and be followed by a continuous respite or conversion to a more benign episodic form without the need for daily oral preventative medication (“carry–over effect”). We treated ten patients, seven adolescents and three adults, with parenteral dihydroergotamine, dexamethasone and hydroxyzine given once a week for a maximum of three weeks. No oral preventative daily medication was administered. The setting was a private practice. Chronic migraine was terminated in all 7 adolescents. Their post–treatment course was converted to a more benign episodic migraine course and no adolescent required daily oral migraine preventative therapy for significantly long carry–over post–treatment observational periods. None of the three adult chronic migraine cases could be terminated satisfactorily as they all required daily oral preventative therapy. In the adolescent group only, this strategy terminated chronic migraine and resulted in a significant carry–over effect that appeared to favourably modify the long–term course without the need for daily pharmacological, potentially toxic, preventive therapy. Although this is a very small study, which requires confirmation by a larger controlled study, our data suggest a significant carryover effect in the young migraineur by administering short–term parenteral dihydroergotamine, dexamethasone and hydroxyzine.

Daily scheduled opioids for intractable head pain: long-term observations of a treatment program

BACKGROUND

Daily scheduled opioids (DSO) have been employed in some instances to remediate intractable headache. However, long-term studies of effectiveness, sequelae over several years, predictors of long-term benefit, comparisons of pain-related outcome measures, and prevalence of problematic drug behavior are not available.

METHODS

The authors evaluated the results of a treatment program at their institution designed to treat and monitor intractable headache patients administered DSO. Of 160 sequential patients participating in the program, 70 who remained on DSO for at least 3 years qualified for inclusion in an efficacy analysis. Patients completed structured questionnaires at each medical visit as part of routine clinical care. The authors assessed medical records during treatment, and during the 2 years before starting DSO. The primary clinical efficacy variable was percentage improvement in the severe headache index (frequency x severity of severe headaches/week).

RESULTS

Analysis of the medical records found 41 (26%) of the original 160 patients with >50% improvement. Patients reported larger improvements on a visual analog scale (mean improvement = 70%) than shown by the medical record (mean improvement = 46%), p < 0.00001. Problem drug behavior (dose violations, lost prescriptions, multisourcing) occurred in 50% of patients, usually involving dose violations.

CONCLUSIONS

For a select group of intractable headache patients, DSO can offer significant benefit. However, 74% of those treated either failed to show significant improvement or were discontinued from the program for clinical reasons. The relatively low percentage of patients with demonstrated efficacy and unexpectedly high prevalence of misuse have clinical relevance.

Migraine and chronic daily headache management: a qualitative study of patients' perceptions

AIM

The aim of the study was to gain insight into the patients' perceptions of migraine and chronic daily headache (CDH) management.

METHODS

Thirteen, semi-structured and individual interviews with seven migraine and five CDH patients were carried out and analysed in QSR NUD*IST5, using a grounded theory methodology.

RESULTS

The participants described using five areas of management: 1) health care use; 2) medication use; 3) alternative therapies; 4) social support; and 5) lifestyle and self-help. The participants described their expectations, preferences, worries and (dis)satisfaction in relation to these five areas of management. The participants adapted headache management to suit their needs and preferences, making migraine and CDH management highly individual and giving the headache patient a central role within their own care.

CONCLUSION

Health care is changing towards a greater involvement of the patients in their own care. Therefore, it is important to increase understanding of the patients' perspective of chronic diseases, including migraine and CDH. The results from this study inform health care professionals of the range of their patients' needs and preferences. This knowledge can be used to shape clinical practice, to develop patient education programmes and to further research efforts into issues that are important to the headache patient.

The Trager approach in the treatment of chronic headache: a pilot study

CONTEXT

Although the traditional treatment of headache has been pharmacological, there have been many attempts to treat headaches with other methods with mixed levels of success.

OBJECTIVE

To obtain preliminary data on the efficacy of the Trager approach in the treatment of chronic headache.

DESIGN

Small-scale randomized controlled clinical trial.

SETTING

University-based clinic.

PATIENTS

Thirty-three volunteers with a self-reported history of chronic headache with at least one headache per week for at least 6 months.

INTERVENTIONS

Medication only control group, medication and attention control group, and medication and Trager treatment group.

MAIN OUTCOME MEASURES

Self-reported frequency, duration, and intensity of headache, medication usage and headache quality of life (HQOL) obtained at baseline and after a 6-week treatment period.

RESULTS

Analyses of variance demonstrated significant improvement in HQOL for the Trager and attention control groups, and reduction in medication usage for the Trager group (P < 0.05). Within-group analyses revealed that participants randomized to Trager demonstrated a significant decrease in the frequency of headaches (P = 0.045), improvement in HQOL (P = 0.045), and a 44% decrease in medication usage (P = 0.03). Participants randomized to the attention control group demonstrated a significant improvement in HQOL (P = 0.035) and a 19% decrease in medication usage (P = 0.15). Participants randomized to the no-treatment control group revealed a significant increase in headache duration (P = 0.025) and intensity (P = 0.025), and a declination in HQOL (P = 0.035).

CONCLUSIONS

The Trager approach decreased headache frequency and medication usage. Trager and physician attention improved HQOL. A larger, multi-site study is recommended.

Botulinum Neurotoxin Type A in the Preventive Treatment of Refractory Headache: A Review of 100 Consecutive Cases

OBJECTIVES

To review the efficacy of botulinum neurotoxin type A (BoNT-A) in the preventive treatment of refractory headache.

BACKGROUND

Even after receiving expert care, some patients with refractory headache continue to have high disability and persistent headaches.

METHODS

Clinical records and headache calendars of 100 patients fulfilling the following inclusion criteria were reviewed: (1) age from 18 to 65 years; (2) primary headache with previous failure of at least four preventive treatments; and (3) have received BoNT-A and have been followed for at least 6 months after the BoNT-A injections. BoNT-A (100 units) was diluted in 4-cc normal saline. The muscles injected included some or all of the following: frontalis, temporalis, corrugator, procerus, occipitalis, semispinalis, splenius capitis, trapezius, cervical paraspinalis, and sternocleidomastoid. Migraine-related disability was assessed using the Migraine Disability Assessment (MIDAS) questionnaire.

RESULTS

There was a statistically significant reduction of the frequency of headache days 1 month after BoNT-A was administered (14.2 vs 28.2 days at the baseline, P <.001), which was maintained through the 3 months of study; similarly, a significant reduction in the headache index (22.3 vs 40.3, P <.001) and number of severe days with headache per month (2.6 vs 7.4, P <.001) were found at 1 month and maintained through the 3 months of study. MIDAS scores were reduced from 34.5 at baseline to 15.9 at 3 months (P <.001). A similar pattern was found in those overusing versus nonoverusing acute medication, though the response was more dramatic in the nonoverusing subgroup.

CONCLUSION

BoNT-A may play a role in the preventive treatment of refractory headache. A significant number of patients showed decrease in clinically important measurements of their headaches as well as reduced headache-related disability with this treatment. Prospective, controlled studies must be considered for severely disabled, refractory patients.

Medication-overuse headache: a worldwide problem

Medication overuse and subsequent medication-overuse headache (MOH) is a growing problem worldwide. Epidemiological data suggest that up to 4% of the population overuse analgesics and other drugs for the treatment of pain conditions such as migraine and that about 1% of the general population in Europe, North America, and Asia have MOH. Recent clinical studies gave further insights in clinical and pharmacological features, such as critical monthly doses and frequencies. These features seem to vary significantly and depend on the primary headache disorder and the type of drug that is overused. Along with these findings the new international classification of headache disorders has now incorporated additional criteria and new headache entities that will facilitate the diagnosis of MOH. Withdrawal therapy is the only treatment for this disorder and clear restriction of monthly doses is the central requirement for successful prevention.

Off‐Label Prescribing of Drugs in Specialty Headache Practice

OBJECTIVE

To assess the extent of off-label prescribing in specialty headache practice.

METHODS

A prospective record was kept of all prescriptions written during a 30-day period in a tertiary care headache program affiliated with two teaching hospitals. Each drug was categorized as "on-label," defined as approved by the FDA for a headache or general pain indication, and used in accordance with label instructions, or "off-label," defined as any use of a drug not covered in the FDA-approved package insert.

RESULTS

A total of 379 prescriptions were written during a 30-day period. One hundred and seventy-eight prescriptions (47%) met the criteria for off-label use. In all, 23 categories of off-label treatment were prescribed during the study, but just 4 accounted for over half of all off-label prescriptions: newer antiepileptic drugs such as topiramate and lamotrigine (each accounted for n = 26, 15% of off-label prescriptions), newer antidepressants, especially venlafaxine (n = 27; 15% of off-label prescriptions), and botulinum toxin type A (n = 13; 7% of off-label prescriptions). Two hundred and one prescriptions met criteria for on-label use. The largest percentages of prescriptions written for approved, on-label indications were for triptans (n = 74; 37% of on-label prescriptions), and nonsteroidal anti-inflammatory drugs (n = 64; 32% of on-label prescriptions).

CONCLUSIONS

Off-label prescribing is common in the specialty management of headache conditions. We conclude that it is within the current standard of care, and an integral part of practice, to use off-label medications in the treatment of complex headache conditions.

Botulinum toxin in migraine prophylaxis

Migraine is a chronic headache disorder manifesting in attacks lasting 4-72 hours. Characteristics of headache are unilateral location, pulsating quality, moderate or severe intensity, aggravation by routine physical activity, and association with nausea, photophobia and phonophobia. The migraine aura is a complex of neurological symptoms, which occurs just before or at the onset of migraine headache. Botulinum toxin A represents a completely new option for patients with chronic pain conditions. Numerous retrospective open-label chart reviews and 4 double-blind, placebo-controlled studies have demonstrated that botulinum toxin type A is significantly effective in migraine prophylaxis and reduces the frequency, severity, and disability associated with migraine headaches. Studies have generally reported a good and consistent efficacy. The differential therapeutic use of botulinum toxin appears to be worth attempting in migraine patients with the following characteristic features: (1) Muscular stress as migraine trigger, e. g., in craniocervical dystonia, pericranial painful muscular trigger points or tender points, oromandibular dysfunction, (2) concurrent chronic tension-type headache with the aggravating factors of muscular stress or oromandibular dysfunction, (3) chronic migraine with frequent migraine attacks on more than 15 days per month for longer than 3 months and if other therapeutic options have been either ineffective or have not been tolerated. The use of the agent does not cause CNS side effects. Migraine patients in particular, often suffer greatly, as a result of the adverse effects of the drugs used, from fatigue, dizziness, reduced concentration, loss of appetite, weight gain, hair loss and changes in libido. These side effects are not known in association with botulinum toxin A. To date, neither organic damage nor allergic complications have been reported. Thus, both the tolerability and the safety of this therapeutic measure are high. The mode of action by which botulinum toxin is effective in migraine prophylaxis is not fully understood and is under investigation. Currently, a number of other randomized, placebo-controlled, clinical trials are being conducted to evaluate the efficacy, optimal dosing, and side-effect profile of botulinum toxin type A in the prophylaxis of migraine and other headache entities.

Treatment of Primary Headache Disorders With Intravenous Valproate: Initial Outpatient Experience

OBJECTIVES

To evaluate the effectiveness of intravenous valproate in managing moderate to severe headaches.

BACKGROUND

Despite major strides in the understanding of primary headache disorders, there have been few additions to acute headache management other than introduction of the triptans. An intravenous antiepileptic preparation, sodium valproate, has been reported to be effective in the management of status epilepticus and acute headache.

METHODS

Between March 13, 2000 and October 11, 2000, we prospectively treated, in a nonrandomized and open-label study, every patient with a moderate to severe headache (4 or greater on a visual analog scale of head pain from 1 to 10) who wanted treatment with intravenous valproate. Using a verbal visual analog scale for pain (0 = no headache and 10 = most severe headache), we measured head pain before treatment and at time of discharge. The treating nurse monitored vital signs and side effects. A positive response was defined as a 50% or greater reduction at discharge in baseline pain. Information was collected regarding patient demographics, type of headache (according to criteria of the International Headache Society and that recently proposed for chronic headache), observation time in the treatment suite, cumulative dose of valproate, and use of concurrent medications. Univariable and multivariable correlates of response to treatment were identified using logistic regression analysis.

RESULTS

One hundred thirty treatments were given to 89 women and 17 men, aged 17 to 76 years; 92 patients received only one treatment. Valproate doses ranged between 300 and 1200 mg. Thirty-three patients (31%) presented with episodic migraine, with or without aura; 45 patients (42%) presented with chronic daily headache with a history of episodic migraine, with or without aura (transformed migraine); 22 (21%) with unclassifiable chronic headache; 2 (2%) with episodic cluster headache; and 4 (4%) with chronic tension-type headache. For first treatments only, 61 patients (57.5%) responded to treatment, whereas for all treatments, 82 patients (63.1%) responded. Age and gender did not affect likelihood of response, whereas increasing duration of treatment (P=.003) and the additional use of analgesics (P=.021) were each negatively associated with response. Among headache types, unclassifiable chronic headache segregated from all other classified headaches in terms of poor response. Aside from rare dizziness (n = 2) and one spell interpreted as a pseudoseizure, no side effects were noted.

CONCLUSIONS

Intravenous valproate is a safe, rapidly effective, abortive headache agent. It appears to be an effective analgesic for identifiable primary headaches, especially episodic headache, and less effective for unclassifiable chronic headache. Randomized, double-blind, controlled studies are warranted.

Gabapentin in the prophylaxis of chronic daily headache: a randomized, placebo-controlled study

OBJECTIVE

To compare efficacy and safety of gabapentin (GPT) versus placebo for prophylaxis of chronic daily headache (CDH) (headache at least 15 days/month of greater than 4 hours duration over preceding 6 months).

METHODS

This is a multicenter randomized placebo-controlled crossover study. After 4-week baseline, subjects, aged 18 to 65, were randomized to GPT 2,400 mg/day or placebo. There was 2 weeks titration, 6-week stable dosage, and 1 week washout period between treatment arms. The primary efficacy measure was the difference between the percentage of headache-free days per treatment period. Secondary efficacy measures included headache duration and severity, degree of disability, associated symptoms, concomitant medications, Visual Analogue Scale (VAS) scores, and quality of life (QOL).

RESULTS

A total of 133 patients were enrolled (41 men, 92 women, mean age 43 years). All were eligible for safety analysis. Ninety-five received sufficient treatment to allow evaluation of efficacy. There was a 9.1% difference in headache-free rates favoring GPT over placebo (p = 0.0005). Benefits for GPT were also demonstrated for headache-free days/month (p = 0.0005), severity (p = 0.03), VAS (p = 0.0006), headache-associated symptoms of nausea (p = 0.03) and photophobia/phonophobia (p = 0.04), disability affecting normal activities (p = 0.02), attacks requiring bed rest (p = 0.001), and QOL related to bodily function (p = 0.01), health/vitality (p = 0.0001), social function (p = 0.006), and health transition (p = 0.0002). Reduction in headache days/month was seen across the spectrum of prerandomization headache frequencies.

CONCLUSION

Gabapentin represents a therapeutic option for chronic daily headache.