Medication-overuse headache: a review

Complicated Form of Medication Overuse Headache Is Severe Version of Chronic Migraine

Background: MOH (medication overuse headache) is regarded as a complication of chronic migraines (CMs), with a general acknowledgment of reciprocal triggering between these two conditions. The present study aims to investigate the clinical parameters of relevance for the development of MOH among patients with CM, as well as for the subtype classification of MOHs. Method: We compared two groups of CM patients, with and without MOH, separated based on their demographic data and migraine characteristics. A subgroup of MOH accompanied by psychiatric co-morbidities (depression, anxiety, sleep disorder) was delineated, and the clinical features of relevance for the progression of MOH into the complicated state were evaluated. Results: The study revealed a higher prevalence of a family history of migraine in both the MOH and potentially complicated MOH subgroups (p < 0.001, p = 0.036), along with a higher prevalence of bilateral pain localization (p = 0.033, 0.021). Symptoms commonly associated with migraines, such as nausea, vomiting, photophobia, phonophobia, and osmophobia, were more common in both the MOH and potentially complicated MOH subgroups (p < 0.05). Furthermore, a positive correlation was found for the frequency (p < 0.001) and severity (p = 0.010) of migraine attacks and the duration of headaches (p = 0.007), atopy (p = 0.017), sleep disturbances (p = 0.011), and emotional stress (p = 0.022) in the MOH group. Conclusion: We found a positive correlation between the prevalence of MOH among patients with CM and a family history of migraines, higher frequency and intensity of headaches, bilateral manifestation, sleep disturbances, and emotional stress. Moreover, symptoms accompanying migraines were found to be more prevalent in individuals with MOH and potentially complicated MOH.

Delayed opportunities for patient-provider communication about medication overuse headache: Mixed methods perspectives from patients and neurologists

Objectives

Medication overuse headache (MOH) is a common, debilitating condition occurring when migraine patients overuse pain relief medications. We conducted a convergent mixed methods study examining patient-provider communication on MOH.

Methods

Migraine patients were identified from one academic health center via electronic health records. Research staff recruited patients and administered a remote survey on MOH awareness, knowledge, and communication; descriptive and bivariate analyses were conducted. Neurologists from the same health center were invited to participate in qualitative interviews; analysis drew from the Rapid Identification of Themes from Audio Recordings procedures. A side-by-side comparison of results followed.

Results

Participants included 200 patients and 13 neurologists. More than one third of patients (39.5 %) had never heard of 'medication overuse headache.' Among those who had, 38.4 % learned about MOH ≥ 5 years after their migraine diagnosis. Neurologists similarly reported limited patient awareness of MOH and suggested communication was provider-initiated, reactive to patient-reported symptoms and behaviors. Participants agreed MOH was described as a 'consequence' of frequent medication taking, though specific terminology varied with neurologists suggesting they choose terms they perceive to be easier to understand and less stigmatizing to patients. Neurologists felt they lacked effective patient education resources.

Conclusions

Findings reveal delayed opportunities to inform patients about MOH. Standardized education supporting early preventive communication is needed, perhaps in primary care where many patients seek initial care for migraine symptoms.

Burden of Episodic Migraine, Chronic Migraine, and Medication Overuse Headache in Alberta

OBJECTIVE

To describe demographic and clinical characteristics, healthcare resource use, costs, and treatment patterns in three migraine cohorts.

METHODS

This retrospective observational study using administrative data examined patients with episodic migraine (EM), chronic migraine (CM) (without medication overuse headache [MOH]), and medication overuse headache in Alberta, Canada. Migraine patients were identified between 2012 and 2018 based on ≥ 1 diagnostic codes or triptan prescription. Patients with CM were defined using parameter estimates of a logistic regression model, and MOH was defined as patients with an average of ≥ 15 supply days covered of acute medications. EM was defined as patients without CM or MOH. Study outcomes were summarized using descriptive statistics.

RESULTS

Patients with EM (n = 144,574), CM (n = 27,283), and MOH (n = 11,485) were included. Higher rates of healthcare use and costs were observed for CM (mean [SD] all-cause cost: ($12,693 [40,664]) and MOH ($16,611.5 [$38,748]) versus episodic migraine ($4,251 [$40,637]). Across all cohorts, opioids were the most dispensed acute medication (range across cohorts: 31.7%-89.8%), while antidepressants and anticonvulsants were the most dispensed preventive medication. Preventative medication classes were used by a minority of patients in each cohort, except anticonvulsants, where 50% of medication overuse patients had a dispensation.

CONCLUSIONS

Patients with CM and MOH have a greater burden of illness compared to patients with EM. The overutilization of acute medication, particularly opioids, and the underutilization of preventive medications highlight an unmet need to more effectively manage migraine.

Randomized controlled studies evaluating Topiramate, Botulinum toxin type A, and mABs targeting CGRP in patients with chronic migraine and medication overuse headache: A systematic review and meta-analysis

BACKGROUND

This systematic review focuses on chronic migraine patients with medication overuse headache using, respectively, topiramate, botulinum toxin type A, and human monoclonal antibodies targeting calcitonin gene-related peptide or its receptor.

METHODS

A systematic search was conducted in the databases CENTRAL, MEDLINE, Embase and Web of Science until May 2022. We included randomized controlled trials reporting the outcomes of change in monthly headache/migraine days, ≥50% response rates and change in medication overuse status. Studies were excluded if response rates were not reported. Risk of bias assessment was performed using the Cochrane RoB2 tool. The quality of evidence for outcomes across included studies was evaluated according to the five factors outlined in Cochrane GRADE approach.

FINDINGS

The initial search resulted in 1599 records. Following screening, 10 studies met our inclusion criteria, while seven studies with sufficient data were included in the meta-analysis. Studies assessing Botulinum toxin type A included 1139 patients and showed a mean reduction in headache frequency by 1.92 days per month compared to placebo (-1.92; 95% CI -2.68 to -1.16). Studies assessing human monoclonal antibodies included 1982 patients, and showed significant positive effect compared to placebo for all measured outcomes. The overall odds ratio for the ≥50% response rate was 2.90 (95% CI, 2.23 to 3.78). No significant difference was observed in the frequency of adverse effect for both Botulinum toxin type A and low dose of human monoclonal antibodies compared to placebo. There is currently insufficient evidence to determine the impact of topiramate in chronic migraine patients with medication overuse headache.

INTERPRETATION

Botulinum toxin type A and human monoclonal antibodies targeting calcitonin gene-related peptide receptor were beneficial in reducing monthly migraine days and ≥50% response rate, but uncertainties remained for Botulinum toxin type A regarding response rate. The effect size for human monoclonal antibodies was greater with relatively lower drop-out rate. High-quality randomized trials are required to evaluate the effect of topiramate in chronic migraine patients with medication overuse headache.

Socioeconomic and geographic inequalities in headache disability in Brazil: The 2019 National Health Survey

OBJECTIVE

To map the socioeconomic and geographic inequalities in headache disability in Brazil.

BACKGROUND

Headache disability and its social determinants are poorly investigated in Brazil.

METHODS

This is a secondary, cross-sectional analysis of the 2019 National Health Survey database, a representative sample of the Brazilian population. Working-aged Brazilians (aged ≥14 years) were included in the analyses (n = 225,563). Headache disability was inquired through questions on the number of days the respondent was unable to perform customary daily activities in the past 2 weeks. Proportion estimates and the mean days lost were compared between socioeconomic categories. Sample weights were used.

RESULTS

Among 14 disease-related disability groups, headache disability (n = 1228) was the second most prevalent disability in adolescents and fifth among adults aged <50 years. In the headache disability sample, there was a higher proportion of females at 72.4% (95% confidence interval [CI] 68.5%-75.9%), with a mean (95% CI) age of 41.1 (40.1-42.0) years and days lost due to disability of 3.4 (3.2-3.6) days. The sociodemographic distribution across income strata (quartiles) of the headache disability sample showed the highest proportions at the lowest income quartile in the Northeast region (15.4%, 95% CI 12.8%-18.4%), for people of Brown color (17.5%, 95% CI 14.7%-20.7%), and with the lowest education level (l3.6%, 95% CI 11.3%-16.2%). Black people, those from the North region, and those with the lowest education level had more days lost than White people (mean [95% CI] 4.1 [3.5-4.6] vs. 3.1 [2.8-3.4] days, p = 0.008), those from the Southeast region (mean [95% CI] 3.8 [3.4-4.2] vs. 2.8 [2.4-3.3] days, p = 0.022), and people with the highest education level (mean [95% CI] 3.9 [3.6-4.2] vs. 2.8 [2.3-3.3] days, p = 0.005), respectively.

CONCLUSION

In Brazil, headache disability is one of the leading causes of disability and it is characterized by socioeconomic inequalities.

Comparative Effects of Mulligan's Mobilization, Spinal Manipulation, and Conventional Massage Therapy in Cervicogenic Headache-A Prospective, Randomized, Controlled Trial

Background: There is ample evidence supporting the use of manual therapy techniques for the treatment of cervicogenic headache (CGH). Objective: The objective of this study was to find and compare the effects of different manual therapy approaches to cervicogenic headache. Methods: A randomized, controlled study was conducted on 84 CGH participants at the university hospital. The participants were divided into a Mulligan mobilization therapy group (MMT; n = 28), a spinal manipulation therapy group (SMT; n = 28), and a control group (Control; n = 28); they received the respective treatments for four weeks. The primary outcome (CGH frequency) and secondary outcomes (CGH pain intensity, CGH disability, neck pain frequency, pain intensity, pain threshold, flexion rotation (right and left), neck disability index, and quality of life scores) were measured at baseline, after 4 weeks, after 8 weeks, and at a 6-month follow-up. The one-way ANOVA test and repeated measures analysis of variance (rANOVA) test were performed to find the difference between the inter- and intra-treatment group effects. Results: Four weeks following training, the MMT group showed a statistically significant difference in the primary (CGH frequency) and secondary (CGH pain intensity, CGH disability, neck pain frequency, neck pain intensity, flexion rotation test, neck disability index, and quality of life) scores than those of the SMT and control groups (p < 0.001). The same difference was seen in the above variables at 8 weeks and at the 6-month follow-up. At the same time, the neck pain threshold level did not show any difference at the 4-week and the 8-week follow-up (p ≥ 0.05) but showed statistical difference at the 6-month follow-up. Conclusion: The study concluded that Mulligan’s mobilization therapy provided better outcomes in cervicogenic headache than those of spinal manipulation therapy and conventional massage therapy.

The impact of topiramate, botulinum toxin type A, and CGRP-antibodies on medication overuse headache in patients with chronic migraine: A protocol for systematic review and meta-analysis

Medication overuse headache (MOH) is defined as headache occurring ≥15 days/month developing as a consequence of regular overuse of acute or symptomatic headache medication for more than 3 months. MOH is present in more than 50% of patients with chronic migraine (CM). Although, studies have shown a positive impact for MOH patients of early introduction of preventive treatment and withdrawal of overused medication, uncertainties remain. The main purpose of this systematic review and meta-analysis is to assess the relative impact of topiramate, botulinum toxin type A, and human monoclonal antibodies (mAbs) targeting calcitonin gene-related peptide (CGRP) or its receptor (CGRPr) among MOH patients with CM. The PRISMA guideline for conducting systematic review will be followed. CENTRAL, MEDLINE, Embase and Web of Science databases will be searched. RCTs reporting outcomes such as change in migraine/headache frequency, change from MOH to no MOH, and ≥50% response rate will be included. The effect will be measured as mean difference (MD) for continuous data and odds ratio (OR) for dichotomous data. Heterogeneity across studies will be assessed using the Cochrane I2 statistics. The Cochrane RoB2 tool will be used to assess risk of bias, and the quality of evidence for outcomes will be rated according to five factors defined in Cochrane GRADE approach. The revision of the included articles, data extraction, risk of bias assessment, and quality rating of evidence will be independently done by two reviewers. Any discrepancies will be resolved through consensus with the third reviewer.

Analgesic abuse headache: risk factors and causes of poor adherence in the detox process

BackgroundMedication overuse headache (MOH) is characterized by a pre-existing primary or secondary headache associated with medication overuse.AimsTo identify the clinical, epidemiological, and therapeutic profiles associated with MOH and poor adherence to treatment.MethodsA cross-sectional, comparative, descriptive, analytical study was carried out to assess the characteristics of patients with MOH treated at the Hospital Geral de Fortaleza (HGF).Results103 patients participated, 95 (92.2%) women and 8 (7.8%) men. Of these, 55 (53.4%) patients answered that had already been instructed about the MOH, however they continue to abuse medication for many reasons i.e.: difficulty in bearing pain, and fear of worsening the pain. When asked about what could be done to improve adherence to treatment, in a general way, 28 (27.2%) were unable to inform, 37 (35.9%) answered that most frequent consultations could help. Furthermore, 19 (18.4%) believe that psychological counseling wound bring benefits.ConclusionThe lack of guidance or interest in the guidelines provided are real and important obstacles to treat MOH. Changes in the care model that include effective communication, more frequent return, family and psychotherapy support and close monitoring by the physician or nurses are factors that should be considered in headache clinics.  

Chronic Migraine Pathophysiology and Treatment: A Review of Current Perspectives

Chronic migraine is a disabling neurological disorder that imposes a considerable burden on individual and socioeconomic outcomes. Chronic migraine is defined as headaches occurring on at least 15 days per month with at least eight of these fulfilling the criteria for migraine. Chronic migraine typically evolves from episodic migraine as a result of increasing attack frequency and/or several other risk factors that have been implicated with migraine chronification. Despite this evolution, chronic migraine likely develops into its own distinct clinical entity, with unique features and pathophysiology separating it from episodic migraine. Furthermore, chronic migraine is characterized with higher disability and incidence of comorbidities in comparison to episodic migraine. While existing migraine studies primarily focus on episodic migraine, less is known about chronic migraine pathophysiology. Mounting evidence on aberrant alterations suggest that pronounced functional and structural brain changes, central sensitization and neuroinflammation may underlie chronic migraine mechanisms. Current treatment options for chronic migraine include risk factor modification, acute and prophylactic therapies, evidence-based treatments such as onabotulinumtoxinA, topiramate and newly approved calcitonin gene-related peptide or receptor targeted monoclonal antibodies. Unfortunately, treatments are still predominantly ineffective in aborting migraine attacks and decreasing intensity and frequency, and poor adherence and compliance with preventative medications remains a significant challenge. Novel emerging chronic migraine treatments such as neuromodulation offer promising therapeutic approaches that warrant further investigation. The aim of this narrative review is to provide an update of current knowledge and perspectives regarding chronic migraine background, pathophysiology, current and emerging treatment options with the intention of facilitating future research into this debilitating and largely indeterminant disorder.

Use of medicinal plants for headache, and their potential implication in medication-overuse headache: Evidence from a population-based study in Nepal

Background

In Nepal, traditional treatment using medicinal plants is popular. Whereas medication-overuse headache is, by definition, caused by excessive use of acute headache medication, we hypothesized that medicinal plants, being pharmacologically active, were as likely a cause.

Methods

We used data from a cross-sectional, nationwide population-based study, which enquired into headache and use of medicinal plants and allopathic medications. We searched the literature for pharmacodynamic actions of the medicinal plants.

Results

Of 2100 participants, 1794 (85.4%) reported headache in the preceding year; 161 (7.7%) reported headache on ≥15 days/month, of whom 28 (17.4%) had used medicinal plants and 117 (72.7%) allopathic medication(s). Of 46 with probable medication-overuse headache, 87.0% (40/46) were using allopathic medication(s) and 13.0% (6/46) medicinal plants, a ratio of 6.7:1, higher than the overall ratio among those with headache of 4.9:1 (912/185). Of 60 plant species identified, 49 were pharmacodynamically active on the central nervous system, with various effects of likely relevance in medication-overuse headache causation.

Conclusions

MPs are potentially a cause of medication-overuse headache, and not to be seen as innocent in this regard. Numbers presumptively affected in Nepal are low but not negligible. This pioneering project provides a starting point for further research to provide needed guidance on use of medicinal plants for headache.

Efficacy, tolerability, and safety of eptinezumab in patients with a dual diagnosis of chronic migraine and medication-overuse headache: Subgroup analysis of PROMISE-2

OBJECTIVE

To evaluate the efficacy, tolerability, and safety of eptinezumab 100 and 300 mg compared with placebo in patients with the dual diagnosis of chronic migraine (CM) and medication-overuse headache (MOH).

BACKGROUND

Eptinezumab, a humanized monoclonal antibody targeting calcitonin gene-related peptide, may be effective for treating patients with a dual diagnosis of CM and MOH.

METHODS

PROMISE-2 (NCT02974153) was a double-blind, randomized, placebo-controlled, phase 3 study that comprised a screening visit, a 28-day pretreatment period, and a 32-week study duration. Patients in this exploratory analysis of a prespecified subgroup had confirmed diagnoses of both CM and MOH at screening. Patients were randomly assigned to receive intravenous eptinezumab 100, 300 mg, or placebo every 12 weeks. Efficacy outcomes included mean changes from baseline in monthly migraine days (MMDs) during weeks 1-12, migraine responder rates at week 12, and percentages of patients below International Classification of Headache Disorders thresholds for CM and MOH over weeks 1-24.

RESULTS

There were 431 patients who were diagnosed with CM and MOH as specified in the protocol and received eptinezumab 100 mg (n = 139), 300 mg (n = 147), or placebo (n = 145). During the baseline period, these patients experienced an average of 16.7 migraine days across treatment arms. Over weeks 1-12, eptinezumab-treated patients experienced greater reductions from baseline in MMDs than placebo patients (100 mg, change from baseline = -8.4, difference from placebo [95% confidence interval (CI)] = -3.0 [-4.56, -1.52], p < 0.0001 vs. placebo; 300 mg, change from baseline = -8.6, difference from placebo [95% CI] = -3.2 [-4.66, -1.78], p < 0.0001 vs. placebo; placebo, -5.4). Compared with placebo, more eptinezumab-treated patients were ≥50% migraine responders (100 mg, 84/139 [60.4%]; 300 mg, 91/147 [61.9%]; placebo, 50/145 [34.5%]) or ≥75% responders (100 mg, 38/139 [27.3%]; 300 mg, 44/147 [29.9%]; placebo, 21/145 [14.5%]) over weeks 1-12. Therapeutic benefits with eptinezumab were observed from day 1 after dosing, and improvements were sustained with an additional dose. For the full 24-week treatment period, 71/139 (51.1%), 80/147 (54.4%), and 47/145 (32.4%) of 100, 300 mg, and placebo-treated patients, respectively, were below CM thresholds, and of the patients who provided sufficient acute medication data, 47/93 (50.5%), 53/107 (49.5%), and 26/96 (27.1%), respectively, were below medication-overuse thresholds.

CONCLUSIONS

In patients diagnosed with both CM and MOH, eptinezumab treatment resulted in greater reductions in MMDs, higher responder rates, and fewer patients meeting CM and MOH criteria, thus demonstrating the efficacy and clinical utility of eptinezumab in this patient population.

Headache in the neurology clinic: a 2-year audit

BACKGROUND

Headache is the most common reason for referral to neurology outpatient clinics in Ireland and represents approximately 30% of all new appointments.

AIM

To evaluate diagnoses and outcomes of all patients newly referred with headache to a consultant neurologist at an Irish university teaching hospital over a 2-year period.

DESIGN

A retrospective analysis and audit.

METHODS

Data including patient demographics, red flags, investigations, diagnosis, and outcome were collected on consecutive patients newly referred with headache to a consultant neurologist's outpatient clinic over a 2-year period.

RESULTS

Two hundred and seventy patients with headache were seen; 75% were women with mean age of 39 years. 89.26% (241/270) were diagnosed with a primary headache disorder alone; 4.44% (12/270) with a secondary headache disorder alone; 3.33% (9/270) with both a primary and secondary headache disorders; and 2.96% (8/270) with a painful cranial neuropathy. Migraine was the most common diagnosis, frequently associated with medication overuse. Non-attendance rates were high. Although imaging abnormalities were frequently found, on no occasion was it thought to be the cause of the headache.

CONCLUSIONS

Most patients referred to a neurology outpatient clinic with headache have a primary headache disorder. Alternate pathways should be considered to reduce the burden on Ireland's limited neurology resources without compromising patient safety.

Anandamide Is Related to Clinical and Cardiorespiratory Benefits of Aerobic Exercise Training in Migraine Patients: A Randomized Controlled Clinical Trial

Introduction: Since endocannabinoids have been implicated in migraine pathophysiology, we conducted a randomized, controlled clinical trial to test the effects of a 12-week aerobic exercise intervention on plasma anandamide (AEA) and its relation with clinical, psychological, and cardiorespiratory outcomes. Materials and Methods: Episodic migraine patients taking no preventive drugs and nonheadache individuals were recruited from Hospital São Paulo and a tertiary headache clinic between March 2012 and March 2015. Participants were randomly assigned to receive aerobic exercise or enter the waitlist. Primary outcome was changes in plasma AEA; secondary outcome was number of days with migraine/month; and other clinical variables, mood scores, and cardiorespiratory fitness were chosen as tertiary outcomes. Measurements were taken on headache-free days. Data were analyzed by generalized linear models. Discussion: Fifty participants concluded the study (mean±SD age=36.2±10.9, and BMI=26.5±4.5). The plasma AEA reduced in migraine exercise (p<0.05) and control exercise groups (p<0.01). The number of days with migraine (p<0.01), migraine attacks (p<0.05), and abortive medication used (p<0.05) reduced in the migraine exercise group, whereas cardiorespiratory fitness increased in migraine exercise and control exercise groups (both p<0.05). Anxiety, depression, anger, and fatigue scores improved in the migraine exercise group (p<0.05 for all). Significant correlations between reduction in abortive medication used and cardiorespiratory fitness (r=-0.81 p<0.001), and reduced AEA (r=0.68 p<0.05) were found. Conclusions: This study suggests that peripheral AEA metabolism may be partly linked to the clinical and cardiorespiratory benefits of regular aerobic exercise in migraine patients. Trials registration: #NCT01972607.

Maladaptive activation of Nav1.9 channels by nitric oxide causes triptan-induced medication overuse headache

Medication-overuse headaches (MOH) occur with both over-the-counter and pain-relief medicines, including paracetamol, opioids and combination analgesics. The mechanisms that lead to MOH are still uncertain. Here, we show that abnormal activation of Nav1.9 channels by Nitric Oxide (NO) is responsible for MOH induced by triptan migraine medicine. Deletion of the Scn11a gene in MOH mice abrogates NO-mediated symptoms, including cephalic and extracephalic allodynia, photophobia and phonophobia. NO strongly activates Nav1.9 in dural afferent neurons from MOH but not normal mice. Abnormal activation of Nav1.9 triggers CGRP secretion, causing artery dilatation and degranulation of mast cells. In turn, released mast cell mediators potentiates Nav1.9 in meningeal nociceptors, exacerbating inflammation and pain signal. Analysis of signaling networks indicates that PKA is downregulated in trigeminal neurons from MOH mice, relieving its inhibitory action on NO-Nav1.9 coupling. Thus, anomalous activation of Nav1.9 channels by NO, as a result of chronic medication, promotes MOH.

Medication-overuse headache

Medication-overuse headache is defined as headache occurring on more than 15days in a month in people with pre-existing primary headache, and developing as a consequence of regular overuse of acute headache treatments. Medication-overuse headache is common in general neurology clinics and can be difficult to manage. Most patients have a background of migraine, which has slowly transformed over months and years from the episodic to chronic form; with this comes an increased use of acute migraine treatment. This paper identifies who is at risk of developing medication-overuse headache, and reviews preventive measures and current treatment strategies.

The need for new acutely acting antimigraine drugs: moving safely outside acute medication overuse

Background

The treatment of migraine is impeded by several difficulties, among which insufficient headache relief, side effects, and risk for developing medication overuse headache (MOH). Thus, new acutely acting antimigraine drugs are currently being developed, among which the small molecule CGRP receptor antagonists, gepants, and the 5-HT_1F receptor agonist lasmiditan. Whether treatment with these drugs carries the same risk for developing MOH is currently unknown.

Main body

Pathophysiological studies on MOH in animal models have suggested that decreased 5-hydroxytryptamine (5-HT, serotonin) levels, increased calcitonin-gene related peptide (CGRP) expression and changes in 5-HT receptor expression (lower 5-HT_1B/D and higher 5-HT_2A expression) may be involved in MOH. The decreased 5-HT may increase cortical spreading depression frequency and induce central sensitization in the cerebral cortex and caudal nucleus of the trigeminal tract. Additionally, low concentrations of 5-HT, a feature often observed in MOH patients, could increase CGRP expression. This provides a possible link between the pathways of 5-HT and CGRP, targets of lasmiditan and gepants, respectively. Since lasmiditan is a 5-HT_1F receptor agonist and gepants are CGRP receptor antagonists, they could have different risks for developing MOH because of the different (over) compensation mechanisms following prolonged agonist versus antagonist treatment.

Conclusion

The acute treatment of migraine will certainly improve with the advent of two novel classes of drugs, i.e., the 5-HT_1F receptor agonists (lasmiditan) and the small molecule CGRP receptor antagonists (gepants). Data on the effects of 5-HT_1F receptor agonism in relation to MOH, as well as the effects of chronic CGRP receptor blockade, are awaited with interest.

Complete withdrawal is the most effective approach to reduce disability in patients with medication-overuse headache: A randomized controlled open-label trial

Background

Medication-overuse headache leads to high disability and decreased quality of life, and the best approach for withdrawal has been debated.

Aim

To compare change in disability and quality of life between two withdrawal programs.

Methods

We randomized medication-overuse headache patients to program A (two months without acute analgesics or migraine medications) or program B (two months with acute medications restricted to two days/week) in a prospective, outpatient study. At 6 and 12 months, we measured disability and headache burden by the Headache Under-Response to Treatment index (HURT). We estimated quality of life by EUROHIS-QOL 8-item at 2-, 6-, and 12-month follow-up. Primary endpoint was disability change at 12 months.

Results

We included 72 medication-overuse headache patients with primary migraine and/or tension-type headache. Fifty nine completed withdrawal and 54 completed 12-month follow-up. At 12-month follow-up, 41 patients completed HURT and 38 completed EUROHIS-QOL 8-item. Disability reduction was 25% in program-A and 7% in program-B ( p = 0.027). Headache-burden reduction was 33% in program-A and 3% in program-B ( p = 0.005). Quality of life was increased by 8% in both programs without significant difference between the programs ( p = 0.30). At 2-month follow-up, quality of life increased significantly more in program-A than program-B ( p = 0.006).

Conclusion

Both withdrawal programs reduced disability and increased quality of life. Withdrawal without acute medication was the most effective in reducing disability in medication-overuse headache patients.

Trial registration

Clinicaltrials.gov (NCT02903329).

Pediatric headache: overview

PURPOSE OF REVIEW

Headache is a common medical complaint in children and adolescents with the majority having experienced some type of headache by their teenage years. Pediatric headache presentations often differ compared to adults, and children may have difficulty describing their symptoms. Thus, a thorough understanding of the approach to the pediatric headache patient is essential to ensure appropriate diagnosis, evaluation, and management.

RECENT FINDINGS

In the following article we will review the components of a comprehensive pediatric headache assessment, as well as discuss primary and secondary headache types seen in children with focus on clinical pearls and 'red flags' necessitating diagnostic testing.

SUMMARY

Headaches in children may be due to primary or secondary etiologies. Common primary headache types include migraine or tension-type headache. Secondary headache causes are broad and include infections, trauma, vascular disorders, substance use/withdrawal, and psychiatric conditions. Current American Academy of Neurology (AAN) guidelines recommend against routine lab studies, lumbar puncture, electro-encephalogram (EEG), or neuroimaging in patients with no headache red flags by history and a normal neurologic examination.

Medication-overuse headache. Retrospective comparison of preventive treatments

ABSTRACT Objectives: Medication-overuse headache is commonly seen in tertiary centers. Limited evidence is available regarding treatment. We compared the use of one or two drugs, three drugs, or four pharmacological agents for the prevention of headache. Methods: This was a retrospective analysis of 149 consecutive patients. Sudden withdrawal and pharmacological prevention with one or more drugs were carried out. Adherence and the decrease of headache frequency of more than 50% were compared after four months between the one or two, three, and four drug groups. Results: There was no difference in adherence (p > 0.6). Headache frequency reduction was shown in 23 (54.8%, one or two drugs), 33 (70%, three drugs) and 11 (55%, four drugs); p = 0.13 and p = 0.98, not significant. There was a tendency towards significance between the one or two drug takers versus the three drug and four drug takers together (p = 0.09). Conclusions: The use of more drugs was not better at improving headache. However, there is the possibility that acting simultaneously on different sites may promote broader modulation and better outcome.

Early management of patients with medication-overuse headache: results from a multicentre clinical study

BACKGROUND AND PURPOSE

Educational intervention has proved to be effective in reducing drug abuse in uncomplicated medication-overuse headache (MOH). This ancillary of the SAMOHA multicentre study aimed to assess any differences in phenotypic characteristics, type and amount of drugs overused, and comorbidities between patients with MOH who responded to simple advice and those who did not.

METHODS

Demographic and clinical headache data of the last 3 months before enrollment of patients were collected and patients were then asked to fill out a daily headache diary for 4 weeks. Patients were then divided into two subgroups, i.e. those with confirmed MOH continued in the study [randomized (R) group], whereas those who did not still show any features of MOH dropped out of the study.

RESULTS

A total of 88 (67.7%) patients still met the inclusion criteria after the baseline 4 weeks (R group). Conversely, 42 (32.3%) patients dropped out of the study. A detailed analysis of those who dropped out revealed that only 34 were not randomized at visit 2 because they no longer satisfied the inclusion criteria for MOH [screening failures (SF) group]. The SF group was significantly younger and had fewer years of migraine history than the R group. Moreover, the SF group had a significantly shorter history of chronicity compared with the R group.

CONCLUSIONS

Our findings suggest that in MOH trials, after an educational session, an observational period is needed in order to confirm the diagnosis of MOH and to avoid overestimation of the effect of other treatments used to manage MOH. Future research should focus mainly on those patients with MOH who do not respond to simple advice and with unsuccessful withdrawal.

Predictors of successful primary care detoxification treatment for medication-overuse headache

OBJECTIVES

To investigate predictors for successful treatment outcome after a brief intervention (BI) for medication-overuse headache (MOH).

MATERIALS AND METHODS

This study evaluated predictors of successful withdrawal among patients initially participating in a pragmatic cluster-randomized controlled trial with single crossover in Norwegian general practice (the BIMOH study). BI (early or after crossover) was compared to business as usual (BAU) for the treatment of MOH. Patients were followed up 3 months after the BI.

RESULTS

In total, 46 patients had the chance to receive the BI (24 early and 22 after crossover) and were included in the predictor analyses. The mean reduction in headache and medication days/month from baseline for the BI was 6.9 (95% CI: 4.8-9.1) and 10.9 (8.1-13.6). The mean percentage reduction in headache and medication days was 30.5% (21.4-39.7) and 50.4% (39.5-61.3). Only five patients started prophylactic medication. Neither age, gender, co-occurrence of migraine, main type of overused drug at baseline nor Severity of Dependence Scale score at baseline predicted successful withdrawal in the prespecified analyses. Headache days/month and medication use at baseline were significant predictors in exploratory analyses with more headache and medication days predicting worse outcome.

CONCLUSIONS

Brief intervention for MOH is a simple and effective intervention in primary care. As the only identified predictors were frequency of headache and medication use, we conclude that treatment for all MOH patients should be attempted in primary care before referral. A raised awareness of MOH is important, as the condition is highly preventable and treatable.

TRIAL REGISTRATION

ClinicalTrials.gov identifier: NCT01314768.

Volumetric abnormalities of thalamic subnuclei in medication-overuse headache

Background

The thalamus exerts a pivotal role in pain processing and cortical excitability control and a previous voxel-based morphometry study confirmed increased volume in bilateral thalamus in medication-overuse headache (MOH). The aim of this study is to investigate altered thalamic subnuclei volume in MOH compared with normal controls, and to evaluate the relationship of each thalamic subnuclei volume with the clinical variables.

Methods

High resolution three-dimensional T1-weighted fast spoiled gradient recalled echo MR images were obtained from 27 patients with MOH and 27 normal controls (NC). Thalamic subnuclei templates were created based on Talairach template with MNI space transformation, and the individual thalamic subnuclei templates were generated by applying the deformation field from structural image segment to the thalamic subnuclei templates, and then individual thalamci subnuclei volume were calculated.

Results

The whole thalamus and each thalamic subnuclei presented increased volume compared with NC (P < 0.05). The correlation analysis demonstrated that the whole thalamus volume and each thalamic subnuclei volume showed a negative relationship with HAMD scores(P < 0.05), and no any correlation with HAMA, VAS score and disease duration (P > 0.05).

Conclusion

Increased gray matter volume in the whole thalamus and all the thalamus subnuclei may reflect central sensitization and higher-order of pain alteration in MOH. These structural changes in the thalamus may also be influenced by mood disturbances related to the MOH.

Patterns and predictors of analgesic use in pregnancy: a longitudinal drug utilization study with special focus on women with migraine

Background

Few studies have investigated the drug utilization patterns and factors predicting drug use in pregnant women with migraine. This longitudinal drug utilization study aimed to describe patterns of analgesic use in a sample of Norwegian pregnant women according to their migraine history, and to identify predictors for analgesic use among these women.

Methods

Pregnant women giving birth at Akershus University Hospital between 2008 and 2010 were recruited at ultrasound examination in gestational week 17. Data were collected by questionnaires in gestational weeks 17 and 32, and at 8 weeks postpartum, and linked to birth records. Women were grouped into four categories according to migraine history: no migraine history, previous migraine history, recent migraine history (within 1 year prior to pregnancy) and migraine in pregnancy. Patterns of use of analgesics were analyzed descriptively. Multivariable logistic regression was used to identify factors predicting analgesic use.

Results

Out of 1981 women, 5.0% reported having migraine in pregnancy, 13.2% had a recent history of migraine, 11.5% had a previous history of migraine, and 68.8% reported no history of migraine. Analgesic use declined during pregnancy. Many women switched from triptans and non-steroidal anti-inflammatory drugs to paracetamol, which constituted most of the analgesic use. Factors associated with analgesic use included recent migraine history (OR 1.6, 95% CI 1.2–2.2), more severe headache intensity (OR 1.3, 95% CI 1.3–1.4), smoking (OR 1.9, 95% CI 1.1–3.3) and multiparity (OR 1.4, 95% CI 1.1–1.7).

Conclusions

Women with migraine stop or switch medications during pregnancy. Analgesic use in pregnancy is affected by migraine characteristics and intensity, and also by socio-demographic factors. Clinicians should bear this in mind when giving advice on adequate management of migraine in pregnancy and safe analgesic use.

Electronic supplementary material

The online version of this article (doi:10.1186/s12884-017-1399-0) contains supplementary material, which is available to authorized users.

Preventing and treating medication overuse headache

Medication overuse headache is a secondary headache-a worsening of a pre-existing headache (usually a primary headache) owing to overuse of one or more attack-aborting or pain-relieving medications.

Kappa opioid receptor antagonists: A possible new class of therapeutics for migraine prevention

Background Stress is the most commonly reported migraine trigger. Dynorphin, an endogenous opioid peptide acting preferentially at kappa opioid receptors (KORs), is a key mediator of stress responses. The aim of this study was to use an injury-free rat model of functional cephalic pain with features of migraine and medication overuse headache (MOH) to test the possible preventive benefit of KOR blockade on stress-induced cephalic pain. Methods Following sumatriptan priming to model MOH, rats were hyper-responsive to environmental stress, demonstrating delayed cephalic and extracephalic allodynia and increased levels of CGRP in the jugular blood, consistent with commonly observed clinical outcomes during migraine. Nor-binaltorphimine (nor-BNI), a long-acting KOR antagonist or CYM51317, a novel short-acting KOR antagonist, were given systemically either during sumatriptan priming or immediately before environmental stress challenge. The effects of KOR blockade in the amygdala on stress-induced allodynia was determined by administration of nor-BNI into the right or left central nucleus of the amygdala (CeA). Results KOR blockade prevented both stress-induced allodynia and increased plasma CGRP. Stress increased dynorphin content and phosphorylated KOR in both the left and right CeA in sumatriptan-primed rats. However, KOR blockade only in the right CeA prevented stress-induced cephalic allodynia as well as extracephalic allodynia, measured in either the right or left hindpaws. U69,593, a KOR agonist, given into the right, but not the left, CeA, produced allodynia selectively in sumatriptan-primed rats. Both stress and U69,593-induced allodynia were prevented by right CeA U0126, a mitogen-activated protein kinase inhibitor, presumably acting downstream of KOR. Conclusions Our data reveal a novel lateralized KOR circuit that mediated stress-induced cutaneous allodynia and increased plasma CGRP in an injury-free model of functional cephalic pain with features of migraine and medication overuse headache. Selective, small molecule, orally available, and reversible KOR antagonists are currently in development and may represent a novel class of preventive therapeutics for migraine.

Pediatric Headache: An Overview

Headache represents the most common neurologic disorder in the general population including children and is increasingly being recognized as a major source of morbidity in youth related to missed school days and activities. In this article, we take a holistic approach to the child presenting with headache with a focus on the detailed headache history, physical and neurologic examinations, and diagnostic evaluation of these patients. Clinical presentations and classification schema of multiple primary and secondary headache types in children are discussed using the International Headache Criteria (IHCD-3) as a guide, and a summary provided of the various treatment modalities employed for pediatric headache including lifestyle modifications, behavioral techniques, and abortive and preventive medications.

Neurovascular contributions to migraine: Moving beyond vasodilation

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

Dose-response of spinal manipulation for cervicogenic headache: study protocol for a randomized controlled trial

BACKGROUND

Cervicogenic headache is a prevalent and costly pain condition commonly treated by chiropractors. There is evidence to support the effectiveness for spinal manipulation, but the dose of treatment required to achieve maximal relief remains unknown. The purpose of this paper is to describe the methodology for a randomized controlled trial evaluating the dose-response of spinal manipulation for chronic cervicogenic headache in an adult population.

METHODS/DESIGN

This is a mixed-methods, two-site, prospective, parallel groups, observer-blind, randomized controlled trial conducted at university-affiliated research clinics in the Portland, OR and Minneapolis, MN areas. The primary outcome is patient reported headache frequency. Other outcomes include self-reported headache intensity, disability, quality of life, improvement, neck pain intensity and frequency, satisfaction, medication use, outside care, cervical motion, pain pressure thresholds, health care utilization, health care costs, and lost productivity. Qualitative interviews are also conducted to evaluate patients' expectations of treatment.

DISCUSSION

With growing concerns regarding the costs and side effects of commonly used conventional treatments, greater numbers of headache sufferers are seeking other approaches to care. This is the first full-scale randomized controlled trial assessing the dose-response of spinal manipulation therapy on outcomes for cervicogenic headache. The results of this study will provide important evidence for the management of cervicogenic headache in adults.

TRIAL REGISTRATION

ClinicalTrials.gov (Identifier: NCT01530321).

Management of migraine headaches in a chronic pain patient: A case report

Managing migraines complicated with medication overuse headaches and opioid-induced hyperalgesia can be challenging, especially within the geriatric and chronic pain population. A 65-year-old woman with a degenerative spine condition and chronic migraine headaches, along with other comorbidities, was admitted to the geriatric psychiatry unit for extreme mood swings and paranoia. Prior to admission, she had been taking extended-release morphine sulfate twice daily for more than a month and was unable to determine triggers to her frequent migraine headaches. She had a history of medication overuse and severe migraine episodes within 4 weeks prior to admission. This case report reviews the challenges of treating a geriatric patient with probable chronic migraines in addition to other pain conditions and comorbidities.

Medication overuse headache in Europe and Latin America: general demographic and clinical characteristics, referral pathways and national distribution of painkillers in a descriptive, multinational, multicenter study

BACKGROUND

Medication overuse headache (MOH) is a very disabling and costly disorder due to indirect costs, medication and healthcare utilization. The aim of the study was to describe general demographic and clinical characteristics of MOH, along with the national referral pathways and national painkillers distribution in several European and Latin American (LA) Countries.

METHODS

This descriptive cross-sectional observational study included 669 patients with MOH referred to headache-centers in Europe and LA as a part of the COMOESTAS project. Information about acute medication and healthcare utilization were collected by extensive questionnaires, supplemented with structured patient interviews.

RESULTS

Triptans were overused by 31 % European patients and by 6 % in LA (p < 0.001), whereas ergotamines were overused by 4 % in Europe and 72 % in LA (p < 0.001). Simple analgesics were overused by 54 % in Europe and by 33 % in LA (p < 0.001), while combination-analgesics were more equally overused (24 % in Europe and 29 % in LA). More European patients (57 %) compared with LA patients (27 %) visited general practitioners (p < 0.001), and 83 % of European patients compared to 38 % in LA consulted headache specialists (p < 0.001). A total of 20 % in Europe and 30 % in LA visited emergency rooms (p = 0.007).

CONCLUSION

There are marked variations between LA and Europe in healthcare pathways and in acute medication overuse regarding patients with MOH. This should be considered when planning prevention campaigns against MOH.

Prevalence of primary headache disorders in Fayoum Governorate, Egypt

Background

There is abundance of epidemiological studies of headache in developed and western countries; however, data in developing countries and in Egypt are still lacking. This study aims to detect the prevalence of primary headache disorders in both urban and rural sectors in Fayoum governorate, Egypt.

Methods

A total of 2600 subjects were included using multi-stage stratified systematic random sampling, with respondent rate of 91.3 %. A pre-designed Arabic version, interviewer-administered, pilot tested structured questionnaire was developed according to The International Classification of Headache Disorders, 3rd edition (beta version), and this questionnaire was validated and the strength of agreement in headache diagnosis was good.

Results

The 1-year headache prevalence was 51.4 %, which was more prevalent in urban dwellers. The most common primary headache type was episodic tension type headache (prevalence; 24.5 %), followed by episodic migraine (prevalence; 17.3 %), both types peaked in midlife. Headache disorders were more common in females with exception of cluster headache that showed the expected male dominance. The risk of chronic headache increased more than one fold and half when the participants were females, married, and in those with high education. More than 60 % of our participants did not seek medical advice for their headaches problem; this percentage was higher in rural areas.

Conclusions

Primary headache disorders are common in Egypt; prevalence rate was comparable with western countries with exception of episodic tension headache. Still headache is under-estimated and under-recognized in Egypt and this problem should be targeted by health care providers.

Clinical and Demographical Characteristics of Patients with Medication Overuse Headache in Argentina and Chile: Analysis of the Latin American Section of COMOESTAS Project

BACKGROUND

Data on the characteristics of Medication Overuse Headache (MOH) in Latin American (LA) are scarce. Here we report the demographic and clinical features of the MOH patients from Argentina and Chile enrolled in the multinational COMOESTAS project in the period 2008-2010.

METHODS

The LA population was formed by 240 MOH subjects, 110 from Chile and 130 from Argentina, consecutively attending the local headache centres. In each centre, specifically trained neurologist interviewed and confirmed the diagnosis according to the ICHD-II criteria. A detailed history was collected on an electronic patient record form.

RESULTS

The mean patient age was 38.6 years, with a female/male ratio of 8:2. The mean time since onset of the primary headache was 21 years, whereas duration of MOH was 3.9 years. The primary headache was migraine without aura in 77.5 % and migraine with aura in 18.8 %. Forty two % of the patients self-reported emotional stress associated with the chronification of headache; 43.8 % reported insomnia. The most overused medications were acute drug combinations containing ergotamine (70 %), NSAIDs (33.8 %) and triptans (5.4 %).

CONCLUSION

Though little described, MOH is present also in LA, where it affects mostly women, in the most active decades of life. Some differences emerge as regards the demographic and clinical characteristics of MOH in this population as compared to Europe or Northern America. What seems more worrying about MOH in Argentina and Chile is that most patients overuse ergotamine, a drug that may cause serious adverse events when used chronically. These findings once more underscore the importance of properly diagnose and treat MOH.

Prescription pain medications and chronic headache in Denmark: implications for preventing medication overuse

PURPOSE

The aim of the present paper is to study which prescription pain medications are most commonly dispensed to people with chronic headache (CH), particularly those with medication-overuse headache (MOH).

METHODS

This cross-sectional study analysed prescription pain medications dispensed within 1 year to 68,518 respondents of a national health survey. Participants with headache ≥ 15 days per month for 3 months were classified as having CH. Those with CH and over-the-counter analgesic use ≥ 15 days per month or purchase of ≥ 20 or ≥ 30 defined daily doses (DDDs) of prescription pain medication per month (depending on the drug) were classified as having MOH. Associations between CH and other chronic pain conditions were analysed by logistic regression.

RESULTS

Among those with CH (adjusted prevalence 3.3%, CI 3.2-3.5%), pain medications most commonly dispensed were paracetamol, tramadol, ibuprofen and codeine. CH was associated with osteoarthritis, back pain, and rheumatoid arthritis. Among those with MOH, 32.4% were dispensed an opioid at least once within 1 year. Only 5.1% of people with CH were dispensed triptans.

CONCLUSIONS

High prevalence of opioid use among people with CH may be due to inappropriate headache treatment or development of MOH among those treated for other pain conditions. While there were cases of triptan overuse, triptans remain underutilized among those with CH, suggesting that migraine may be under-recognized and inappropriately treated, leading to overuse of other medications. Education of physicians on appropriate headache management is essential for MOH prevention. There is a need to increase universal awareness about MOH as an adverse effect of long-term analgesic use.

Meningeal afferent signaling and the pathophysiology of migraine

Migraine is the most common neurological disorder. Attacks are complex and consist of multiple phases but are most commonly characterized by intense, unilateral, throbbing headache. The pathophysiology contributing to migraine is poorly understood and the disorder is not well managed with currently available therapeutics, often rendering patients disabled during attacks. The mechanisms most likely to contribute to the pain phase of migraine require activation of trigeminal afferent signaling from the cranial meninges and subsequent relay of nociceptive information into the central nervous system in a region of the dorsal brainstem known as the trigeminal nucleus caudalis. Events leading to activation of meningeal afferents are unclear, but nerve endings within this tissue are mechanosensitive and also express a variety of ion channels including acid-sensing ion channels and transient receptor-potential channels. These properties may provide clues into the pathophysiology of migraine by suggesting that decreased extracellular pH and environmental irritant exposure in the meninges contributes to headache. Neuroplasticity is also likely to play a role in migraine given that attacks are triggered by routine events that are typically nonnoxious in healthy patients and clear evidence of sensitization occurs during an attack. Where and how plasticity develops is also not clear but may include events directly on the afferents and/or within the TNC. Among the mediators potentially contributing to plasticity, calcitonin gene-related peptide has received the most attention within the migraine field but other mechanisms may also contribute. Ultimately, greater understanding of the molecules and mechanisms contributing to migraine will undoubtedly lead to better therapeutics and relief for the large number of patients across the globe who suffer from this highly disabling neurological disorder.

Neuromodulation in migraine: state of the art and perspectives

Migraine is a highly prevalent and disabling disease. The drugs prescribed for migraine prophylaxis can have intolerable side effects or can be ineffective. Neuromodulation techniques are increasingly used in neurology. Transcutaneous supraorbital nerve stimulation is effective in episodic migraine prevention, whereas vagus nerve stimulation provides interesting results in acute migraine therapy. Transcranial stimulation techniques gave variable, and sometimes contradictory, results. The visual cortex is the target of choice in migraine: studies in migraine prevention and aura acute treatment are encouraging. These noninvasive therapies appear safe with a low rate of side effects. Available studies of invasive occipital nerve stimulation in chronic migraine gave modest results; but invasive occipital nerve stimulation offers a new hope to highly disabled patients who failed to respond to any other treatment. In the future, neuromodulation will probably take an increasing place in migraine treatment, as add-on therapy or alternative to medications, especially because of its attractive safety profile.

Long term headache duration is a factor predicting nonresponse to detoxification and advice in medication overuse headache

Background

Medication overuse headache (MOH) is a very heterogeneous disorder for which a recommended treatment is not yet available. The purpose of this study was to investigate any possible roles of demographic and clinical characteristics of MOH patients that might predict a response to detoxification and advice with or without preventive treatment.

Findings

This ancillary study is part of the Sodium vAlproate in the treatment of Medication Overuse HeadAche (SAMOHA) study that randomized 88 MOH patients for 3-month treatment period with sodium valproate (VPA) (800 mg/day) or placebo after a 6-day outpatient detoxification regimen. Demographic and clinical characteristics obtained on patients from both study arms were analyzed to point out an association with the response to the treatment. While for patients from VPA arm no significant results were obtained, comparing responders to non-responders to detoxification and advice to withdraw from MOH, a significant difference in headache duration was observed. Specifically, the efficacy of such treatment resulted ineffective in headache lasting longer than 30 years.

Conclusions

Our findings suggest that the benefit from detoxification and advice can be excluded in MOH of long duration. Therefore, a preventive treatment is suggested particularly for these patients.