Introduction The objective of this review is to provide an evidence-based discussion of different treatment strategies for medication-overuse headache (MOH). Method We searched PubMed for articles discussing the treatment and prognosis of MOH published between 2004 and August 2014. Titles, abstract and articles were reviewed systematically. The level of evidence provided by each study of the included articles was determined according to the American Academy of Neurology Clinical practice guideline manual. We discuss the level of evidence to support the early discontinuation/withdrawal of overused medications, the level of evidence to support the use of preventive treatment, the short- and long-term prognosis, and the outcome according to the class of drug overused in patients diagnosed with MOH. Results The initial search resulted in 1313 articles; 68 articles met our inclusion criteria and were discussed. The level of evidence to support early discontinuation of overused medications alone is low due to the absence of controlled studies. Adding preventive medication to early discontinuation led to a better outcome than early discontinuation alone. For patients with chronic migraine (CM) and medication overuse (MO), there are large randomized control trials supporting the use of onabotulinumtoxinA and topiramate without early discontinuation of overuse; however, the evidence is limited since data were obtained from post hoc analysis. Conclusion Considering current available evidence and the systemic toxicity of overusing acute headache medication, we suggest discontinuation of the overused medication with the addition of preventive medication. Appropriately sized, randomized controlled trials evaluating the safety and long-term efficacy of preventive medication plus early discontinuation of overuse vs preventive medication alone vs early discontinuation of overuse alone are needed.
Accurate Classification of Chronic Migraine via Brain Magnetic Resonance Imaging
Background The International Classification of Headache Disorders provides criteria for the diagnosis and subclassification of migraine. Since there is no objective gold standard by which to test these diagnostic criteria, the criteria are based on the consensus opinion of content experts. Accurate migraine classifiers consisting of brain structural measures could serve as an objective gold standard by which to test and revise diagnostic criteria. The objectives of this study were to utilize magnetic resonance imaging measures of brain structure for constructing classifiers: (1) that accurately identify individuals as having chronic vs episodic migraine vs being a healthy control; and (2) that test the currently used threshold of 15 headache days/month for differentiating chronic migraine from episodic migraine. Methods Study participants underwent magnetic resonance imaging for determination of regional cortical thickness, cortical surface area, and volume. Principal components analysis combined structural measurements into principal components accounting for 85% of variability in brain structure. Models consisting of these principal components were developed to achieve the classification objectives. Tenfold cross validation assessed classification accuracy within each of the 10 runs, with data from 90% of participants randomly selected for classifier development and data from the remaining 10% of participants used to test classification performance. Headache frequency thresholds ranging from 5‐15 headache days/month were evaluated to determine the threshold allowing for the most accurate subclassification of individuals into lower and higher frequency subgroups. Results Participants were 66 migraineurs and 54 healthy controls, 75.8% female, with an average age of 36 +/− 11 years. Average classifier accuracies were: (1) 68% for migraine (episodic + chronic) vs healthy controls; (2) 67.2% for episodic migraine vs healthy controls; (3) 86.3% for chronic migraine vs healthy controls; and (4) 84.2% for chronic migraine vs episodic migraine. The classifiers contained principal components consisting of several structural measures, commonly including the temporal pole, anterior cingulate cortex, superior temporal lobe, entorhinal cortex, medial orbital frontal gyrus, and pars triangularis. A threshold of 15 headache days/month allowed for the most accurate subclassification of migraineurs into lower frequency and higher frequency subgroups. Conclusions Classifiers consisting of cortical surface area, cortical thickness, and regional volumes were highly accurate for determining if individuals have chronic migraine. Furthermore, results provide objective support for the current use of 15 headache days/month as a threshold for dividing migraineurs into lower frequency (ie, episodic migraine) and higher frequency (ie, chronic migraine) subgroups.
Migraine affects white-matter tract integrity: A diffusion-tensor imaging study
Background Specific white-matter tract alterations in migraine remain to be elucidated. Using diffusion tensor imaging (DTI), this study investigated whether the integrity of white-matter tracts that underlie regions of the “pain matrix” is altered in migraine and interrogated whether the number of years lived with migraine modifies fibertract structure. Methods Global probabilistic tractography was used to assess the anterior thalamic radiations, the corticospinal tracts and the inferior longitudinal fasciculi in 23 adults with migraine and 18 healthy controls. Results Migraine patients show greater mean diffusivity (MD) in the left and right anterior thalamic radiations, the left corticospinal tract, and the right inferior longitudinal fasciculus tract. Migraine patients also show greater radial diffusivity (RD) in the left anterior thalamic radiations, the left corticospinal tract as well as the left and right inferior longitudinal fasciculus tracts. No group fractional anisotropy (FA) differences were identified for any tracts. Migraineurs showed a positive correlation between years lived with migraine and MD in the right anterior thalamic radiations ( r = 0.517; p = 0.012) and the left corticospinal tract ( r = 0.468; p = 0.024). Conclusion Results indicate that white-matter integrity is altered in migraine and that longer migraine history is positively correlated with greater alterations in tract integrity.
The Acute Treatment of Migraine in Adults: The
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merican
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eadache
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ociety Evidence Assessment of Migr
The study aims to provide an updated assessment of the evidence for individual pharmacological therapies for acute migraine treatment. Pharmacological therapy is frequently required for acutely treating migraine attacks. The A merican A cademy of N eurology G uidelines published in 2000 summarized the available evidence relating to the efficacy of acute migraine medications. This review, conducted by the members of the G uidelines S ection of the A merican H eadache S ociety, is an updated assessment of evidence for the migraine acute medications. A standardized literature search was performed to identify articles related to acute migraine treatment that were published between 1998 and 2013. The A merican A cademy of N eurology G uidelines D evelopment procedures were followed. Two authors reviewed each abstract resulting from the search and determined whether the full manuscript qualified for review. Two reviewers studied each qualifying full manuscript for its level of evidence. Level A evidence requires at least 2 C lass I studies, and L evel B evidence requires 1 C lass I or 2 C lass II studies. The specific medications – triptans (almotriptan, eletriptan, frovatriptan, naratriptan, rizatriptan, sumatriptan [oral, nasal spray, injectable, transcutaneous patch], zolmitriptan [oral and nasal spray]) and dihydroergotamine (nasal spray, inhaler) are effective ( L evel A ). Ergotamine and other forms of dihydroergotamine are probably effective ( L evel B ). Effective nonspecific medications include acetaminophen, nonsteroidal anti‐inflammatory drugs (aspirin, diclofenac, ibuprofen, and naproxen), opioids (butorphanol nasal spray), sumatriptan/naproxen, and the combination of acetaminophen/aspirin/caffeine ( L evel A ). Ketoprofen, intravenous and intramuscular ketorolac, flurbiprofen, intravenous magnesium (in migraine with aura), and the combination of isometheptene compounds, codeine/acetaminophen and tramadol/acetaminophen are probably effective ( L evel B ). The antiemetics prochlorperazine, droperidol, chlorpromazine, and metoclopramide are probably effective ( L evel B ). There is inadequate evidence for butalbital and butalbital combinations, phenazone, intravenous tramadol, methadone, butorphanol or meperidine injections, intranasal lidocaine, and corticosteroids, including dexamethasone ( L evel C ). Octreotide is probably not effective ( L evel B ). There is inadequate evidence to refute the efficacy of ketorolac nasal spray, intravenous acetaminophen, chlorpromazine injection, and intravenous granisetron ( L evel C ). There are many acute migraine treatments for which evidence supports efficacy. Clinicians must consider medication efficacy, potential side effects, and potential medication‐related adverse events when prescribing acute medications for migraine. Although opioids, such as butorphanol, codeine/acetaminophen, and tramadol/acetaminophen, are probably effective, they are not recommended for regular use.
Low heat pain thresholds in migraineurs between attacks
Background/Objective Between attacks, migraine is associated with hypersensitivities to sensory stimuli. The objective of this study was to investigate hypersensitivity to pain in migraineurs between attacks. Methods Cutaneous heat pain thresholds were measured in 112 migraineurs, migraine free for ≥48 hours, and 75 healthy controls. Pain thresholds at the head and at the arm were compared between migraineurs and controls using two-tailed t-tests. Among migraineurs, correlations between heat pain thresholds and headache frequency, allodynia symptom severity, and time interval until next headache were calculated. Results Migraineurs had lower pain thresholds than controls at the head (43.9℃ ± 3.2℃ vs. 45.1℃ ± 3.0℃, p = 0.015) and arm (43.2℃ ± 3.4℃ vs. 44.8℃ ± 3.3℃, p < 0.001). There were not significant correlations between pain thresholds and headache frequency or allodynia symptom severity. For the 41 migraineurs for whom time to next headache was known, there were positive correlations between time to next headache and pain thresholds at the head ( r = 0.352, p = 0.024) and arm ( r = 0.312, p = 0.047). Conclusions This study provides evidence that migraineurs have low heat pain thresholds between migraine attacks. Mechanisms underlying these lower pain thresholds could also predispose migraineurs to their next migraine attack, a hypothesis supported by finding positive correlations between pain thresholds and time to next migraine attack.
Atypical age-related cortical thinning in episodic migraine
Background Prior studies demonstrate reduced cortical thickness and volume in migraineurs. However, the effect of age on cortical thickness has not been assessed in migraineurs. In this study we investigated whether the process of aging on cortical thickness affects migraineurs differently compared to age-matched healthy controls, i.e. whether aging exacerbates cortical thinning in migraineurs. Methods Cortical thickness was estimated using a general linear model vertex-by-vertex approach for 32 healthy controls (mean age = 35.3 years; SD = 11.6) and 27 episodic migraine patients (mean age = 33.6 years; SD = 12.3). Results were modeled using a main effect analysis to estimate the effect of age on cortical thickness for each group separately, and an age-by-group analysis to estimate differences in age-related cortical thinning between migraine patients and normal controls. Results Although migraineurs and normal controls both have expected age-related thinning in many regions along the cortical mantle, migraineurs have age-related thinning of regions that do not thin in healthy controls, including: bilateral postcentral, right fusiform, and right temporal pole areas. Cortical thinning of these regions is more prominent with advancing age. Conclusion Results suggest that migraine is associated with atypical cortical aging, suggesting that the migraine disease process interacts with aging to affect cortical integrity.
Enhanced pain-induced activity of pain-processing regions in a case-control study of episodic migraine
Objective The objective of this study was to identify brain regions having aberrant pain-induced activation in migraineurs, thereby gaining insight into particular aspects of pain processing that are atypical in migraineurs. Methods Functional magnetic resonance imaging assessed whole brain responses to painful heat in 24 adult episodic migraineurs who were at least 48 hours pain free and 27 healthy controls. Regions differentially activated in migraineurs compared to controls were identified. Activation intensities in these regions were correlated with headache frequency, number of migraine years, and time to next migraine attack. Results Migraineurs had greater pain-induced activation of lentiform nucleus, fusiform gyrus, subthalamic nucleus, hippocampus, middle cingulate cortex, premotor cortex, somatosensory cortex, and dorsolateral prefrontal cortex, and less activation in precentral gyrus and superior temporal gyrus. There were significant correlations between activation strength and headache frequency for middle cingulate ( r = 0.627, p = 0.001), right dorsolateral prefrontal cortex ( r = 0.568, p = 0.004), left fusiform gyrus ( r = 0.487, p = 0.016), left precentral gyrus ( r = 0.415, p = 0.044), and left hippocampus ( r = 0.404, p = 0.050) and with number of migraine years for left fusiform gyrus ( r = 0.425, p = 0.038). There were no significant correlations between activation strength and time to next migraine attack. Conclusions The majority of regions with enhanced pain-induced activation in headache-free migraineurs participate in cognitive aspects of pain perception such as attending to pain and pain memory. Enhanced cognitive pain processing by migraineurs might reflect cerebral hypersensitivity related to high expectations and hypervigilance for pain.
Imploding and Exploding Migraine Headaches: Comparison of Methods to Diagnose Pain Directionality
Background The study aims to compare methods of determining headache directionality (imploding, exploding, and/or ocular headaches) in women with migraine, investigate the concordance between physician assignment and patient self‐assignment of pain directionality, and evaluate whether patients assigned their headaches to the same direction when queried using different methods. Directionality of migraine headache pain (imploding, exploding, or ocular) may reflect differences in the underlying pathogenesis of individual migraine attacks among and within individuals. Emerging evidence suggests that directionality of pain in migraine sufferers may predict response to onabotulinumtoxin A . The best method of determining headache directionality in migraine sufferers has not been systematically explored. Methods We conducted a prospective cross‐sectional survey study of 198 female patients with migraine presenting to a W omen's H ealth C linic. Patients determined the directionality (imploding, exploding, and/or ocular) of their own migraine pain by choosing among 3 pictures graphically representing directionality and also by responding to a written question regarding directionality. Clinicians then classified directionality of migraine pain using structured interviews. Concordance between clinician assignment of directionality and patient self‐assignment was determined with K appa coefficients. Results Subjects were females between the ages of 18 and 77 years (mean 48 years). According to patient selection of representative pictures, 62 (31.6%) had imploding headaches with or without ocular pain, 36 (18.4%) had exploding headaches with or without ocular pain, 78 (39.8%) had ocular pain only, and 20 (10.2%) had imploding and exploding headaches with or without ocular pain. Two subjects did not respond. According to patient responses to a written question, 80 (41.0%) had imploding headaches with or without ocular pain, 53 (27.2%) had exploding headaches with or without ocular pain, 46 (23.6%) had ocular pain only, and 16 (8.2%) had imploding and exploding headaches with or without ocular pain. Three subjects did not respond. For physician assignment, 69 (34.9%) subjects had imploding headaches with or without ocular pain, 89 (45%) had exploding headaches with or without ocular pain, 14 (7.1%) had ocular pain only, and 26 (13.1%) had imploding and exploding headaches with or without ocular pain. The concordance ( K appa coefficient) between physician assignment of headache directionality with patient response to the written question was 0.33 (weak agreement), between physician assignment and patient assignment via selection of representative pictures was 0.35 (weak agreement), and between patient assignment via written question and via selection of representative pictures was 0.35 (weak agreement). Conclusions The assignment of headache directionality varied substantially depending upon the method of determination. The concordance between clinician assignment, patient‐self assignment via answering a written question, and patient self‐assignment via choosing a representative picture was weak. Improved methods of determining pain directionality are needed.
Consensus treatment of medication overuse headache in Latin America and Europe
Background It is generally felt that patient education and patient knowledge regarding triptan use for acute migraine management are important for successful and safe treatment. It is unclear how knowledgeable triptan users are regarding their triptan, how much education occurs when triptans are prescribed, and the impact patient education has on actual patient knowledge regarding triptan use. Objective The primary objective was to compare triptan users' self‐perceived knowledge and actual knowledge about triptans in patients who report having received triptan education vs patients who report not having received triptan education. Methods This was a multicenter prospective observational study of 207 migraine patients who were using triptans for abortive therapy and who were being evaluated as new patients at academic headache specialty clinics in the U nited S tates. Patients completed standardized questionnaires regarding their self‐perceived knowledge about triptans, their actual knowledge regarding triptans, and the perceived education about the triptan that they had received at the time of prescription. Results Although greater than 80% of the subjects reported receiving education about when to take the triptan and the number of doses they could take for headache, only 71.5% reported receiving education about triptan side effects, 64% for the number of triptan doses they could take each week/month, 64% for taking other medications with the triptan, and 49% for medical contraindications to triptan use. Compared with subjects who did not recall receiving education about when to take their triptan, subjects who recalled such education had a statistically significant greater actual knowledge for taking the triptan immediately after a headache begins (91% vs 77%, P = .049; confidence interval [ CI ]: 0.00–0.33), treating when pain is mild (75% vs 50%, P = .009; CI : 0.04–0.45), understanding that they do not need to fail treatment with over‐the‐counter medications before taking a triptan (74% vs 42%, P = .001; CI : 0.11–0.51), and recognizing that coronary artery disease is a contraindication to triptan use (40% vs 19%, P = .001; CI : 0.09–0.34). Conclusion This study provides evidence that patients who recall having received education at the time of triptan prescribing have greater knowledge regarding optimal triptan use. Triptan users who recalled having received this education had greater recognition of the importance of taking the triptan immediately at the onset of a headache, treating when pain is mild, not needing to fail treatment with over‐the‐counter medications before taking a triptan, and understanding that coronary artery disease is a contraindication to triptan use.