Chronic migraine and medication overuse headache: clarifying the current International Headache Society classification criteria

The Evolution of Medication Overuse Headache: History, Pathophysiology and Clinical Update

Medication overuse headache (MOH), the development or worsening of chronic headache resulting from frequent and excessive intake of medications used for acute treatment of headache, is a common secondary headache disorder and is associated with significant personal and societal burdens. The plausible physiologic mechanism is that chronic exposure to acute care migraine treatment leads to suppression of endogenous antinociceptive systems, consequently facilitating the trigeminal nociceptive process via up-regulation of the calcitonin gene-related peptide (CGRP) system. Recognizing and preventing its development is an integral aspect of migraine management, as medication overuse is a modifiable risk factor in the progression from episodic to chronic migraine. Over the years, MOH has been difficult to treat and has generated much controversy. Ongoing debates exist over the diagnostic criteria and treatment strategies, particularly regarding the roles of formal detoxification and preventive treatment. The arrival of the anti-CGRP monoclonal antibodies has also challenged our views of MOH and its treatment. This review outlines the evolution of MOH diagnostic criteria, presents the current understanding of MOH pathogenesis and discusses the debates over its development and treatment. Data on the efficacy of anti-CGRP monoclonal antibodies in the setting of medication overuse is also presented. These results indicate that patients with medication overuse, who are treated with these new medications, may not need to be detoxified in order to treat MOH. In light of these developments, it is likely that in the future MOH will be more readily diagnosed and treatment will result in better outcomes.

Chronic Pain in Children and Adolescents: Diagnosis and Treatment of Primary Pain Disorders in Head, Abdomen, Muscles and Joints

Primary pain disorders (formerly "functional pain syndromes") are common, under-diagnosed and under-treated in children and teenagers. This manuscript reviews key aspects which support understanding the development of pediatric chronic pain, points to the current pediatric chronic pain terminology, addresses effective treatment strategies, and discusses the evidence-based use of pharmacology. Common symptoms of an underlying pain vulnerability present in the three most common chronic pain disorders in pediatrics: primary headaches, centrally mediated abdominal pain syndromes, and/or chronic/recurrent musculoskeletal and joint pain. A significant number of children with repeated acute nociceptive pain episodes develop chronic pain in addition to or as a result of their underlying medical condition "chronic-on-acute pain." We provide description of the structure and process of our interdisciplinary, rehabilitative pain clinic in Minneapolis, Minnesota, USA with accompanying data in the treatment of chronic pain symptoms that persist beyond the expected time of healing. An interdisciplinary approach combining (1) rehabilitation; (2) integrative medicine/active mind-body techniques; (3) psychology; and (4) normalizing daily school attendance, sports, social life and sleep will be presented. As a result of restored function, pain improves and commonly resolves. Opioids are not indicated for primary pain disorders, and other medications, with few exceptions, are usually not first-line therapy.

Chronic Daily Headache in Children and Adolescents: A Multi-Faceted Syndrome

Chronic daily headache (CDH) is a multi-faceted, often complex pain syndrome in children and adolescents. Chronic daily headache may be primary or secondary. Chronic migraine and chronic tension-type are the most frequent subtypes. Chronic daily headache is co-morbid with adverse life events, anxiety and depressive disorders, possibly with other psychiatric disorders, other pain syndromes and sleep disorders; these conditions contribute to initiating and maintaining CDH. Hence, early management of episodic headache and treatment of associated conditions are crucial to prevention. There is evidence for the benefit of psychological therapies, principally relaxation and cognitive behavioral, and promising information on acupuncture for CDH. Data on drug treatment are based primarily on open label studies. The controversies surrounding CDH are discussed and proposals for improvement presented. The multifaceted nature of CDH makes it a good candidate for a multi-axial classification system. Such an approach should facilitate biopsychosocial management and enhance consistency in clinical research.

Chronic Daily Headache and Medication Overuse Headache in First-Visit Headache Patients in Korea: A Multicenter Clinic-Based Study

Background and Purpose

Chronic daily headache (CDH) is defined as a headache disorder in which headaches occur on a daily or near-daily basis (at least 15 days/month) for more than 3 months. Chronic migraine (CM) and medication overuse headache (MOH) are very disabling headaches that remain underdiagnosed. The aim of this study was to establish the frequency of CDH and its various subtypes, and examine the associations with MOH among first-visit headache patients presenting at neurology outpatient clinics in Korea.

Methods

Eleven neurologists enrolled first-visit patients with complaints of headaches into outpatient clinics for further assessment. Headache disorders were classified according to the International Classification of Headache Disorder (third edition beta version) by each investigator.

Results

Primary CDH was present in 248 (15.2%) of the 1,627 included patients, comprising CM (143, 8.8%), chronic tension-type headache (CTTH) (98, 6%), and definite new daily persistent headache (NDPH) (7, 0.4%). MOH was associated with headache in 81 patients (5%). The association with MOH was stronger among CM patients (34.5%) than patients with CTTH (13.3%) or NDPH (14.3%) (p=0.001). The frequency of CDH did not differ between secondary and tertiary referral hospitals.

Conclusions

The frequencies of CDH and MOH diagnoses were 15.2% and 5%, respectively in first-visit headache patients presented at secondary or tertiary referral hospitals in Korea. CM was the most common subtype of CDH and was most frequently associated with MOH.

Medication-overuse headache: a review

Medication-overuse headache (MOH) is a worldwide health problem with a prevalence of 1%–2%. It is a severe form of headache where the patients often have a long history of headache and of unsuccessful treatments. MOH is characterized by chronic headache and overuse of different headache medications. Through the years, withdrawal of the overused medication has been recognized as the treatment of choice. However, currently, there is no clear consensus regarding the optimal strategy for management of MOH. Treatment approaches are based on expert opinion rather than scientific evidence. This review focuses on aspects of epidemiology, diagnosis, pathogenesis, prevention, and treatment of MOH. We suggest that information and education about the risk of MOH is important since the condition is preventable. Most patients experience reduction of headache days and intensity after successful treatment. The first step in the treatment of MOH should be carried out in primary care and focus primarily on withdrawal, leaving prophylactic medication to those who do not manage primary detoxification. For most patients, a general practitioner can perform the follow-up after detoxification. More complicated cases should be referred to neurologists and headache clinics. Patients suffering with MOH have much to gain by an earlier treatment-focused approach, since the condition is both preventable and treatable.

Medication-overuse headache: epidemiology, diagnosis and treatment

Medication-overuse headache (MOH) is one of the most common chronic headache disorders and a public health problem with a worldwide prevalence of 1-2%. It is a condition characterized by chronic headache and overuse of different headache medications, and withdrawal of the overused medication is recognised as the treatment of choice. However, the strategy for achieving withdrawal is, at present, based on expert opinion rather than scientific evidence, partly due to the lack of randomised controlled studies. This narrative review investigates different aspects of epidemiology, diagnosis, risk factors and pathogenesis as well as management for MOH. We suggest that the first step in the treatment of MOH should be carried out in general practice and should focus primarily on detoxification. For most patients, both prevention and follow up after detoxification can also be performed in general practice, thus freeing resources for referral of more complicated cases to headache clinics and neurologists. These suffering patients have much to gain by an earlier treatment-focused approach lower down on the treatment ladder.

Definitions of medication-overuse headache in population-based studies and their implications on prevalence estimates: a systematic review

BACKGROUND

Case definitions of medication-overuse headache (MOH) in population-based research have changed over time. This study aims to review MOH prevalence reports with respect to these changes, and to propose a practical case definition for future studies based on the ICHD-3 beta.

METHODS

A systematic literature search was conducted to identify MOH prevalence studies. Findings were summarized according to diagnostic criteria.

RESULTS

Twenty-seven studies were included. The commonly used case definition for MOH was headache ≥15 days/month with concurrent medication overuse ≥3 months. There were varying definitions for what was considered as overuse. Studies that all used ICHD-2 criteria showed a wide range of prevalence among adults: 0.5%-7.2%.

CONCLUSIONS

There are limits to comparing prevalence of MOH across studies and over time. The wide range of reported prevalence might not only be due to changing criteria, but also the diversity of countries now publishing data. The criterion "headache occurring on ≥15 days per month" with concurrent medication overuse can be applied in population-based studies. However, the new requirement that a respondent must have "a preexisting headache disorder" has not been previously validated. Exclusion of other headache diagnoses by expert evaluation and ancillary examinations is not feasible in large population-based studies.

Laminar infarcts in clinical routine: a prospective analysis in standard stroke unit patients

The present study aimed to investigate prospectively the frequency of laminar infarcts (LI) within a standard stroke unit population. Laminar infarcts follow neuroanatomical borders rather than the vascular architecture. The LI are rarely noticed in clinical routine because they are typically not detected by computed tomography. As there is a lack of systemic studies about this specific infarct pattern, little is known about their frequency, clinical characteristics or pathophysiological mechanisms. Consecutive acute ischemic stroke unit patients were prospectively enrolled during a 12 month period. The LI were defined as ischemic lesions following the gyral anatomy of the cerebral cortex. The clinical assessment included a standardized questionnaire, clinical syndromes and standard diagnostic results. There were 491 consecutive ischemic stroke patients enrolled (243 female, mean age 75 ± 12 years). The MRI revealed no laminar lesion crossing vascular territories and 28 patients with LI non-crossing vascular territories (7 %). According to the TOAST classification, 61 % of LI were classified as stroke of undetermined etiology (TOAST V) including 46 % with completed evaluation (TOAST Vb). In contrast to these findings, only 20 % of the whole study cohort with non-laminar infarcts were classified as TOAST V. The results indicate that LI are rare. In clinical routine, patients with LI require particular attention. Within the TOAST classification, this specific infarct pattern seems to be underrepresented.

Chronic migraine and chronic daily headache in the Asia-Pacific region: a systematic review

BACKGROUND

Data on the prevalence and characteristics of chronic migraine (CM) and chronic daily headache (CDH) in the Asia-Pacific region are limited.

METHODS

We performed a systematic review on this topic, searching for studies published from 1996 to 2012 that reported the prevalence (population-based studies) or frequency (clinic studies) of CM or CDH. We calculated 95% confidence intervals for the prevalence in population studies. Results were qualitatively described.

RESULTS

Seven population studies and 19 hospital clinic studies from Asia were included. The CDH prevalence in population studies was 1.0-3.9% (median 2.9%). Only two studies from Taiwan reported the population prevalence of CM (1.0% and 1.7%). In addition, we derived a prevalence of 0.6% from a Malaysian study. Eleven clinic studies reported a CM frequency of 4.7-82% (median 52%) as a subset of CDH; classification of medication overuse varied. CM was associated with substantial disability.

CONCLUSIONS

The prevalence of CM and CDH in Asia appears lower than the global average, but applying the above prevalence estimates to the Asia-Pacific population would suggest that CM alone affects between 23 and 65 million individuals in the region.

Cortical response to somatosensory stimulation in medication overuse headache patients is influenced by angiotensin converting enzyme (ACE) I/D genetic polymorphism

BACKGROUND

Medication overuse headache (MOH) is a disabling health problem. Convincing evidence attributes a pathophysiologic role to central sensitization. By recording somatosensory evoked potentials (SSEPs) in patients with MOH, we observed increased sensitization and deficient habituation to repetitive sensory stimuli consistent with drug overuse. The renin-angiotensin system in the brain seems to play a relevant role in neural plasticity and dependence behavior. We therefore sought differences in SSEP sensitization and habituation in patients with MOH who underwent angiotensin converting enzyme (ACE) I/D polymorphism analysis.

METHODS

We recorded median-nerve SSEPs (two blocks of 100 sweeps) in 43 patients with MOH. We measured N20-P25 amplitudes, and assessed sensitization using the first block amplitudes, and habituation using amplitude changes between the two sequential blocks. According to their genotype, subjects were divided into three groups: "D/D", "D/I" and "I/I" carriers.

RESULTS

The habituation slope of the two SSEP block amplitudes was significantly increased in the D/D subgroup (n = 16) with respect to that of the I/I subgroup (n = 6), with the D/I subgroup (n = 21) falling in between. In D/D carriers, the habituation slope correlated positively with the duration of the overuse headache, and the first SSEP block amplitudes, a measure of sensitization, increased in strict relationship with the type of overused medication in the MOH patients overall and in the D/D subgroup; this was not so in the D/I and I/I subgroups.

CONCLUSION

In patients with MOH, the homozygote D/D ACE polymorphism influences habituation and sensitization to repeated sensory stimuli in strict relationship with medication overuse. We suggest that angiotensin peptides influence neuronal mechanisms of plasticity by interacting with central monoaminergic synaptic transmission.

Medical and psychological risks and consequences of long-term opioid therapy in women

BACKGROUND

Long-term opioid use has increased substantially over the past decade for U.S. women. Women are more likely than men to have a chronic pain condition, to be treated with opioids, and may receive higher doses. Prescribing trends persist despite limited evidence to support the long-term benefit of this pain treatment approach.

PURPOSE

To review the medical and psychological risks and consequences of long-term opioid therapy in women.

METHOD

Scientific literature containing relevant keywords and content were reviewed.

RESULTS AND CONCLUSIONS

Long-term opioid use exposes women to unique risks, including endocrinopathy, reduced fertility, neonatal risks, as well as greater risk for polypharmacy, cardiac risks, poisoning and unintentional overdose, among other risks. Risks for women appear to vary by age and psychosocial factors may be bidirectionally related to opioid use. Gaps in understanding and priorities for future research are highlighted.

Chronic migraine classification: current knowledge and future perspectives

In the field of so-called chronic daily headache, it is not easy for migraine that worsens progressively until it becomes daily or almost daily to find a precise and universally recognized place within the current international headache classification systems. In line with the 2006 revision of the second edition of the International Classification of Headache Disorders (ICHD-2R), the current prevailing opinion is that this headache type should be named chronic migraine (CM) and be characterized by the presence of at least 15 days of headache per month for at least 3 consecutive months, with headache having the same clinical features of migraine without aura for at least 8 of those 15 days. Based on much evidence, though, a CM with the above characteristics appears to be a heterogeneous entity and the obvious risk is that its definition may be extended to include a variety of different clinical entities. A proposal is advanced to consider CM a subtype of migraine without aura that is characterized by a high frequency of attacks (10-20 days of headache per month for at least 3 months) and is distinct from transformed migraine (TM), which in turn should be included in the classification as a complication of migraine. Therefore, CM should be removed from its current coding position in the ICHD-2 and be replaced by TM, which has more restrictive diagnostic criteria (at least 20 days of headache per month for at least 1 year, with no more than 5 consecutive days free of symptoms; same clinical features of migraine without aura for at least 10 of those 20 days).

Quality of life impairment, disability and economic burden associated with chronic daily headache, focusing on chronic migraine with or without medication overuse: a systematic review

OBJECTIVE

To evaluate the evidence for quality of life (QoL) impairment, disability, healthcare resource use and economic burden associated with chronic daily headache (CDH), focusing on chronic migraine (CM) with or without medication overuse.

METHODS

A systematic review and qualitative synthesis of studies of patients/subjects with CDH that included CM, occurring on at least 15 days per month.

MAIN FINDINGS

Thirty-four studies were included for review (25 studies of patients and nine of subjects from the general population). CDH and CDH with medication overuse headache (MOH) were consistently associated with a lower QoL compared to control or episodic headache (EH) and CDH without MOH. CDH was consistently associated with greater disability and productivity loss, more consultations, more or longer hospitalizations and higher direct costs than EH. Data were not amenable to statistical pooling.

PRINCIPAL CONCLUSIONS

The findings of this review underline the detriment to QoL and the disabling nature of CDH, and in particular CM and CDH with MOH, and negative impact on workplace productivity compared to other types of headache.

Combined analgesics in (headache) pain therapy: shotgun approach or precise multi-target therapeutics?

BACKGROUND

Pain in general and headache in particular are characterized by a change in activity in brain areas involved in pain processing. The therapeutic challenge is to identify drugs with molecular targets that restore the healthy state, resulting in meaningful pain relief or even freedom from pain. Different aspects of pain perception, i.e. sensory and affective components, also explain why there is not just one single target structure for therapeutic approaches to pain. A network of brain areas ("pain matrix") are involved in pain perception and pain control. This diversification of the pain system explains why a wide range of molecularly different substances can be used in the treatment of different pain states and why in recent years more and more studies have described a superior efficacy of a precise multi-target combination therapy compared to therapy with monotherapeutics.

DISCUSSION

In this article, we discuss the available literature on the effects of several fixed-dose combinations in the treatment of headaches and discuss the evidence in support of the role of combination therapy in the pharmacotherapy of pain, particularly of headaches. The scientific rationale behind multi-target combinations is the therapeutic benefit that could not be achieved by the individual constituents and that the single substances of the combinations act together additively or even multiplicatively and cooperate to achieve a completeness of the desired therapeutic effect.As an example the fixed-dose combination of acetylsalicylic acid (ASA), paracetamol (acetaminophen) and caffeine is reviewed in detail. The major advantage of using such a fixed combination is that the active ingredients act on different but distinct molecular targets and thus are able to act on more signalling cascades involved in pain than most single analgesics without adding more side effects to the therapy.

SUMMARY

Multitarget therapeutics like combined analgesics broaden the array of therapeutic options, enable the completeness of the therapeutic effect, and allow doctors (and, in self-medication with OTC medications, the patients themselves) to customize treatment to the patient's specific needs. There is substantial clinical evidence that such a multi-component therapy is more effective than mono-component therapies.

Chronic daily headache in a patient with nasopharyngeal carcinoma

Chronic daily headache (CDH) among nasopharyngeal carcinoma (NPC) patients is a multidisciplinary challenge. Although imaging studies are recommended to identify skull-base invasion, intracranial metastasis or skull-base osteoradionecrosis, a headache diary is also a practical approach. A 42-year-old woman had been bothered with CDH since she was diagnosed with T3N1M0 stage III NPC 2 years earlier. Although the imaging studies did not show any abnormality, the attending doctor informed her that there remained the possibility of an intracranial or skull-base lesion. She was regularly taking painkillers. Eventually, when her headache diary was examined, the diagnosis of chronic migraine superimposed on medication overuse headache was made according to the ICHD-IIR. The CDH abated after 1 week of outpatient detoxification. The following half year was uneventful. In reporting this case, we suggest that it would be of interest to a number of disciplines including otorhinolaryngologists, oncologists and radio-oncologists. By avoiding medication overuse in similar patients, we hope to improve the quality of life of these individuals.

Epidemiological classification and social impact of chronic headache

The current prevalent opinion is that a diagnosis of chronic headache should be established in patients who have had a form of primary headache other than cluster headache on at least 15 days a month for at least 3 months. Chronic headache so defined includes four different subtypes: hemicrania continua and new daily persistent headache--two rare forms currently included in the group "Other primary headaches" of the 2004 International Classification of Headache Disorders, second edition (ICHD-II)--chronic tension-type headache, and chronic migraine. Regarding the latter, which has been better known lately as transformed migraine, the current revised diagnostic criteria establish that migraine must be present on at least 8 of the at least 15 days of headache per month and that there must not be any overuse of symptomatic medication. Chronic headache affects about 3-5% of the general population and results in a variety of negative repercussions both on individuals and on society at large.

Proposal for a new classification of chronic headache

Since the publication of the second edition of the International Classification of Headache Disorders (ICHD-2) in 2004, a fiery debate has been raging about chronic daily headache in general and about chronic migraine and medication overuse headache in particular. Based on a number of considerations and observations on the current state of knowledge, a proposal is advanced that suggests a few changes to ICHD-2, namely: (1) differentiation of migraine without aura at the second-digit level into infrequent, frequent and very frequent, based on frequency of attacks. (2) Inclusion of transformed migraine among the complications of migraine; this entry should be coded to 1.5.1 replacing chronic migraine and the only diagnostic criterion that needs to be changed over those already listed in the revised ICHD-2 (ICHD-2R) is its temporal pattern (more than 20 days/month for 1 year or more and never with more than 5 headache-free consecutive days). (3) Differentiation of transformed migraine at the fourth-digit level depending on the presence or absence of symptomatic medication overuse (i.e. use for more than 20 days/month) regardless of whether overuse played any role in the worsening of the headache. (4) Switching of medication overuse headache to the Appendix with other diagnostic criteria to be defined.

The classification of chronic headache: room for further improvement?

In this commentary, the authors briefly discuss their views on some of the limitations in the current terminology and classification of chronic headache. Suggestions for consideration and further debate include the acceptance of chronic daily headache as the umbrella term for this group of headache disorders, a more consistent definition of 'chronic' and the use of a multi-axial classification approach.