Chronic daily headache with analgesic overuse: Epidemiology and impact on quality of life

From drug-induced headache to medication overuse headache. A short epidemiological review, with a focus on Latin American countries

Medication overuse headache (MOH) is a daily or almost-daily type of headache that results from the chronicization, usually migraine or tension-type headache, as a consequence of the progressive increase of intake of symptomatic drugs. MOH is now the third most frequent type of headache and affects a percentage of 1-1.4% of the general population. The currently available data on the impact of chronic headache associated with analgesic overuse in specialist headache centres confirm, beyond doubt, the existence of a serious health problem. Limited amount of data exists on the burden and impact of MOH in Latin American Countries. In this review, we summarise the reliable information from the literature on the epidemiological impact of MOH.

Medication overuse headache

The term medication overuse headache (MOH) was recently introduced by the International Headache Society to describe daily or nearly daily (chronic) headache that occurs after the regular intake (overuse) of any kind of antiheadache or antimigraine drug. Chronic headache is a growing problem throughout the world. It affects up to 3% to 4% of the general population, and 30% to 50% of such headaches are attributed to overuse of antiheadache drugs. This article reviews the literature on the epidemiology, risk factors, and pathophysiology of MOH. It also summarizes current strategies for treating and preventing headache chronicity.

Headaches in patients with shunts

Headache is one of the most common afflictions suffered by humans. Headache in patients with a shunt triggers a series of events that includes utilization of expensive technologies and often potentially dangerous surgical intervention. The purpose of this study was to determine the incidence of headaches in patients with shunts and, hopefully, the relationship of those headache disorders to the treatment of hydrocephalus. The Hydrocephalus Association maintains a self-reporting database recorded from individuals treated for hydrocephalus and their families. This database was mined to determine the incidence of severe headaches requiring treatment and interfering with normal life in patients who have been treated for hydrocephalus. There were 1,242 responders between the ages of 19 months and 45 years of age. Of these, 1,233 answered the question, "Do you or your family member suffer from (does your child complain of) frequent or chronic headaches?" This subset forms the basis of this study. Three groups were defined by age: children (19 months-12 years), adolescents (13 years-19 years), and young adults (20 years-45 years). Most respondents were initially treated during infancy (before 18 months of age); 84% of children and 69% of both adolescents and young adults were treated very early in life. Severe headaches became a more frequent problem as the age of the population treated for hydrocephalus increased. In terms of frequency and severity of headaches, direct comparisons with epidemiologic studies of normal populations are difficult because of the limitations of data available in the database. However, it is likely that this population has a higher incidence of severe headaches than normal populations. The cost of management of headaches in this population is very high, and the patients are at risk throughout life. Early treatment decisions have a significant effect on later quality of life. Strategies that lead to normalization of cerebrospinal fluid dynamics and life without shunt dependency are justified if they can be shown to improve later quality of life.

Medication overuse headache: awareness, detection and treatment

Episodic migraine is a disabling painful disease that can affect the normal function of daily routine activities such as performance at work and school, and home and social relationships. In addition to the physical disability during migraine, between attacks many patients experience a condition referred to as interictal burden, which can present as pre-event worry about future attacks and can result in the anticipatory use and/or overuse of acute care medications. The overuse of medication can often lead to medication overuse headaches (MOHs) and chronic migraine. Unfortunately, patients, and even some physicians, are often unaware of this phenomenon. Therefore, it is important for knowledgeable physicians to raise awareness and to address the risks of medication overuse with their patients through effective communication. Future management of medication overuse should include detoxification and a comprehensive programme that includes the use of preventive medications such as sodium valproate (divalproex sodium) and topiramate in order to reduce dependency on acute care medication. Also, MOHs may be most effectively managed with the initiation of preventive treatment prior to detoxification, in addition to the decreased use of acute care medication. A long-term treatment plan, including behavioural therapy, migraine preventive medication and appropriate acute care therapy, may be optimal in treating patients with MOHs.

Management of Medication Overuse Headache: 1-Year Randomized Multicentre Open-Label Trial

It is a general belief that patients with medication overuse headache (MOH) need withdrawal of acute headache medication before they respond to prophylactic medication. In this 1-year open-labelled, multicentre study intention-to-treat analyses were performed on 56 patients with MOH. These were randomly assigned to receive prophylactic treatment from the start without detoxification, undergo a standard out-patient detoxification programme without prophylactic treatment from the start, or no specific treatment (5-month follow-up). The primary outcome measure, change in headache days per month, did not differ significantly between groups. However, the prophylaxis group had the greatest decrease in headache days compared with baseline, and also a significantly more pronounced reduction in total headache index (headache days/month x headache intensity x headache hours) at months 3 ( P = 0.003) and 12 ( P = 0.017) compared with the withdrawal group. At month 12, 53% of patients in the prophylaxis group had ≥ 50% reduction in monthly headache days compared with 25% in the withdrawal group ( P = 0.081). Early introduction of preventive treatment without a previous detoxification programme reduced total headache suffering more effectively compared with abrupt withdrawal. (ClinicalTrials.gov number, NCT00159588).

Chronic Daily Headache in Brazil: A Nationwide Population-Based Study

The objectives of this study were to estimate the 1-year prevalence of chronic daily headache (CDH) and the degree of the association of CDH with some sociodemographic characteristics of the adult population of Brazil. This was a cross-sectional, population-based study. We conducted telephone interviews with 3848 people, aged 18-79 years, randomly selected from the 27 States of Brazil. The degree of the association was calculated through prevalence ratios, adjusted with Poisson regression by gender, age and some sociodemographic factors. The estimated 1-year gender- and age-adjusted prevalence of CDH was 6.9±. CDH was 2.4 times more prevalent in women, 1.72 times more in unemployed, 1.63 times more in subjects with high household income and two times greater in those who did not exercise. The overall prevalence of CDH in Brazil is high. CDH is significantly more prevalent in women, the unemployed, subjects with higher income, and in those who do not exercise.

Acute migraine in the Emergency Department: extending European principles of management

The World Health Organization (WHO) placed migraine 19th among all causes of disability (12th in women) measured in years of healthy life lost to disability (YLD). The importance of headache disorders, particularly of the primary forms, is established by their distribution worldwide, their duration (the majority being life-long conditions) and their imposition of both disability and life-style restrictions among large numbers of people. For these reasons, headache disorders should represent a public-health priority. In the Emergency Department (ED), as elsewhere, migraine is often under-diagnosed-and under-treated when it is diagnosed. The result is likely to be failure of treatment. Particular attention to diagnosis is needed in ED patients with acute headache, since there is a higher probability of secondary headache due to underlying pathologies. According to European principles of management, acute migraine treatment generally is stepwise. Of the two main steps, the first relies on symptomatic medication, preferably NSAIDs with or without antiemetics. The second step uses specific therapies, usually triptans. Modifications to routine practice are appropriate in the ED. Parenteral administration of symptomatic therapies is a preferred first choice, whilst immediate resort to triptans may be appropriate, and achieve better outcomes, in patients with severe headache and diagnostic confirmation of migraine.

Involvement of Corticotrophin-Releasing Factor and Orexin-A in Chronic Migraine and Medication-Overuse Headache: Findings From Cerebrospinal Fluid

The study set out to investigate the role of corticotrophin-releasing factor (CRF) and orexin-A in chronic migraine (CM) and medication-overuse headache (MOH). Twenty-seven patients affected by CM and 30 with MOH were enrolled. Control CSF specimens were obtained from 20 age-matched subjects who underwent lumbar puncture for diagnostic purposes, and in all of them CSF and blood tests excluded central nervous system or systemic diseases. Orexin-A and CRF were determined by radioimmunoassay methods. Significantly higher levels of orexin-A and CRF were found in the CSF of MOH and to a lesser extent in patients with CM compared with control subjects (orexin-A: P < 0.001 and P < 0.02; CRF: P < 0.002 and P < 0.0003). A significant positive correlation was also found between CSF orexin-A values and those of CRF ( R = 0.71; P < 0.0008), monthly drug intake group ( R = 0.39; P < 0.03) and scores of a self-completion 10-item instrument to measure dependence upon a variety of substances, the Leeds Dependence Questionnaire (LDQ) in the MOH group ( R = 0.68; P < 0.0003). The significantly higher orexin-A levels found in CM and MOH can be interpreted as a compensatory response to chronic head pain or, alternatively, as an expression of hypothalamic response to stress due to chronic pain. A potential role for orexin-A in driving drug seeking in MOH patients through activation of stress pathways in the brain can also be hypothesized.

Prevalence of secondary chronic headaches in a population-based sample of 30-44-year-old persons. The Akershus study of chronic headache

We studied secondary chronic headaches (> or = 15 days/month for at least 3 months) in a random sample of 30 000 persons aged 30-44 years. They received a mailed questionnaire. Those with self-reported chronic headache within the last month and/or year were invited to an interview and examination by a neurological resident. The criteria of the International Classification of Headache Disorders (ICHD-II) were applied. The questionnaire response rate was 71%, and the participation rate of the interview was 74%. Of the 633 participants, 298 had a secondary chronic headache. The 1-year prevalence of secondary chronic headache was 2.14%, i.e. chronic posttraumatic headache 0.21%, chronic headache attributed to whiplash injury 0.17%, post-craniotomy headache 0.02%, medication-overuse headache (MOH) 1.72%, cervicogenic headache 0.17%, headache attributed to chronic rhinosinusitis 0.33% and miscellaneous headaches 0.04%. The majority of those with ICHD-II-defined secondary chronic headache had MOH, while about one-third had other secondary headaches often in combination with MOH.

Impact of headache in Europe: a review for the Eurolight project

A recent health economic survey in Europe has suggested that migraine is the costliest among the neurological disorders. According to many studies, migraine and other disorders lead to widespread suffering, reduction of quality of life, and marked impairment of participation, both in work and social activities. The present literature survey was made in order to summarize what is known on the subject, as a preparation for a EU-supported study to assess the impact in several EU countries with similar methodology and the same research instrument. Previous studies have yielded relatively reliable data only for migraine, whereas the impact of tension-type headache is virtually unknown or only very incompletely known for most dimensions of headache impact. Some data do suggest, however, that this headache may be as important from a health economic and a public health perspective as migraine. In future studies it is important to get population-based data from various countries relevant for estimation of indirect (mostly absenteeism from work and reduced working efficiency when having headache) and direct costs (related to medication, consultations, investigations and hospitalisations). Also, the impact on ability to get education and participate in the workforce is very relevant, as is the impact on love life and family planning. The quality of life of headache patients should be measured by validated instruments. To get a complete picture, one should also ask about the effect on the life of partners and children, and on the possible impact even when headache-free (e.g. fear of the next attack).

Prevalence of primary chronic headache in a population-based sample of 30- to 44-year-old persons. The Akershus study of chronic headache

BACKGROUND

Prevalence data on primary chronic headache in the general population based on clinical interviews by physicians are lacking.

METHODS

In a cross-sectional epidemiological survey, a random sample of 30,000 persons from Akershus County, aged 30-44 years, were sent a postal questionnaire. Those with self-reported chronic headache within the last month and/or year were invited to a semi-structured diagnostic interview and a physical and neurological examination conducted by 2 neurological residents with experience in headache diagnostics. The diagnoses were made according to the International Classification of Headache Disorders, 2nd edition, 2004, and relevant revisions.

RESULTS

The questionnaire response rate was 71%, and the participation rate of the interview was 74%. The 1-year prevalence of primary chronic headache was 2.9%. Chronic tension-type headache (CTTH) and probable chronic tension-type headache (pCTTH) had 1-year prevalences of 1.6 and 1.2%, respectively. The prevalences of other primary chronic headaches were: chronic migraine (CM) 0.01%, probable CM 0.09% and other subtypes 0.04%. Co-occurrence of migraine was frequent, as 42% with CTTH and 55% with pCTTH had migraine.

CONCLUSION

Primary chronic headache is prevalent in the general population. The majority has CTTH or pCTTH, while CM and other primary chronic headaches are rare.

Medication-overuse headache: where are we now?

PURPOSE OF REVIEW

Many important studies on medication-overuse headache have been published in the last year. Some of them investigated the pathophysiology of headache chronicity, others focused on evaluation of risk factors. The International Headache Society revised the classification criteria. We provide a summary of the new findings and concepts.

RECENT FINDINGS

Medication-overuse headache was previously defined by the International Headache Society as a chronic headache which occurs following overuse of headache drugs and improves after withdrawal. Hence, the improvement of headache after withdrawal was mandatory for diagnosis. The new appendix criteria appeared last year and established a broader concept of medication-overuse headache no longer requiring improvement after discontinuation of medication overuse. Several large population-based longitudinal studies clearly demonstrated that overuse of any kind of acute headache medication is the main risk factor leading to development of chronic headache. Imaging studies provided new important insights into the pathophysiology of headache chronicity. New treatment strategies have been suggested.

SUMMARY

Recent data provide better insight into pathophysiology of medication-overuse headache. Epidemiological studies clearly demonstrate the necessity of establishing a predictive model for early recognition of patients at high risk to intervene early and avoid development of chronic headache.

The global burden of headache: a documentation of headache prevalence and disability worldwide

This study, which is a part of the initiative 'Lifting The Burden: The Global Campaign to Reduce the Burden of Headache Worldwide', assesses and presents all existing evidence of the world prevalence and burden of headache disorders. Population-based studies applying International Headache Society criteria for migraine and tension-type headache, and also studies on headache in general and 'chronic daily headache', have been included. Globally, the percentages of the adult population with an active headache disorder are 46% for headache in general, 11% for migraine, 42% for tension-type headache and 3% for chronic daily headache. Our calculations indicate that the disability attributable to tension-type headache is larger worldwide than that due to migraine. On the World Health Organization's ranking of causes of disability, this would bring headache disorders into the 10 most disabling conditions for the two genders, and into the five most disabling for women.

Botulinum toxin type A for migraine prophylaxis in the Japanese population: an open-label prospective trial

OBJECTIVE

To evaluate the efficacy and tolerability of Botulinum Toxin Type A (BoNT-A) for migraine prophylaxis.

METHODS

Nineteen Japanese adult patients (50 +/- 10 years old), who met the International Classification of Headache Disorders 2nd Edition (ICHD II) criteria for migraine and had five or more migraine attacks a month, were enrolled in this open-label prospective study. A total of 50 units of BoNT-A were injected in 19-fixed sites of the muscles including procerus, corrugator, frontalis, temporalis and occipitalis. All participants were advised to stop taking preventive medicine from one month before and three months after BoNT-A injection. Migraine disability assessment (MIDAS), migraine questionnaire and headache diary were used for the evaluation of efficacy. Seven patients received repeated injection combined with prophylactic medication.

RESULT

We excluded five patients from the analysis because four patients had medication overuse headache and one continued preventive medicine. Mean MIDAS score decreased significantly two months after the injection. Thirteen of 14 patients stated subjective improvement after the injection on the migraine questionnaire. The amount of analgesics consumption or headache frequency did not change after injection, but the frequency of severe migraine attacks decreased significantly. No serious adverse event was reported. Repeated injections also showed significant reduction in MIDAS score three months after the second and third injections.

CONCLUSION

BoNT-A injection was an effective and safe treatment for migraine prophylaxis among the Japanese population. A randomized placebo control trial is necessary to confirm its efficacy.

Practical considerations for the treatment of elderly patients with migraine

Treatment of migraine presents special problems in the elderly. Co-morbid diseases may prohibit the use of some medications. Moreover, even when these contraindications do not exist, older patients are more likely than younger ones to develop adverse events. Managing older migraine patients, therefore, necessitates particular caution, including taking into account possible pharmacological interactions associated with the greater use of drugs for concomitant diseases in the elderly. Paracetamol (acetaminophen) is the safest drug for symptomatic treatment of migraine in the elderly. Use of selective serotonin 5-HT(1B/1D) receptor agonists ('triptans') is not recommended, even in the absence of cardiovascular or cerebrovascular risk, and NSAID use should be limited because of potential gastrointestinal adverse effects. Prophylactic treatments include antidepressants, beta-adrenoceptor antagonists, calcium channel antagonists and antiepileptics. Selection of a drug from one of these classes should be dictated by the patient's co-morbidities. Beta-adrenoceptor antagonists are appropriate in patients with hypertension but are contraindicated in those with chronic obstructive pulmonary disease, diabetes mellitus, heart failure and peripheral vascular disease. Use of antidepressants in low doses is, in general, well tolerated by elderly people and as effective, overall, as in young adults. This approach is preferred in patients with concomitant mood disorders. However, prostatism, glaucoma and heart disease make the use of tricyclic antidepressants more difficult. Fewer efficacy data in the elderly are available for selective serotonin reuptake inhibitors, which can be tried in particular cases because of their good tolerability profile. Calcium channel antagonists are contraindicated in patients with hypotension, heart failure, atrioventricular block, Parkinson's disease or depression (flunarizine), and in those taking beta-adrenoceptor antagonists and monoamine oxidase inhibitors (verapamil). Antiepileptic drug use should be limited to migraine with high frequency of attacks and refractoriness to other treatments. Promising additional strategies include ACE inhibitors and angiotensin II type 1 receptor antagonists because of their effectiveness and good tolerability in patients with migraine, particularly in those with hypertension. Because of its favourable compliance and safety profile, botulinum toxin type A can be considered an alternative treatment in elderly migraine patients who have not responded to other currently available migraine prophylactic agents. Pharmacological treatment of migraine poses special problems in regard to both symptomatic and prophylactic treatment. Contraindications to triptan use, adverse effects of NSAIDs, and unwanted reactions to some antiemetics reduce the list of drugs available for the treatment of migraine attacks in elderly patients. The choice of prophylactic treatment (beta-adrenoceptor antagonists, calcium channel antagonists, antiepileptics, and more recently, some antihypertensive drugs) is influenced by co-morbidities and should be directed at those drugs that are believed to have fewer adverse effects and a better safety profile. Unfortunately, for most of these drugs, efficacy studies are lacking in the elderly.

Characteristics and Treatment of Headache After Traumatic Brain Injury

Headache is one of the most common complaints in patients with traumatic brain injury. By definition, headache that develops within 1 wk after head trauma (or within 1 wk after regaining consciousness) is referred to as posttraumatic headache (PTH). Although most PTH resolves within 6-12 mos after injury, approximately 18-33% of PTH persists beyond 1 yr. We performed a systematic literature review on this topic and found that many patients with PTH had clinical presentations very similar to tension-type headache (37% of all PTH) and migraine (29% of all PTH). Although there is no universally accepted protocol for treating PTH, many clinicians treat PTH as if they were managing primary headache. As a result of the heterogeneity in the terminology and paucity in prospective, well-controlled studies in this field, there is a definite need for conducting double-blind, placebo-controlled treatment trials in patients with PTH.

Comparison of Short Form-36 and Migraine Disability Assessment Questionnaire in Patients With Migraine

BACKGROUND

The Short Form-36 (SF-36) and Migraine Disability Assessment (MIDAS) questionnaires are two of the most commonly used tools to measure outcomes in people suffering from headaches. Nevertheless, little is known about their interrelationship in patients with headache.

OBJECTIVES

The aim of this study was to investigate the interrelationship between SF-36 and MIDAS questionnaires in patients with migraine.

METHODS

We enrolled 231 patients with migraine (male/female: 43/188, mean age 35.3+/-8.1) who visited our headache clinic. They completed the SF-36, MIDAS, and a headache intake form.

RESULTS

The correlation coefficients between the MIDAS score and 8 domains of the SF-36 ranged from -0.30 for the mental health domain to -0.53 for the social functioning domain (P<0.01). Canonical correlation analysis showed that the overall overlap between the 2 instruments was moderately strong (canonical correlation coefficients r=0.707 and 0.572). The overall measured redundancies for MIDAS and SF-36 scales in this study were 35.4% and 11.5%, respectively. The stepwise linear regression model showed that the social functioning domain alone explained 27.9% of variance in the MIDAS scores. Bodily pain, physical functioning, and general health domains added an additional 11.4% of the explained variance in the regression model.

CONCLUSION

Despite the fact that these two measures were considerably correlated, the MIDAS and SF-36 were found to measure different aspects of the impact of headache for the sample investigated. The MIDAS questionnaire does not cover the emotional domain; therefore, an accompanying psychological questionnaire might help assess the outcome for headache studies.

Epidemiology of headache in Europe

The present review of epidemiologic studies on migraine and headache in Europe is part of a larger initiative by the European Brain Council to estimate the costs incurred because of brain disorders. Summarizing the data on 1-year prevalence, the proportion of adults in Europe reporting headache was 51%, migraine 14%, and 'chronic headache' (i.e. > or =15 days/month or 'daily') 4%. Generally, migraine, and to a lesser degree headache, are most prevalent during the most productive years of adulthood, from age 20 to 50 years. Several European studies document the negative influence of headache disorders on the quality of life, and health-economic studies indicate that 15% of adults were absent from work during the last year because of headache. Very few studies have been performed in Eastern Europe, and there are also surprisingly little data on tension-type headache from any country. Although the methodology and the quality of the published studies vary considerably, making direct comparisons between different countries difficult, the present review clearly demonstrates that headache disorders are extremely prevalent and have a vast impact on public health. The data collected should be used as arguments to increase resources to headache research and care for headache patients all over the continent.

Prevalence, burden, and cost of headache disorders

PURPOSE OF REVIEW

Documentation of disease impact, both on the individual and on society, is vital to ensure that healthcare resources are distributed according to the relative importance of the different disorders. For headache, international initiatives now promote the cause of headache sufferers by documenting the prevalence, burden, and cost. The present review aims to give an update on studies on these aspects of headache that have appeared since 2004.

RECENT FINDINGS

Some studies indicate that the headache prevalence may be increasing, but the evidence is conflicting. The disease burden and the costs of migraine are probably among the highest for the neurologic disorders, and it is probably as high in poor countries as in the rich. For other headaches, reliable data on impact are still scarce, but these disorders may be as important as migraine because they are even more prevalent.

SUMMARY

Robust and increasing evidence suggests that headache should be taken seriously as a public health problem, not only in the rich countries. More studies on the impact of non-migrainous headaches, largely of the tension type, are urgently needed for a full evaluation of the consequences of headache disorders.

Use of Complementary and Alternative Medicine by Patients With Chronic Tension-Type Headache: Results of a Headache Clinic Survey

OBJECTIVES

This study was undertaken to evaluate the rates, pattern, and presence of predictors of complementary and alternative medicine use in a clinical population of patients with chronic tension-type headache.

BACKGROUND

The use of complementary and alternative medicine in the treatment of headaches is a growing phenomenon about which little is known.

METHODS

A total of 110 chronic tension-type headache patients attending a headache clinic participated in a physician-administered structured interview designed to gather information on complementary and alternative medicine use.

RESULTS

Past use of complementary and alternative therapies was reported by 40% of the patients surveyed (22.7% in the previous year). Chronic tension-type headache patients prefer complementary and alternative practitioner-administered physical treatments to self-treatments, the most frequently used being chiropractic (21.9%), acupuncture (17.8%), and massage (17.8%). Only 41.1% of the patients perceived complementary and alternative therapies to be beneficial. The most common source of recommendation of complementary and alternative medicine was a friend or relative (41.1%). Most of the chronic tension-type headache patients used complementary and alternative treatment as a specific intervention for their headache (77.3%). Almost 60% of complementary and alternative medicine users had not informed their medical doctors of their use of complementary and alternative medicine. The most common reasons given for choosing to use a complementary or alternative therapy was the "potential improvement of headache" it offered (45.4%). The patients who had used more complementary and alternative treatments were found to be those recording a higher lifetime number of visits to conventional medical doctors, those with a comorbid psychiatric disorder, those enjoying a higher (household) income, and those who had never tried a preventive pharmacological treatment.

CONCLUSIONS

Our findings suggest that headache-clinic chronic tension-type headache patients, in their need of and quest for care, seek and explore both conventional and complementary and alternative therapies, even if only 41.1% of them perceived complementary treatments as effective. Physicians should be made aware of this patient-driven change in the medical climate in order to prevent misuse of health care resources and to be better equipped to meet patients' care requirements.

[Abuse pattern of analgesics in chronic daily headache: a study in the general population]

BACKGROUND AND OBJECTIVE

The abuse pattern of analgesics is not well known in persons with "chronic daily headache and analgesic abuse" (CHA) in the general population. The objective of this study was to know the type of analgesics used by pharmacological group and the active ingredient in subjects with CHA in a large sample of the general population.

PATIENTS AND METHODS

A questionnaire was distributed that investigated the frequency of headache and analgesic consumption among persons over 14 years (9,984 inhabitants) of the semiurban population of Santoña (Cantabria). A total of 4,855 subjects filled out the questionnaire. Although the CHA criteria require headache > or = 15 days a month, those individuals (n = 332) that report subjective consumption of analgesics for headache > or = 10 days in this period filled out a headache diary for one month. A total of 72 individuals fulfilled CHA criteria (1.48% of the general population). The varieties of CHA were classified according to the Silberstein et al criteria.

RESULTS

The greatest consumption corresponded to the simple analgesic group with 34.7% of all the subjects followed by those of combined analgesics and ergotaminics consumed by 27.8% and 22.2% respectively. A total of 12.5% took opioids alone or associated and triptans were in the fifth place. The latter were consumed by 2.8% of all the subjects. The active ingredients used most were: paracetamol (54%), caffeine (49%), ergotic derivatives (38%) and propyphenazone (35%). The subjects detected consumed a mean of 2.5 active ingredients simultaneously. The mean units consumed in their different presentation by the subjects with CHA was 50 units/month.

CONCLUSIONS

This study shows that CHA is a significant health care problem. In our setting, 85% of the persons with CHA of the population used analgesics and/or ergotics. These medications were given without prescription so that their obtention should be regulated in the pharmacy offices.

Medication-overuse headache in children: is initial preventive therapy necessary?

Chronic daily headaches can be a difficult problem in children as well as adults. Over half of the cases of chronic daily headaches in adults are thought to be due to medication-overuse headache, and treatment consists of discontinuation of these analgesics. Since many patients are also treated with preventive agents at the time of analgesic withdrawal, it is difficult to determine whether discontinuation alone is the most effective treatment. A retrospective study was performed to evaluate the outcomes of 43 children (ages 6-17 years) with medication-overuse headache 1 month after withdrawal of analgesics: 20 children received daily doses of a preventive medication, and 23 received no preventive medication. Headache reduction was assessed 1 month later. There was no difference in the percentage, with 90% or greater headache reduction at 1 month between children treated by withdrawal of analgesic drugs only and those receiving preventive medications (57% vs 50%, respectively). There was no influence of age, gender, use of triptans as rescue agents, or caffeine use on outcomes. A previous duration of headaches over 2 years was negatively correlated with overall outcome. We advise discontinuation of analgesics in all children with medication-overuse headache, without the necessity for starting daily preventive agents concurrently. Should headaches persist after 1 month, such agents can be added. (J Child Neurol 2006;21:45-48).

Medication overuse headache

Medication overuse headache (MOH) has developed into the third most common type of headache after tension-type headache and migraine. The prevalence of MOH is approximately 1% of the world's population and it shows an increasing trend as recent studies reveal a common involvement throughout the ages, even starting in childhood. All antiheadache drugs, such as triptans, analgesics, ergots and opioids, along with the common combination substances currently on the pharmacological market are capable of inducing MOH. New data on specific clinical features and mean critical monthly dosages and mean critical monthly intake frequencies are now available. The only effective treatment concept is consequent withdrawal therapy. Data of prospective studies on relapse rates and predictors of relapse after successful withdrawal therapy are presented.

Orbitofrontal cortex involvement in chronic analgesic-overuse headache evolving from episodic migraine

The way in which medication overuse transforms episodic migraine into chronic daily headache is unknown. To search for candidate brain areas involved in this process, we measured glucose metabolism with 18-FDG PET in 16 chronic migraineurs with analgesic overuse before and 3 weeks after medication withdrawal and compared the data with those of a control population (n = 68). Before withdrawal, the bilateral thalamus, orbitofrontal cortex (OFC), anterior cingulate gyrus, insula/ventral striatum and right inferior parietal lobule were hypometabolic, while the cerebellar vermis was hypermetabolic. All dysmetabolic areas recovered to almost normal glucose uptake after withdrawal of analgesics, except the OFC where a further metabolic decrease was found. A subanalysis showed that most of the orbitofrontal hypometabolism was due to eight patients overusing combination analgesics and/or an ergotamine-caffeine preparation. Medication overuse headache is thus associated with reversible metabolic changes in pain processing structures like other chronic pain disorders, but also with persistent orbitofrontal hypofunction. The latter is known to occur in drug dependence and could predispose subgroups of migraineurs to recurrent analgesic overuse.

El Cuestionario de Salud SF-36 español: una década de experiencia y nuevos desarrollos

OBJECTIVE

The Short Form-36 Health Survey (SF-36) is one of the most widely used and evaluated generic health-related quality of life (HRQL) questionnaires. After almost a decade of use in Spain, the present article critically reviews the content and metric properties of the Spanish version, as well as its new developments.

METHODS

A review of indexed articles that used the Spanish version of the SF-36 was performed in Medline (PubMed), the Spanish bibliographic databases IBECS and IME. Articles that provided information on the measurement model, reliability, validity, and responsiveness to change of the instrument were selected.

RESULTS

Seventy-nine articles were found, of which 17 evaluated the metric characteristics of the questionnaire. The reliability of the SF-36 scales was higher than the suggested standard (Cronbach's alpha) of 0.7 in 96% of the evaluations. Grouped evaluations obtained by meta-analysis were higher than 0.7 in all cases. The SF-36 showed good discrimination among severity groups, moderate correlations with clinical indicators, and high correlations with other HRQL instruments. Moreover, questionnaire scores predicted mortality and were able to detect improvement due to therapeutic interventions such as coronary angioplasty, benign prostatic hyperplasia surgery, and non-invasive positive pressure home ventilation. The new developments (norm-based scoring, version 2, the SF-12 and SF-8) improved both the metric properties and interpretation of the questionnaire.

CONCLUSIONS

The Spanish version of the SF-36 and its recently developed versions is a suitable instrument for use in medical research, as well as in clinical practice.

Assessment and management of disability in chronic daily headache

The problem of chronic daily headache is ubiquitous and affects up to 5% of the world's population. In most cases, it is associated with the overuse of symptomatic medications in patients with a history of migraine or tension-type headaches, indicating an urgent need for intensive public and professional education. In a minority, it develops de novo from episodic migraine without excessive drug intake. The condition is likely to have a biologic (rather than psychologic) basis. The degree with which it negatively impacts patients and their family is reviewed. Current treatment regimes are described, but it is noted that those currently employed are seldom adequate in the long term, possibly because of the unavailability of nonpharmacologic treatments to most people or because of the low frequency of use of preventative pharmacologic and lifestyle measures.

Low Income and Education Levels May Cause Medication Overuse and Chronicity in Migraine Patients

BACKGROUND

Frequent analgesic drug intake, especially in migraine patients, may induce the risk of medication overuse headache (MOH). The various conditions that may affect the development and the features of MOH have not been determined yet.

AIM

To compare MOH patients with migraine as pre-existing headache and episodic migraine patients according to socioeconomic and educational variables.

METHODS

Forty-six MOH patients with migraine as pre-existing headache and 61 migraine patients were included into study. The headache characteristics, socioeconomic and educational variables of MOH and migraine groups and subgroups divided according to the education (low/high education subgroups), and income (low/high income subgroups) levels were evaluated.

RESULTS

We found that mean duration of education was shorter in MOH patients than migraine patients. There was a negative correlation between duration of education and duration of MOH. The mean duration of MOH was longer and rate of low-income level was higher in patients with low-education level. The duration of education was lower in MOH patients with low income. The frequency of migraine attacks and low-income rate was also higher in low-educated migraine patients. The duration of education was shorter in migraine patients with low income.

CONCLUSION

We report that migraineurs with low socioeconomic status may have risk of developing MOH. A better identification of patients at risk of drug-associated headache may contribute to improved health in a group of patients with MOH.