The prevalence of headache in the adult population of Morocco: a cross-sectional population-based study.

BACKGROUND: The series of population-based studies conducted by the Global Campaign against Headache has, so far, included Pakistan and Saudi Arabia from the Eastern Mediterranean Region. The Maghreb countries of North Africa, also part of this Region, are geographically apart and culturally very different from these countries. Here we report a study in Morocco. METHODS: We applied the standardised methodology of Global Campaign studies, with cluster-randomized sampling in regions of Morocco selected to be representative of its diversities. In three of these regions, in accordance with this methodology, we made unannounced visits to randomly selected households and, from each, interviewed one randomly selected adult member (aged 18-65 years) using the HARDSHIP structured questionnaire translated into Moroccan Arabic and French. In a fourth region (Fès), because permission for such sampling was not given by the administrative authority, people were randomly stopped in streets and markets and, when willing, interviewed using the same questionnaire. This was a major protocol violation. RESULTS: We included 3,474 participants, 1,074 (41.7%) from Agadir, 1,079 (41.9%) from Marrakech, 422 (16.4%) from Tétouan and 899 from Fès. In a second protocol violation, interviewers failed to record the non-participating proportion. In the main analysis, excluding Fès, observed 1-year prevalence of any headache was 80.1% among females, 68.2% among males. Observed 1-day prevalence (headache yesterday) was 17.8%. After adjustment for age and gender, migraine prevalence was 30.8% (higher among females [aOR = 1.6]) and TTH prevalence 32.1% (lower among females [aOR = 0.8]). Headache on ≥ 15 days/month (H15+) was very common (10.5%), and in more than half of cases (5.9%) associated with acute medication overuse (on ≥ 15 days/month) and accordingly diagnosed as probable medication-overuse headache (pMOH). Both pMOH (aOR = 2.6) and other H15+ (aOR = 1.9) were more common among females. In the Fès sample, adjusted prevalences were similar, numerically but not significantly higher except for other H15+. CONCLUSIONS: While the 1-year prevalence of headache among adults in Morocco is similar to that of many other countries, migraine on the evidence here is at the upper end of the global range, but not outside it. H15 + and pMOH are very prevalent, contributing to the high one-day prevalence of headache.

The prevalence and demographic associations of headache in the adult population of Benin: a cross-sectional population-based study.

BACKGROUND: The Global Burden of Disease (GBD) study is increasingly well informed with regard to headache disorders, but sub-Saharan Africa (SSA) remains one of the large regions of the world with limited data directly derived from population-based studies. The Global Campaign against Headache has conducted three studies in this region: Ethiopia in the east, Zambia in the south and Cameroon in Central SSA. Here we report a similar study in Benin, the first from West SSA. METHODS: We used the same methods and questionnaire, applying cluster-randomized sampling in three regions of the country, randomly selecting households in each region, visiting these unannounced and randomly selecting one adult member (aged 18-65 years) of each household. The HARDSHIP structured questionnaire, translated into Central African French, was administered face-to-face by trained interviewers. Demographic enquiry was followed by diagnostic questions based on ICHD-3 criteria. RESULTS: From 2,550 households with eligible members, we recruited 2,400 participants (participating proportion 94.1%). Headache ever was reported by almost all (95.2%), this being the lifetime prevalence. Headache in the last year was reported by 74.9%. Age-, gender- and habitation-adjusted estimates of 1-year prevalence were 72.9% for all headache, 21.2% for migraine (including definite and probable), 43.1% for TTH (also including definite and probable), 4.5% for probable medication-overuse (pMOH) and 3.1% for other headache on ≥ 15 days/month. One-day (point) prevalence of headache was 14.8% according to reported headache on the day preceding interview. CONCLUSIONS: Overall, these findings are evidence that headache disorders are very common in Benin, a low-income country. The prevalence of pMOH, well above the estimated global mean of 1-2%, is evidence that poverty is not a bar to medication overuse. The findings are very much the same as those in a similar study in its near neighbour, Cameroon. With regard to migraine, they are reasonably in accord with two of three earlier studies in selected Beninese populations, which did not take account of probable migraine. This study adds to the hitherto limited knowledge of headache in SSA.

Headache in the adult population of Cameroon: prevalence estimates and demographic associations from a cross-sectional nationwide population-based study.

BACKGROUND: Knowledge of headache prevalence, and the burdens attributable to headache disorders, remains incomplete in sub-Saharan Africa (SSA): reliable studies have been conducted only in Zambia (southern SSA) and Ethiopia (eastern SSA). As part of the Global Campaign against Headache, we investigated the prevalence of headache in Cameroon, in Central SSA. METHODS: We used the same methodology as the studies in Zambia and Ethiopia, employing cluster-randomized sampling in four regions of Cameroon, selected to reflect the country's geographic, ethnic and cultural diversities. We visited, unannounced, randomly selected households in each region, and randomly selected one adult member (aged 18-65 years) of each. Trained interviewers administered the Headache-Attributed Restriction, Disability and Impaired Participation (HARDSHIP) structured questionnaire, developed by an international expert consensus group and translated into Central African French. Demographic enquiry was followed by diagnostic questions based on ICHD-3 criteria. RESULTS: Headache was a near-universal experience in Cameroon (lifetime prevalence: 94.8%). Observed 1-year prevalence of headache was 77.1%. Age- and gender-adjusted estimates were 76.4% (95% confidence interval: 74.9-77.9) for any headache, 17.9% (16.6-19.3) for migraine (definite + probable), 44.4% (42.6-46.2) for tension-type headache (TTH; also definite + probable), 6.5% (5.7-7.4) for probable medication-overuse headache (pMOH) and 6.6% (5.8-7.6) for other headache on ≥ 15 days/month (H15 +). One-day prevalence ("headache yesterday") was 15.3%. Gender differentials were as expected (more migraine and pMOH among females, and rather more TTH among males). pMOH increased in prevalence until age 55 years, then declined somewhat. Migraine and TTH were both associated with urban dwelling, pMOH, in contrast, with rural dwelling. CONCLUSIONS: Headache disorders are prevalent in Cameroon. As in Zambia and Ethiopia, estimates for both migraine and TTH exceed global mean estimates. Attributable burden is yet to be reported, but these findings must lead to further research, and measures to develop and implement headache services in Cameroon, with appropriate management and preventative strategies.

The HARDSHIP databases: a forthcoming free good from the Global Campaign against Headache.

In order to pursue its purpose of reducing the global burden of headache, the Global Campaign against Headache has gathered data on headache-attributed burden from countries worldwide. These data, from the individual participants in adult population-based studies and child and adolescent schools-based studies, are being collated in two databases, which will be powerful resources for research and teaching and rich information sources for health policy.Here we briefly describe the structure and content of these databases, and announce the intention to make them available in due course as a free good.

The relationship between headache-attributed disability and lost productivity: 2. Empirical evidence from population-based studies in nine disparate countries.

BACKGROUND: Headache disorders are disabling, with major consequences for productivity, yet the literature is silent on the relationship between headache-attributed disability and lost productivity, often erroneously regarding the two as synonymous. We evaluated the relationship empirically, having earlier found that investment in structured headache services would be cost saving, not merely cost-effective, if reductions in headache-attributed disability led to > 20% pro rata recovery of lost productivity. METHODS: We used individual participant data from Global Campaign population-based studies conducted in China, Ethiopia, India, Nepal, Pakistan and Russia, and from Eurolight in Lithuania, Luxembourg and Spain. We assessed relationships in migraine and probable medication-overuse headache (pMOH), the most disabling common headache disorders. Available symptom data included headache frequency, usual duration and usual intensity. We used frequency and duration to estimate proportion of time in ictal state (pTIS). Disability, in the sense used by the Global Burden of Disease study, was measured as the product of pTIS and disability weight for the ictal state. Impairment was measured as pTIS * intensity. Lost productivity was measured as lost days (absence or < 50% productivity) from paid work and corresponding losses from household work over the preceding 3 months. We used Spearman correlation and linear regression analyses. RESULTS: For migraine, in a linear model, we found positive associations with lost paid worktime, significant (p < 0.05) in many countries and highly significant (p < 0.001) in some despite low values of R2 (0-0.16) due to high variance. With lost household worktime and total lost productivity (paid + household), associations were highly significant in almost all countries, although still with low R2 (0.04-0.22). Applying the regression equations for each country to the population mean migraine-attributed disability, we found pro rata recoveries of lost productivity in the range 16-56% (> 20% in all countries but Pakistan). Analysing impairment rather than disability increased variability. For pMOH, with smaller numbers, associations were generally weaker, occasionally negative and mostly not significant. CONCLUSION: Relief of disability through effective treatment of migraine is expected, in most countries, to recover > 20% pro rata of lost productivity, above the threshold for investment in structured headache services to be cost saving.

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.

The prevalence of primary headache disorders in Saudi Arabia: a cross-sectional population-based study.

BACKGROUND: The large geographical gaps in our knowledge of the prevalence and burden of headache disorders include most of Eastern Mediterranean Region (EMR). Following a nationwide population-based study in Pakistan, we present here a similar study from Kingdom of Saudi Arabia (KSA). Both were conducted as projects within the Global Campaign against Headache The two purposes of this study were to inform national health policy and contribute to global knowledge of headache disorders. METHODS: We surveyed Arabic-speaking adults aged 18-65 years in all 13 regions of KSA. While previous Global Campaign studies have engaged participants by calling at randomly selected households, the culture of KSA made this unacceptable. Participants were, instead, contacted by cell-phone (since cell-phone coverage exceeded 100% in KSA), using random-digit dialling. Trained interviewers used a culturally adapted version of the Headache-Attributed Restriction, Disability, Social Handicap and Impaired Participation (HARDSHIP) questionnaire, with diagnostic enquiry based on ICHD-II. We estimated 1-year prevalences of the headache disorders of public-health importance (migraine, tension-type headache [TTH] and probable medication-overuse headache [pMOH]) and examined their associations with demographic variables. RESULTS: A total of 2316 participants (mean age of 32.2 ± 10.7 years; 62.3% male; 37.7% female) were included (participation proportion 86.5%). Gender and age distributions imperfectly matched those of the national population, requiring adjustments for these to prevalence estimates. Observed 1-year prevalence of all headache was 77.2%, reducing to 65.8% when adjusted. For headache types, adjusted 1-year prevalences were migraine 25.0%, TTH 34.1%, pMOH 2.0% and other headache on ≥15 days/month 2.3%. Adjusted 1-day prevalence of any headache was 11.5%. Migraine and pMOH were associated with female gender (ORs: 1.7 and 4.7; p < 0.0001). Migraine was negatively associated with age > 45 years (OR: 0.4; p = 0.0143) while pMOH was most prevalent in those aged 46-55 years (OR: 2.7; p = 0.0415). TTH reportedly became more common with increasing level of education. CONCLUSION: Prevalences of migraine and TTH in KSA are considerably higher than global averages (which may be underestimated), and not very different from those in Pakistan. There is more pMOH in KSA than in Pakistan, reflecting, probably, its higher-income status and greater urbanisation (facilitating access to medication).

Primary headache disorders among the adult population of Mongolia: prevalences and associations from a population-based survey.

BACKGROUND: In the ongoing Global Campaign endeavour to improve knowledge and awareness of headache prevalence worldwide, Mongolia is a country of interest. It sits between Russia and China, in which prevalence is, respectively, much higher and much lower than the estimated global mean. We conducted a population-based study in Mongolia both to add to knowledge and to inform local health policy. METHODS: Using standardized methodology with cluster random sampling, we selected Mongolian adults (aged 18-65 years) from five regions reflecting the country's diversities. They were interviewed by trained researchers, cold-calling at their homes, using the Headache-Attributed Restriction, Disability, Social Handicap and Impaired Participation (HARDSHIP) structured questionnaire following pilot-testing. ICHD-3 beta diagnostic criteria were applied. RESULTS: N = 2043 (mean age 38.0 [±13.4] years, 40% urban-dwelling and 60% rural), with a non-participation proportion of 1.7%. Males were somewhat underrepresented, for which corrections were made. The crude 1-year prevalence of any headache was 66.1% (95% CI: 64.0-68.2%), with a strong female preponderance (OR: 2.2; p < 0.0001). Age- and gender-adjusted prevalences were: migraine 23.1% (for females, OR = 2.2; p < 0.0001); tension-type headache (TTH) 29.1% (no gender difference); probable medication-overuse headache (pMOH) 5.7% (trending towards higher in females); other headache on ≥15 days/month 5.0% (for females, OR = 2.2; p = 0.0008). Unclassified cases were only 35 (1.7%). Any headache yesterday was reported by 410 (20.1%; for females, OR = 2.4; p < 0.0001). Only pMOH showed a strong association with age, peaking in middle years with a 5-fold increase in prevalence. Migraine showed a consistent association with educational level, while pMOH showed the reverse, and was also more common among other groups than among participants who were single (never married). Migraine was less common among rural participants than urban (OR: 0.80; p = 0.0326), while pMOH again showed the reverse (OR: 2.4; p < 0.0001). Finally, pMOH (but not migraine or TTH) was significantly associated with obesity (OR: 1.8; p = 0.0214). CONCLUSION: Headache disorders are common in Mongolia, with, most notably, a very high prevalence of headache on ≥15 days/month corroborated by the high prevalence of headache yesterday. The picture is very like that in Russia, and dissimilar to China. There are messages for national health policy.

Prevalence and burden of headache disorders in Lithuania and their public-health and policy implications: a population-based study within the Eurolight Project.

BACKGROUND: The Eurolight project assessed the impact of headache disorders in ten EU countries, using the same structured questionnaire but varying sampling methods. In Lithuania, sample selection employed methods in line with consensus recommendations for population-based burden-of-headache studies. METHODS: The survey was cross-sectional. We identified, from the Residents' Register Service, a sample of inhabitants of Kaunas city and surrounding Kaunas region reflecting age (in the range 18-65 years), gender and rural/urban distributions of Lithuania. Medical students called unannounced at their homes and conducted face-to-face interviews employing a structured questionnaire. RESULTS: Of 1137 people in the pre-identified sample, 573 (male 237 [41.4%], female 336 [58.6%]; mean age 40.9 ± 13.8 years) completed interviews (participation proportion: 50.4%). Gender-adjusted 1-year prevalences were: any headache 74.7%; migraine 18.8%; tension-type headache (TTH) 42.2%; all headache on ≥15 days/month 8.6%; probable medication-overuse headache (pMOH) 3.2%. Migraine (OR: 3.6) and pMOH (OR: 2.9) were associated with female gender. All headache types except TTH were associated with significantly diminished quality of life. Migraine caused a mean 4.5% loss in paid worktime per affected male and 3.5% per affected female. Lost per-person times due to TTH were much less, but to pMOH and other headache on ≥15 days/month much higher. Among the entire workforce, lost productivity to migraine was estimated at 0.7%, to TTH 0.3% and to pMOH or other headache on ≥15 days/month 0.5%. The total of 1.5% may translate directly into lost GDP. Alternative calculations based on headache yesterday (with little recall error) produced, for all headache, a corroborating 1.7%. Similar losses from household work would also drain the nation's economy. Our findings were comparable to those from earlier studies using similar methods in Russia and Georgia. CONCLUSIONS: The multiple burdens from headache in Lithuania indicate substantial ill-health and unmet need for health care. The heavy burdens on individuals are matched by heavy economic burden. Of particular concern is the high prevalence of headache on ≥15 days/month, seen also in Russia and Georgia. Health policy in Lithuania must heed WHO's advice that effective treatment of headache, clearly desirable for its health benefits, is also expected to be cost-saving.

The burden of headache disorders in Ethiopia: national estimates from a population-based door-to-door survey.

BACKGROUND: Headache disorders are the third-highest cause of disability worldwide, with migraine and medication-overuse headache (MOH) the major contributors. In Ethiopia we have shown these disorders to be highly prevalent: migraine 17.7%, TTH 20.6%, probable MOH (pMOH) 0.7%, any headache yesterday (HY) 6.4%. To inform local health policy, we now estimate disability and other burdens attributable to headache in this country. METHODS: In a cross-sectional survey using cluster-randomized sampling, we visited households unannounced in four diverse regions (urban and rural) of Ethiopia. We interviewed one member (18-65 years old) of each household using the HARDSHIP structured questionnaire. Screening and diagnostic questions based on ICHD-II were followed by burden enquiry in multiple domains. We estimated disability using disability weights (DWs) from the Global Burden of Disease 2013 study. RESULTS: We interviewed 2385 participants (1064 [44.7%] male, 596 [25.0%] urban; participating proportion 99.8%). Reported mean intensity of migraine was 2.6 (scale 1-3). People with migraine spent 11.7% of their time in the ictal state (DW: 0.441); they were therefore 5.2% disabled overall. Pain and disability from TTH were much lower. Mean intensity of pMOH was 2.95. People with pMOH spent 60.2% of time with headache (DW: 0.223), and were 13.4% disabled. Average proportions of per-person lost productive time were, for migraine, 4.5% from paid work, 5.3% from household work; for pMOH they were 29.2% and 16.0%. There were highly-disabled minorities, and large gender differences, males losing more paid workdays, females more household workdays. All headache types were associated with impairments in quality of life. Across the population aged 18-65 years (effectively the working population), disability from headache was 1.4%, with 1.6% of workdays lost (half from migraine). Estimates from HY, eliminating recall error, were highly compatible. CONCLUSIONS: Ethiopia is a low-income country, and cannot afford these losses - including, perhaps, 1.6% of GDP. Political action is necessary, aimed at mitigating both the economic burden and the associated ill health. WHO has recommended structured headache services with their basis in primary care as the most efficient, effective, affordable and equitable solution, potentially cost-saving. We believe they can be implemented within Ethiopia's existing health-care infrastructure.

The prevalence of primary headache disorders in Ethiopia.

BACKGROUND: Knowledge of the epidemiology of primary headache disorders in sub-Saharan Africa (SSA) remains very limited. We performed a population-based survey in rural and urban areas of Ethiopia, using methods similar to those of an earlier study in Zambia and tested in multiple other countries by Lifting The Burden. METHODS: In a cross-sectional survey we visited households unannounced in four regions of Ethiopia: the mostly urban populations in Addis Ababa and its environs and rural populations of selected districts in Oromia, Amhara and South Nations Nationalities and People's Regions States (SNNPRS). We used cluster-randomized sampling: within clusters we randomly selected households, and one adult member (18-65 years old) of each household. The HARDSHIP structured questionnaire, translated into the local languages, was administered face-to-face by trained interviewers. Demographic enquiry was followed by diagnostic questions based on ICHD-II criteria. RESULTS: From 2,528 households approached, 2,385 of 2,391 eligible members (1,064 [44.7%] male, 596 [25.0%] urban) consented to interview (participating proportion 99.8%). Headache in the preceding year was reported by 1,071 participants (44.9% [95% CI: 42.4-46.3]; males 37.7%, females 49.9%), and headache yesterday by 170 (7.1% [6.2-8.2]; males 45 [4.1%], females 125 [9.2%]). Adjusted for gender, age and habitation (urban/rural), 1-year prevalence of migraine was 17.7%, of tension-type headache (TTH) 20.6%, of all headache on ≥15 days/month 3.2%, and of probable medication-overuse headache (pMOH) 0.7%. The adjusted prevalence of headache yesterday was 6.4%. Very few cases (1.6%) were unclassifiable. All headache disorders were more common in females. TTH was less common in urban areas (OR: 0.3; p < 0.0001), but pMOH was very strongly associated (OR: 6.1; p < 0.0001) with urban dwelling. Education was negatively associated with migraine (OR: 0.5-0.7; p < 0.05) but (at university level) positively with pMOH (OR: 2.9; p = 0.067). Income above ETB 500/month showed similar associations: negatively with migraine (OR: 0.8; p = 0.035), positively with pMOH (OR: 2.1; p = 0.164). CONCLUSIONS: Findings for migraine and TTH in Ethiopia were quite similar to those from Zambia, another SSA country; pMOH was much less prevalent but, as in Zambia, essentially an urban problem. Primary headache disorders are at least as prevalent in SSA as in high-income western countries.

Headache, depression and anxiety: associations in the Eurolight project.

BACKGROUND: Headache disorders and psychiatric disorders are both common, while evidence, mostly pertaining to migraine, suggests they are comorbid more often than might be expected by chance. There are good reasons for establishing whether they are: symptoms of comorbid illnesses may summate synergistically; comorbidities hinder management, negatively influencing outcomes; high-level comorbidity indicates that, where one disease occurs, the other should be looked for. The Eurolight project gathered population-based data on these disorders from 6624 participants. METHODS: Eurolight was a cross-sectional survey sampling from the adult populations (18-65 years) of 10 EU countries. We used data from six. The questionnaire included headache-diagnostic questions based on ICHD-II, the Headache-Attributed Lost Time (HALT) questionnaire, and HADS for depression and anxiety. We estimated odds ratios (ORs) to show associations between migraine, tension-type headache (TTH) or probable medication-overuse headache (pMOH) and depression or anxiety. RESULTS: pMOH was most strongly associated with both psychiatric disorders: for depression, ORs (vs no headache) were 5.5 [2.2-13.5] (p < 0.0001) in males, 5.5 [2.9-10.5] (p < 0.0001) in females; for anxiety, ORs were 10.4 [4.9-21.8] (p < 0.0001) and 7.1 [4.5-11.2] (p < 0.0001). Migraine was also associated with both: for depression, ORs were 2.1 [1.3-3.4] (p = 0.002) and 1.8 [1.1-3.1] (p = 0.030); for anxiety 4.2 [2.8-6.3] (p < 0.0001) and 2.4 [1.7-3.4] (p < 0.0001). TTH showed associations only with anxiety: ORs 2.5 [1.7-3.7] (p < 0.0001) for males, 1.5 [1.1-2.1] (p = 0.021) for females. Participants with migraine carried 19.1 % probability of comorbid anxiety, 6.9 % of depression and 5.1 % of both, higher than the representative general-population sample (14.3, 5.6 and 3.8 %). Probabilities in those with MOH were 38.8, 16.9 and 14.4 %; in TTH, they did not exceed those of the whole sample. Comorbid psychiatric disorder did not add to headache-attributed productive time losses, but weak associations existed (R (2) = 0.020-0.082) for all headache types between lost productive time and probabilities of depression and, less so, anxiety. CONCLUSION: In this large study we confirmed that depression and especially anxiety are comorbid more than by chance with migraine, and showed the same is true, but more strongly, with MOH. Arguably, migraine patients and, more certainly, MOH patients should be screened with HADS in pursuit of best outcomes.

Interictal burden attributable to episodic headache: findings from the Eurolight project.

BACKGROUND: Most primary headaches are episodic, and most estimates of the heavy disability burden attributed to headache derive from epidemiological data focused on the episodic subtypes of migraine and tension-type headache (TTH). These disorders give rise directly but intermittently to symptom burden. Nevertheless, people with these disorders may not be symptom-free between attacks. We analysed the Eurolight dataset for interictal burden. METHODS: Eurolight was a cross-sectional survey using modified cluster sampling from the adult population (18-65 years) in 10 countries of the European Union. We used data from nine. The questionnaire included headache-diagnostic questions based on ICHD-II and several question sets addressing impact, including interictal and cumulative burdens. RESULTS: There were 6455 participants with headache (male 2444 [37.9 %]). Interictal symptoms were reported by 26.0 % of those with migraine and 18.9 % with TTH: interictal anxiety by 10.6 % with migraine and avoidance (lifestyle compromise) by 14.8 %, both much more common than in TTH (3.1 % [OR 3.8] and 4.7 % [OR 3.5] respectively). Mean time spent in the interictal state was 317 days/year for migraine, 331 days/year for TTH. Those who were "rarely" or "never" in control of their headaches (migraine 15.2 %, TTH 9.6 %) had significantly raised odds of interictal anxiety, avoidance and other interictal symptoms. Among those with migraine, interictal anxiety increased markedly with headache intensity and frequency, avoidance less so but still significantly. Lost productive time was associated with high ORs (up to 5.3) of anxiety and avoidance. A third (32.9 %) with migraine and a quarter (26.7 %) with TTH (difference: p < 0.0001) were reluctant to tell others of their headaches. About 10 % with each disorder felt families and friends did not understand their headaches. Nearly 12 % with migraine reported their employers and colleagues did not. Regarding cumulative burden, 11.8 % reported they had done less well in education because of headache, 5.9 % reported reduced earnings and 7.4 % that their careers had suffered. CONCLUSIONS: Interictal burden in those with episodic headache is common, more so in migraine than TTH. Some elements have the potential to be profoundly consequential. New methodology is needed to measure interictal burden if descriptions of headache burden are to be complete.

Harry Potter and the curse of headache.

Headache disorders are common in children and adolescents. Even young male Wizards are disabled by them. In this article we review Harry Potter's headaches as described in the biographical series by JK Rowling. Moreover, we attempt to classify them. Regrettably we are not privy to the Wizard system of classifying headache disorders and are therefore limited to the Muggle method, the International Classification of Headache Disorders, 2nd edition (ICHD-II). Harry's headaches are recurrent. Although conforming to a basic stereotype, and constant in location, throughout the 6 years of his adolescence so far described they have shown a tendency to progression. Later descriptions include a range of accompanying symptoms. Despite some quite unusual features, they meet all but one of the ICHD-II criteria for migraine, so allowing the diagnosis of 1.6 Probable migraine.