Objective.—To describe the prevalence, sociodemographic profile, and the burden of migraine in the United States in 1999 and to compare results with the original American Migraine Study, a 1989 population-based study employing identical methods.

Methods.—A validated, self-administered questionnaire was mailed to a sample of 20 000 households in the United States. Each household member with severe headache was asked to respond to questions about symptoms, frequency, and severity of headaches and about headache-related disability. Diagnostic criteria for migraine were based on those of the International Headache Society. This report is restricted to individuals 12 years and older.

Results.—Of the 43 527 age-eligible individuals, 29 727 responded to the questionnaire for a 68.3% response rate. The prevalence of migraine was 18.2% among females and 6.5% among males. Approximately 23% of households contained at least one member suffering from migraine. Migraine prevalence was higher in whites than in blacks and was inversely related to household income. Prevalence increased from aged 12 years to about aged 40 years and declined thereafter in both sexes. Fifty-three percent of respondents reported that their severe headaches caused substantial impairment in activities or required bed rest. Approximately 31% missed at least 1 day of work or school in the previous 3 months because of migraine; 51% reported that work or school productivity was reduced by at least 50%.

Conclusions.—Two methodologically identical national surveys in the United States conducted 10 years apart show that the prevalence and distribution of migraine have remained stable over the last decade. Migraine-associated disability remains substantial and pervasive. The number of migraineurs has increased from 23.6 million in 1989 to 27.9 million in 1999 commensurate with the growth of the population. Migraine is an important target for public health interventions because it is highly prevalent and disabling.

Prevalence and Burden of Migraine in the United States: Data From the American Migraine Study II

Objectives: 1) To reassess the prevalence of migraine in the United States; 2) to assess patterns of migraine treatment in the population; and 3) to contrast current patterns of preventive treatment use with recommendations for use from an expert headache panel. Methods: A validated self-administered headache questionnaire was mailed to 120,000 US households, representative of the US population. Migraineurs were identified according to the criteria of the second edition of the International Classification of Headache Disorders. Guidelines for preventive medication use were developed by a panel of headache experts. Criteria for consider or offer prevention were based on headache frequency and impair- ment. Results: We assessed 162,576 individuals aged 12 years or older. The 1-year period prevalence for migraine was 11.7% (17.1% in women and 5.6% in men). Prevalence peaked in middle life and was lower in adolescents and those older than age 60 years. Of all migraineurs, 31.3% had an attack frequency of three or more per month, and 53.7% reported severe impairment or the need for bed rest. In total, 25.7% met criteria for "offer prevention," and in an additional 13.1%, prevention should be considered. Just 13.0% reported current use of daily preventive migraine medication. Conclusions: Compared with previous studies, the epidemiologic profile of migraine has remained stable in the United States during the past 15 years. More than one in four migraineurs are candidates for preventive therapy, and a substantial proportion of those who might benefit from prevention do not receive it.

https://n.neurology.org/content/neurology/68/5/343.full.pdf

Migraine prevalence, disease burden, and the need for preventive therapy

Migraine is a common and sometimes debilitating disorder. This review describes the epidemiology, pathophysiology, and preventive and symptomatic treatment of migraine, with special attention to drug therapy with the triptans.

Migraine--current understanding and treatment.

Background: Migraine and other severe headaches can cause suffering and reduce functioning and productivity. Patients are the best source of information about such impact. Objective: To develop a new short form (HIT-6) for assessing the impact of headaches that has broad content coverage but is brief as well as reliable and valid enough to use in screening and monitoring patients in clinical research and practice. Methods: HIT-6 items were selected from an existing item pool of 54 items and from 35 items suggested by clinicians. Items were selected and modified based on content validity, item response theory (IRT) information functions, item internal consistency, distributions of scores, clinical validity, and linguistic analyses. The HIT-6 was evaluated in an Internet-based survey of headache sufferers (n = 1103) who were members of America Online (AOL). After 14 days, 540 participated in a follow-up survey. Results: HIT-6 covers six content categories represented in widely used surveys of headache impact. Internal consistency, alternate forms, and test–retest reliability estimates of HIT-6 were 0.89, 0.90, and 0.80, respectively. Individual patient score confidence intervals (95%) of app. ±5 were observed for 88% of all respondents. In tests of validity in discriminating across diagnostic and headache severity groups, relative validity (RV) coefficients of 0.82 and 1.00 were observed for HIT-6, in comparison with the Total Score. Patient-level classifications based in HIT-6 were accurate 88.7% of the time at the recommended cut-off score for a probability of migraine diagnosis. HIT-6 was responsive to self-reported changes in headache impact. Conclusions: The IRT model estimated for a 'pool' of items from widely used measures of headache impact was useful in constructing an efficient, reliable, and valid 'static' short form (HIT-6) for use in screening and monitoring patient outcomes.

A six-item short-form survey for measuring headache impact: The HIT-6?

The MIDAS Questionnaire was developed to assess headache-related disability with the aim of improving migraine care. Headache sufferers answer five questions, scoring the number of days, in the past 3 months, of activity limitations due to migraine. The internal consistency, test-retest reliability, and validity (accuracy) of the questionnaire were assessed in separate population-based studies of migraine sufferers. In addition, the face validity, ease of use, and clinical utility of the questionnaire were evaluated in a group of 49 physicians who independently rated disease severity and need for care in a diverse sample of migraine case histories. The test-retest Pearson correlation coefficient for the total MIDAS score was approximately 0.8. The MIDAS score was valid when compared with a reference diary-based measure of disability; the overall correlation between MIDAS and the diary-based measure was 0.63. The MIDAS score was also correlated with physicians' assessments of need for medical care (r = 0.69). From studies completed to date, the MIDAS Questionnaire has been shown to be internally consistent, highly reliable, valid, and correlates with physicians' clinical judgment. These features support its suitability for use in clinical practice. Use of the MIDAS Questionnaire may improve physician-patient communication about headache-related disability and may favorably influence health-care delivery for migraine patients.

Development and testing of the Migraine Disability Assessment (MIDAS) Questionnaire to assess headache-related disability

Background: The Migraine Disability Assessment (MIDAS) instrument is a five-item questionnaire developed to measure headache-related disability and improve doctor-patient communication about the functional consequences of migraine. Objectives: To examine the test-retest reliability and internal consistency of the five items and of the overall MIDAS score in population-based samples of migraine sufferers in two countries and to compare consistency across countries. Methods: Using a clinically validated telephone interview, population-based samples of migraine-headache sufferers were identified in the United States (Baltimore, MD) and the United Kingdom (Merton and Sutton, Surrey). Eligible individuals completed the MIDAS questionnaire on two occasions an average of 3 weeks apart. The MIDAS score is derived from five questions about missed time from work and household work (one question each about missed days and days with at least 50% reduced productivity) and missed days of nonwork activities. Results: A total of 97 migraine-headache sufferers from the United States and 100 from the United Kingdom completed the MIDAS questionnaire twice. Mean and median item values and overall MIDAS scores were similar between the United States and the United Kingdom. Test-retest Spearman correlations of individual items ranged from 0.46 to 0.78. No significant differences in item-specific correlations were observed between the United States and United Kingdom. The test-retest Pearson correlation of the MIDAS score (i.e., sum of lost days and reduced-effectiveness days in each domain) was 0.80 in the United States and 0.83 in the United Kingdom. The Cronbach α, a measure of internal consistency, was 0.76 in the United States and 0.73 in the United Kingdom. Conclusions: This is the first international population-based study to assess the reliability of a disability-related illness severity score for migraine. The reliability and internal consistency of the Migraine Disability Assessment score are similar to that of a previous questionnaire (Headache Impact Questionnaire). However, the Migraine Disability Assessment score requires fewer questions, is easier to score, and provides intuitively meaningful information on lost days of activity in three domains.

An international study to assess reliability of the Migraine Disability Assessment (MIDAS) score

Background. The Migraine Disability Assessment (MIDAS) score is used to quantify headache-related disability. In a previous study, we showed that the MIDAS score was highly reliable in population-based samples of migraine headache sufferers in two countries.Objectives. To examine the test–retest reliability and internal consistency of the five items comprising the MIDAS score and the overall MIDAS score in a population-based sample of both migraine and nonmigraine headache sufferers.Methods. Using a clinically validated telephone interview, a population-based sample of migraine and nonmigraine headache sufferers was identified in Baltimore, Maryland, USA. A total of 97 migraine cases and 80 nonmigraine subjects completed the MIDAS questionnaire on two occasions an average of 3 weeks apart. The MIDAS score is derived from five questions about missed time from work (or school) and household work (one question each about missed days and days with at least 50% reduced productivity) and missed days of nonwork ...

Reliability of the migraine disability assessment score in a population‐based sample of headache sufferers

The Migraine Disability Assessment (MIDAS) questionnaire is a brief, self-administered questionnaire designed to quantify headache-related disability over a 3 month period. The MIDAS score has been shown to have moderately high test-retest reliability in headache sufferers and is correlated with clinical judgment regarding the need for medical care. The aim of the study was to examine the validity of the MIDAS score, and the five items comprising the score, compared to data from a 90 day daily diary used, in part, to record acute disability from headache. In a population-based sample, 144 clinically diagnosed migraine headache sufferers were enrolled in a 90 day diary study and completed the MIDAS questionnaire at the end of the study. The daily diary was used to record detailed information on headache features as well as activity limitations in work, household chores, and non-work activities (social, family and leisure activities). The MIDAS score was the sum of missed work or school days, missed household chores days, missed non-work activity days, and days at work or school plus days of household chores where productivity was reduced by half or more in the last 3 months. Validity was assessed by comparing MIDAS items and the MIDAS score with equivalent measures derived from the diary. The MIDAS items for missed days of work or school (mean 0.96, median 0) and for missed days of household work (mean 3.64, median 2.0) were similar to the corresponding diary-based estimates of missed work or school (mean 1.23, median 0) and of missed household work (mean 3.93, median 2.01). Values for missed days of non-work activities (MIDAS mean 2.6 and median 1 versus diary mean 2.22 and median 0.95) were also similar. Responses to MIDAS questions about number of days where productivity was reduced by half or more in work (mean 3.77, median 2.00) and in household work (mean 3.92, median 2.00) significantly overestimated the corresponding diary-based measures for work (mean 2.94, median 1.06) and household work (mean 2.22, median 0.98). Nonetheless, the overall MIDAS score (mean 14.53, median 9.0) was not significantly different form the reference diary-based measure (mean 13.5, median 8.4). The correlation between the MIDAS summary score and an equivalent diary score was 0.63. The group estimate of the MIDAS score was found to be a valid estimate of a rigorous diary-based measure of disability. The mean and median values for the MIDAS score in a population-based sample of migraine cases were similar to equivalent diary measures. The correlation between the two measures was in the low moderate range, but expected given that two very different methods of data collection were compared.

Validity of the Migraine Disability Assessment (MIDAS) score in comparison to a diary-based measure in a population sample of migraine sufferers

ContextVarious guidelines recommend different strategies for selecting and
sequencing acute treatments for migraine. In step care, treatment is escalated
after first-line medications fail. In stratified care, initial treatment is
based on measurement of the severity of illness or other factors. These strategies
for migraine have not been rigorously evaluated.ObjectiveTo compare the clinical benefits of 3 strategies: stratified care, step
care within attacks, and step care across attacks, among patients with migraine.Design and SettingRandomized, controlled, parallel-group clinical trial conducted by the
Disability in Strategies Study group from December 1997 to March 1999 in 88
clinical centers in 13 countries.PatientsA total of 835 adult migraine patients with a Migraine Disability Assessment
Scale (MIDAS) grade of II, III, or IV were analyzed as the efficacy population;
the safety analysis included 930 patients.InterventionsPatients were randomly assigned to receive (1) stratified care (n =
279), in which patients with MIDAS grade II treated up to 6 attacks with aspirin,
800 to 1000 mg, plus metoclopramide, 10 mg, and patients with MIDAS grade
III and IV treated up to 6 attacks with zolmitriptan, 2.5 mg; (2) step care
across attacks (n = 271), in which initial treatment was with aspirin, 800
to 1000 mg, plus metoclopramide, 10 mg. Patients not responding in at least
2 of the first 3 attacks switched to zolmitriptan, 2.5 mg, to treat the remaining
3 attacks; and (3) step care within attacks (n = 285), in which initial treatment
for all attacks was with aspirin, 800 to 1000 mg, plus metoclopramide, 20
mg. Patients not responding to treatment after 2 hours in each attack escalated
treatment to zolmitriptan, 2.5 mg.Main Outcome MeasuresHeadache response, achieved if pain intensity was reduced from severe
or moderate at baseline to mild or no pain at 2 hours; and disability time
per treated attack at 4 hours for all 6 attacks, compared among the 3 groups.ResultsHeadache response at 2 hours was significantly greater across 6 attacks
in the stratified care treatment group (52.7%) than in either the step care
across attacks group (40.6%; P<.001) or the step
care within attacks group (36.4%; P<.001). Disability
time (6 attacks) was significantly lower in the stratified care group (mean
area under the curve [AUC], 185.0 mm · h) than in the step care across
attacks group (mean AUC, 209.4 mm · h; P<.001)
or the step care within attacks group (mean AUC, 199.7 mm · h; P<.001). The incidence of adverse events was higher
in the stratified care group (321 events) vs both step care groups (159 events
in across-attack group; 217 in within-attack group), although most events
were of mild-to-moderate intensity.ConclusionOur results indicate that as a treatment strategy, stratified care provides
significantly better clinical outcomes than step care strategies within or
across attacks as measured by headache response and disability time.

https://jamanetwork.com/journals/jama/articlepdf/193307/JOC00804.pdf

J. Sawyer

Papers

Development and testing of the Migraine Disability Assessment (MIDAS) Questionnaire to assess headache-related disability

An international study to assess reliability of the Migraine Disability Assessment (MIDAS) score

Reliability of the migraine disability assessment score in a population‐based sample of headache sufferers

Validity of the Migraine Disability Assessment (MIDAS) score in comparison to a diary-based measure in a population sample of migraine sufferers

Stratified Care vs Step Care Strategies for Migraine: The Disability in Strategies of Care (DISC) Study:A Randomized Trial