Migraine diagnosis and treatment: results from the American Migraine Study II.

OBJECTIVE A population-based survey was conducted in 1999 to describe the patterns of migraine diagnosis and medication use in a representative sample of the US population and to compare results with a methodologically identical study conducted 10 years earlier. METHODS A survey mailed to a panel of 20 000 US households identified 3577 individuals with severe headache meeting a case definition for migraine based on the International Headache Society (IHS) criteria. Those with severe headache answered questions regarding physician diagnosis and use of medications for headache as well as headache-related disability. RESULTS A physician diagnosis of migraine was reported by 48% of survey participants who met IHS criteria for migraine in 1999, compared with 38% in 1989. A total of 41% of IHS-defined migraineurs used prescription drugs for headaches in 1999, compared with 37% in 1989. The proportion of IHS-defined migraineurs using only over-the-counter medications to treat their headaches was 57% in 1999, compared with 59% in 1989. In 1999, 37% of diagnosed and 21% of undiagnosed migraineurs reported 1 to 2 days of activity restriction per episode (P<.001); 38% of diagnosed and 24% of undiagnosed migraineurs missed at least 1 day of work or school in the previous 3 months (P<.001); 57% of diagnosed and 45% of undiagnosed migraineurs experienced at least a 50% reduction in work/school productivity (P<.001). CONCLUSIONS Diagnosis of migraine has increased over the past decade. Nonetheless, approximately half of migraineurs remain undiagnosed, and the increased rates of diagnosis of migraine have been accompanied by only a modest increase in the proportion using prescription medicines. Migraine continues to cause significant disability whether or not there has been a physician diagnosis. Given the availability of effective treatments, public health initiatives to improve patterns of care are warranted.