WORK-RELATED DISABILITY - RESULTS FROM THE AMERICAN MIGRAINE STUDY

(M)igraine headache is a highly prevalent, often severely painful and frequently disabling disorder. The 0indirect costs related to disabili ty greatly exceed the direct cost of medical care. The objective of th is paper is to describe work-related disability associated with migrai ne headache and predictors of disability. In a two-stage survey of the US population, we estimate missed workdays and impairment at work in a sample of 1663 migraine sufferers, age 18 years and older. Lost work day equivalents (LWDE) was derived as the sum of actual missed workday s and the product of percentage effectiveness at work and days at work with the most severe headache. Overall, reported actual lost workdays and reduced effectiveness at work contributed approximately equally t o total LWDE. A total of 51.1% of females and 38.1% of male migraineur s experienced six or more LWDE per year. This subgroup of migraine suf ferers accounted for about 90% of the total LWDE experienced by all re spondents. Among women, headache duration was the strongest predictor of LWDE followed by less significant associations with number of sympt oms and pain level. Among men, only pain level was significantly assoc iated with LWDE. Among sociodemographic factors, disability was more l ikely among older (40+) subjects and less likely among individuals wit h higher education and higher income (females only), even after adjust ing for headache features. Health-care interventions may yield the gre atest individual benefit (by reducing pain and disability) and the gre atest societal benefit (by reducing indirect costs) if they are direct ed to those who account for the greatest proportion of disability.