A Retrospective Nested Cohort Study of Emergency Department Revisits for Migraine in New York City.

Objective: Migraine causes more than 1.2 million visits to US emergency departments (EDs) annually. Many of these visits are revisits among patients who had already been treated in an ED for migraine. The goal of this analysis was to determine the frequency of headache revisits among patients who present to an ED for management of migraine and sociodemographic factors associated with the revisit.

Methods: Using the New York City Department of Health and Mental Hygiene Syndromic Surveillance database, we conducted a retrospective nested cohort study. We analyzed visits from 18 NYC EDs with discharge diagnoses in the first 6 months of 2015. We conducted descriptive analyses to determine the frequency of headache revisit within 6 months of an index ED visit for migraine and the elapsed time to revisit. Using multivariable logistic regression, we assessed associations between age, sex, poverty, and revisit.

Results: Of 1052 ED visits with an ED discharge diagnosis of migraine during the first 6 months of 2015, 277 (26.3%) had a headache revisit within 6 months of their initial migraine visit and 131 (12.5%) had two or more revisits at the same hospital. Of the revisits for headache, 9% occur within 72 hours and 46% occur within 90 days of the initial migraine visit. Sex, age, and poverty level were not associated with an ED revisit.

Conclusion: More than a quarter of initial ED visits for migraine are followed by headache revisits in <6 months. Future work should target interventions to decrease the frequency of headache revisits.