National Patterns of Emergency Department Use for Women with Endometriosis, 2006-2015.

Introduction: Endometriosis is a burdensome chronic condition for which conservative management is often recommended when indicated. Nonetheless, some women seek care for endometriosis in the emergency department (ED). We evaluated trends in ED visits for endometriosis from 2006 to 2015. Materials and Methods: Nationally representative estimates of ED visits for endometriosis by women aged 18-49 were extracted from the Health Care Utilization Project Nationwide Emergency Department Sample into three cohorts by calendar years 2006-2007, 2010-2011, and 2014-Q3 2015. Visits with a principal diagnosis code of endometriosis (International Classification of Disease, 9th Edition, Clinical Modification, code 617.x) were included. Patient and hospital characteristics were compared across cohorts using analysis of variance. Trends in the proportion of ED visits ending in inpatient admission and in mean charges (2015 USD) were assessed using generalized linear models controlling for patient and hospital characteristics. Results: The annual number of ED visits nationally was stable at ∼15,000 visits per year during 2006-2015. From 2006-2007 to 2014-2015, the composition of ED visits shifted away from private pay (42.0% vs. 35.3%) and uninsured (23.6% vs. 16.6%) to Medicaid (26.7% vs. 40.1%) and became more concentrated in metro-teaching hospitals (33.9% vs. 51.9%) (p < 0.001 for all). Inpatient admission rates declined from 20.1% to 9.2% (p < 0.001). Mean ED charges increased from $2458 to $4953 (p < 0.001). Conclusion: During 2006-2015, the number of ED visits for endometriosis remained stable, the inpatient admission/transfer rate declined by half, and mean charges per visit doubled.