A New Approach to Identifying Avoidable Emergency Department Visits Among High-Need High-Cost Medicaid Patients.

Patients with high need and high costs (HNHCs) are frequent users of emergency departments (EDs), and some of their visits may be avoidable with better access to primary care. A better understanding of the reasons for ED use of HNHC patients can inform cost containment and quality improvement efforts. Our goal was to identify reasons for ED visits based on categories of services received by HNHC patients during the visit and to examine the likely role of different categories of primary care providers (PCPs) in reducing potentially preventable visits. We used the 2018 California Medicaid enrollment and claims data for HNHC patients with at least 1 PCP visit and 1 ED visit followed by discharge. These patients generated 539,798 ED visits. We conducted latent class analysis to classify visits and logistic regressions to examine associations between PCP type, visit, and patient characteristics with ED classes. We identified 6 classes of ED visits and considered 2 as acute care and 4 as nonacute care classes. The latter included a large class of ED visits (51%) by patients who received the fewest procedures. Patients within this group were more likely to have chronic and mental health conditions, weekend ED visits, live in rural locations, and attend group practices and health centers funded by the Health Resources and Services Administration. Our findings suggest that expanding after-hours services, providing medical emergency hotlines, and delivering comprehensive services within primary care may help circumvent costly and frequent nonacute ED visits among HNHC patients.