Effects of States' Methods for Estimating Nonfatal Overdose, United States, 2021.

Objective: Previous nonfatal overdose is a key risk factor for drug overdose death; however, current nonfatal overdose surveillance is limited to people who receive medical attention. We identified states that tracked nonfatal overdoses treated in prehospital and hospital care settings, assessed the effects of different surveillance methods on the magnitude of nonfatal overdose estimates, and estimated states' nonfatal-to-fatal overdose ratio.

Methods: Two analysts independently reviewed state websites to characterize states' methods of capturing nonfatal overdose events from December 2022 through February 2023. We collected information on surveillance methods in 5 states that met the inclusion criteria, including data source, measure specification, drug(s) involved, and whether states performed deduplication or published mutually exclusive measure specifications to capture unique events across care settings. We calculated nonfatal-to-fatal overdose ratios to assess the effects of different data sources on estimates of nonfatal overdoses.

Results: Illinois, Maine, North Carolina, and West Virginia used syndromic surveillance data and New Jersey used hospital discharge data to track nonfatal overdose-related emergency department visits. Illinois and West Virginia tracked nonfatal overdose-related encounters with emergency medical services. Other states tracked opioid overdoses reversed following naloxone administration by emergency medical services, law enforcement, and community members. Maine, New Jersey, and West Virginia published nonfatal overdose information by using mutually exclusive measure specifications; the number of nonfatal overdoses per fatal overdose in these states ranged from approximately 5:1 to 14:1.

Practice implications: Establishing a standard framework to combine data from existing national surveillance systems in prehospital and hospital care settings can improve nonfatal overdose estimates and enable comparisons between jurisdictions to help decision makers identify areas most in need of essential services.