Epidemiology of emergency department visits for opioid overdose: a population-based study

To evaluate the rate of emergency department (ED) visits for opioid overdose and to examine whether frequent ED visits for opioid overdose are associated with more hospitalizations, near-fatal events, and health care spending.

Retrospective cohort study of adults with at least 1 ED visit for opioid overdose between January 1, 2010, and December 31, 2011, derived from population-based data of State Emergency Department Databases and State Inpatient Databases for 2 large and diverse states: California and Florida. Main outcome measures were hospitalizations for opioid overdose, near-fatal events (overdose involving mechanical ventilation), and hospital charges during the year after the first ED visit.

The analytic cohort comprised 19,831 unique patients with 21,609 ED visits for opioid overdose. During a 1-year period, 7% (95% CI, 7%-7%; n=1389 patients) of the patients had frequent (2 or more) ED visits, accounting for 15% (95% CI, 14%-15%; n=3167) of all opioid overdose ED visits. Middle age, male sex, public insurance, lower household income, and comorbidities (such as chronic pulmonary disease and neurological diseases) were associated with frequent ED visits (all P<.01). Overall, 53% (95% CI, 52%-54%; n=11,412) of the ED visits for opioid overdose resulted in hospitalizations; patients with frequent ED visits for opioid overdose had a higher likelihood of hospitalization (adjusted odds ratio, 3.98; 95% CI, 3.38-4.69). In addition, 10.0% (95% CI, 10%-10%; n=2161) of the ED visits led to near-fatal events; patients with frequent ED visits had a higher likelihood of a near-fatal event (adjusted odds ratio, 2.27; 95% CI, 1.96-2.66). Total charges in Florida were $208 million (95% CI, $200-$219 million).

In this population-based cohort, we found that frequent ED visits for opioid overdose were associated with a higher likelihood of future hospitalizations and near-fatal events.