US Emergency Department Visits Attributed to Medication Harms, 2017-2019

Abstract

Importance: Assessing the scope of acute medication harms to patients should include both therapeutic and nontherapeutic medication use.

Objective: To describe the characteristics of emergency department (ED) visits for acute harms from both therapeutic and nontherapeutic medication use in the US.

Design, setting, and participants: Active, nationally representative, public health surveillance based on patient visits to 60 EDs in the US participating in the National Electronic Injury Surveillance System-Cooperative Adverse Drug Event Surveillance Project from 2017 through 2019.

Exposures: Medications implicated in ED visits, with visits attributed to medication harms (adverse events) based on the clinicians' diagnoses and supporting data documented in the medical record.

Main outcomes and measures: Nationally weighted estimates of ED visits and subsequent hospitalizations for medication harms.

Results: Based on 96 925 cases (mean patient age, 49 years; 55% female), there were an estimated 6.1 (95% CI, 4.8-7.5) ED visits for medication harms per 1000 population annually and 38.6% (95% CI, 35.2%-41.9%) resulted in hospitalization. Population rates of ED visits for medication harms were higher for patients aged 65 years or older than for those younger than 65 years (12.1 vs 5.0 [95% CI, 7.4-16.8 vs 4.1-5.8] per 1000 population). Overall, an estimated 69.1% (95% CI, 63.6%-74.7%) of ED visits for medication harms involved therapeutic medication use, but among patients younger than 45 years, an estimated 52.5% (95% CI, 48.1%-56.8%) of visits for medication harms involved nontherapeutic use. The proportions of ED visits for medication harms involving therapeutic use were lowest for barbiturates (6.3%), benzodiazepines (11.1%), nonopioid analgesics (15.7%), and antihistamines (21.8%). By age group, the most frequent medication types and intents of use associated with ED visits for medication harms were therapeutic use of anticoagulants (4.5 [95% CI, 2.3-6.7] per 1000 population) and diabetes agents (1.8 [95% CI, 1.3-2.3] per 1000 population) for patients aged 65 years and older; therapeutic use of diabetes agents (0.8 [95% CI, 0.5-1.0] per 1000 population) for patients aged 45 to 64 years; nontherapeutic use of benzodiazepines (1.0 [95% CI, 0.7-1.3] per 1000 population) for patients aged 25 to 44 years; and unsupervised medication exposures (2.2 [95% CI, 1.8-2.7] per 1000 population) and therapeutic use of antibiotics (1.4 [95% CI, 1.0-1.8] per 1000 population) for children younger than 5 years.

Conclusions and relevance: According to data from 60 nationally representative US emergency departments, visits attributed to medication harms in 2017-2019 were frequent, with variation in products and intent of use by age.

Figure 1.. Estimated Annual Emergency Department (ED) Visits for Medication Harms per 1000 Population, by Therapeutic vs Nontherapeutic Medication Use—US, 2017-2019

Estimates and 2-sided 95% CIs (error bars) were calculated from statistical weighting of 96 925 cases from 60 nationally representative hospitals participating in the National Electronic Injury Surveillance System–Cooperative Adverse Drug Event Surveillance Project for 2017-2019, Centers for Disease Control and Prevention. The population of each age group for 2017-2019 was calculated with intercensal estimates produced by the US Census Bureau. Patient age was missing for 13 cases (data not shown).

Figure 2.. Estimated Annual Emergency Department (ED) Visits for Medication Harms per 1000 Population, by Age and Intent of Medication Use—US, 2017-2019

Estimates were calculated from statistical weighting of 96 925 cases from 60 nationally representative hospitals participating in the National Electronic Injury Surveillance System–Cooperative Adverse Drug Event Surveillance Project for 2017-2019, Centers for Disease Control and Prevention. The population of each age group for 2017-2019 was calculated with intercensal estimates produced by the US Census Bureau. The estimate of ED visits for abuse, misuse, or overdose without indication of intent for children younger than 5 years is based on fewer than 20 cases and is considered statistically unstable. Patient age was missing for 13 cases (data not shown).