Drug-related emergency department visits in an elderly veteran population.

Background: Given that adverse drug events result in extensive costs and healthcare resource utilization, the goal is to better understand drug-related emergency department (ED) visits so that programs can be implemented to improve the quality of health care.

Objective: To (1) determine the incidence of drug-related ED visits at a large, tertiary care, Veterans Affairs hospital; (2) identify causes of these drug-related ED visits; (3) determine patient outcomes, healthcare resource utilization, and costs associated with these visits; and (4) determine the proportion of adverse drug reaction (ADR)-related ED visits that were spontaneously reported to the hospital's ADR reporting program.

Methods: We conducted a retrospective electronic chart review of all patients who visited the ED during the second week of each month in 2003. Causes for drug-related visits were identified. ADRs in this study included side effects, drug allergies, and drug-drug interactions (DDIs) and were assessed using the Naranjo probability scale.

Results: A total of 2169 patients were included in the study. Drug-related visits accounted for 12.6% of all ED visits. The main causes of drug-related visits were ADRs and nonadherence, which accounted for 33% and 19% of drug-related visits, respectively. Only 11% of these ADRs were spontaneously reported to the hospital's ADR reporting program. Thirty-five percent of drug-related visits led to hospitalizations, which resulted in an average length of stay of 9.3 days. The institution's total cost of drug-related visits was approximately 1.5 million US dollars over 12 weeks.

Conclusions: Many ED visits are drug related and often result in hospitalization and increased healthcare resource utilization. Only a minimal number of the ADRs resulting in ED visits are spontaneously reported to hospital ADR reporting programs.