Cost-effectiveness of influenza vaccination of older adults in the ED setting

Adults older than 50 years are at greater risk for death and severe disability from influenza. Persons in this age group, however, are frequently not vaccinated, despite extensive efforts by physicians to provide this preventive measure in primary care settings. We performed this study to determine if influenza vaccination of older adults in the emergency department (ED) may be cost-effective.

Using a probabilistic decision model with quasi-Markov modeling of a typical influenza season, we calculated costs and health outcomes for a hypothetical cohort of patients using parameters from the literature. Three ED-based intervention strategies were compared: (1) no vaccination offered, (2) vaccination offered to patients older than 65 years (limited strategy), and (3) vaccination offered to all patients who are 50 years and older (inclusive strategy). Outcomes were measured as costs, lives saved, and incremental costs per life saved. We performed deterministic and probabilistic sensitivity analyses.

Vaccination of patients 50 years of age and older results in an incremental cost of $34,610 per life saved when compared with the no-vaccination strategy. Limiting vaccination to only those older than 65 years results in an incremental cost of $13,084 per life saved. Results were sensitive to changes in vaccine cost but were insensitive to changes in other model parameters.

Vaccination of older adults against influenza in the ED setting is cost-effective, especially for those older than 65 years. Emergency departments may be an important setting for providing influenza vaccination to adults who may otherwise have remained unvaccinated.