The association between antibiotic consumption and antimicrobial resistance-related mortality and costs: An analysis of European country-level data

Background While antibiotic use is recognized to contribute to antimicrobial resistance (AMR), the magnitude of its impact on AMR-related harms is not well understood. This study quantifies the association between antibiotic consumption and AMR-related mortality and costs. Methods Antibiotic consumption expressed in defined daily dose per 1000 inhabitants per day (DID) was sourced from pharmaceutical sales data from 30 European countries. Linear regression models were fitted to assess the association between antibiotic consumption and (1) AMR-related mortality in 2023 and (2) AMR-related healthcare costs in 2021. Estimates were adjusted for key confounders, including median age, gross domestic product, and hospital bed density. Leave-one-out and time-lag sensitivity analysis were performed to test robustness. Results Each unit increase in DID of average antibiotic consumption was associated with 0.3 (95% confidence interval: 0.2–0.5) additional AMR-related deaths per 100 000, and an increase in AMR-related costs of 5.6% (95% confidence interval: 1.8%–9.3%), holding all other variables constant. Mortality estimates were robust across sensitivity analyses, while cost estimates were sensitive to excluding outliers. Using antibiotic consumption from earlier years did not significantly affect the results. Conclusions This ecological study demonstrated that antibiotic consumption is positively associated with AMR-related mortality and costs across European countries. Despite the ecological nature of this study, the presented quantitative estimates can be used to inform health policy analyses of antibiotic interventions. Although missing data and context-specific factors may have limited the robustness of the cost association, these findings suggest that reducing unnecessary antibiotic consumption could help lower AMR-related mortality and healthcare costs.