The Economics of Antibiotic Resistance: A Systematic Review and Meta-analysis Based on Global Research.

Background: Antibiotic resistance (ABR) is a growing global health threat; reliable evidence on its impact is crucial for prioritising public health interventions.

Objective: This study provides an updated, systematic review and meta-analysis to determine the true effect size of resistant infections on economic and clinical outcomes. It also evaluates methodologies used in ABR economic literature, offering recommendations for improving future research.

Methods: Following PRISMA guidelines, 11,252 articles published between 2000 and 2022 were reviewed from several databases. Studies were included if they reported the economic costs of ABR in humans and compared resistant with susceptible infections. Meta-analyses were conducted using random intercept models; standardised mean difference (SMD) was used for length of stay, and odds ratio (OR) for mortality. The Mantel-Haenszel method was applied to obtain pooled estimates.

Results: Results showed that 73% of the studies were conducted in high-income economies, the majority were performed at tertiary care settings (71%) and 67% employed only a hospital perspective. The available evidence indicated that the attributable cost of resistant infections ranged from EUR - 21,629 to EUR 74,452 per patient episode (with Pseudomonas spp. causing the highest costs). The majority of studies (93%) found that patients with ABR incurred higher costs than their susceptible counterparts (72% report statistically significantly higher costs). Results from meta-analysis indicated that, on average, the excess in hospital stay attributable to resistant infections was 8.72 days (95% confidence interval (CI) [6.42; 11.02], SMD = 0.91) and the odds of premature death were significantly higher in the resistance group, with a risk increase of 65% (OR 95% CI [1.44; 1.88]). Conclusion The findings of this study take the first steps in providing reliable evidence; they could be valuable to researchers, policymakers and clinicians involved in ABR control and health promotion across countries. Similarly, the reported estimates may prove useful for future modelling studies aimed at assessing the long-term economic impact of ABR.