Quality indicators for appropriate inpatient antibiotic use: results from two national surveys in Italy, 2016-2022

Background: To address its high antimicrobial resistance (AMR) and antibiotic consumption rates, Italy introduced a national action plan to contrast AMR (PNCAR) in 2017. Aim: To investigate trends in antibiotic use, prescribing practices, and AMR rates in Italy through indicators of appropriate antibiotic use. Methods: Two point prevalence surveys (PPSs), according to ECDC methods and definitions, were conducted in 2016 and 2022. Indicators of appropriate antibiotic use were defined and measured. Antibiotic use prevalence and AMR rates for specific pathogen-drug combinations were calculated. To account for potential confounding factors, a propensity score matching approach was applied to compare the results of the two PPS editions using prevalence rate ratio (PRR). Results: Overall, 28,991 patients from 140 hospitals and 60,403 patients from 325 hospitals were included in 2016 and 2022 respectively. Patient characteristics remained stable, but patients were increasingly exposed to invasive procedures. The overall prevalence of antibiotic use decreased from 43.51 to 41.52 (PRR 0.95, 95% confidence interval, CI 0.94 - 0.97, p <0.001). Improvements in some prescribing practices were identified: the proportion of surgical prophylaxis lasting >1 day decreased from 55.99% to 52.15%, (PRR 0.94, 95% CI 0.90 - 0.98, p <0.001) and the proportion of culture-guided hospital infection treatments increased from 33.68% to 48.57% (PRR 1.30, 95% CI 1.22 - 1.38, p<0.05). Conversely, a significant rise in the proportion of last line/broad spectrum agents was recorded for most indications. Conclusion: This study provided a mapping of prescribing activity at national level, and defined measurable quality indicators, through which strengths and areas for improvement in prescribing practices were identified.