Assessing duration of antibiotic therapy across hospitals in Scotland including the impact of COVID-19 pandemic: a segmented interrupted time series analysis

Background
Inappropriate antibiotic use, including unnecessary longer duration of therapy, is the key driver for antimicrobial resistance. Yet, evidence on duration of antibiotic use in hospital settings is scarce. This study evaluated duration of hospital antibiotic therapy for four commonly prescribed antibiotics (amoxicillin, co-amoxiclav, doxycycline and flucloxacillin) including the assessment of COVID-19 impact.
Methods
This study was a repeated, cross-sectional study using the Hospital Electronic Prescribing and Medicines Administration system (January/2019-March/2022). Monthly median duration of therapy/duration categories (≤3 days, >3-5 days, >5-7 days, >7-10 days and >10 days) were calculated, stratified by routes of administration (oral, IV and “Both”), age and sex. Impact of COVID-19 was assessed using segmented time-series analysis.
Results
There were significant variations in the median duration of therapy across routes of administration (P 7 days compared to oral or IV. Duration of therapy overall differed significantly by age. Some small statistically significant changes in the level/trends of duration of therapy were observed in the post- COVID-19 period, albeit clinically insignificant.
Conclusions
No evidence for prolonged duration of therapy were observed, even during COVID-19 pandemic. Duration of IV therapy was relatively short suggesting timely clinical review and consideration of IV to oral switch. Longer duration of therapy was observed among older patients.