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

BACKGROUND: Little is known about the duration of antibiotic use in hospital settings. We evaluated the duration of hospital antibiotic therapy (as a quality indicator proxy) for four commonly prescribed antibiotics (amoxicillin, co-amoxiclav, doxycycline and flucloxacillin) including the assessment of COVID-19 impact.

METHODS: 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 were calculated, stratified by routes of administration, 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<0.05), with the highest value among those antibiotic courses comprised of both oral and IV antibiotics ("Both" group). Significantly higher proportions of prescriptions within the "Both" group had a duration of > 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.

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.