Antimicrobial stewardship during the COVID-19 epidemic: population-based cohort study and interrupted time series analysis in the United Kingdom

Background. The COVID-19 pandemic has altered the context for antimicrobial stewardship in primary care. Aim: To assess the effect of the pandemic on antibiotic prescribing, accounting for changes in consultations for respiratory and urinary tract infections (RTIs/UTIs). Design and Setting: Population-based cohort study using the UK Clinical Practice Research Datalink (CPRD) (January 2017 to September 2020). Method: Interrupted time series analysis evaluated changes in antibiotic prescribing and RTI/UTI consultations adjusting for age, gender, season and secular trends. We assessed the proportion of COVID-19 episodes associated with antibiotic prescribing. Results: There were 253,655 registered patients in 2017 and 232,218 in 2020 with 559,461 antibiotic prescriptions, 216,110 RTI consultations and 36,402 UTI consultations. Compared to pre-pandemic months, March 2020 was associated with higher prescribing (adjusted rate ratio 1.13; 95% confidence interval 1.11 to 1.16). Prescribing fell below predicted rates between April and August 2020, reaching a minimum in May (0.73, 0.71 to 0.75). Pandemic months were associated with lower rates of RTI/UTI consultations, particularly in April for RTIs (0.23; 0.22 to 0.25). There were small reductions in the proportion of RTI consultations with antibiotic prescribed and no reduction for UTIs. Among 25,889 COVID-19 patients, 2,942 (11%) had antibiotics within a COVID-19 episode. Conclusion: Pandemic months were initially associated with increased antibiotic prescribing which then fell below expected levels during the national lockdown. Findings are reassuring that antibiotic stewardship priorities have not been neglected due to COVID-19. Research is required into the effects of reduced RTI/UTI consultations on incidence of serious bacterial infection.