An evaluation of antibiotic prescribing trends and their impact on infection-related complications in primary- and secondary care in the UK

Abstract

The majority of antibiotics (approximately 80%) are prescribed by general practitioners (GPs) in the UK. Reducing inappropriate antibiotic prescribing is an important aim of antibiotic stewardship programmes (ASP) in order to maintain the efficacy of existing antibiotics for future generations. Analysis of longitudinal data from research databases in the UK including CPRD, SAIL Databank, and NHS digital open prescribing, can provide an insight into the effectiveness of current interventions, reports and guidelines aimed at reducing inappropriate prescribing. The aim of this thesis was to evaluate factors influencing antibiotic prescribing in primary care in the UK at patient- and practice level. Broadly, three research questions were considered: (1) To what extent does varying antibiotic prescribing for common infections influence infection-related complications? (2) Are patient characteristics and risk factors being used to inform antibiotic prescribing? (3) Are there any consistent antibiotic prescribing trends among English GPs and what factors influence this? Chapter 2 found the effect of physician preference antibiotic prescribing on the risk of infection-related complications among antibiotic users compared with non-antibiotics users. Chapter 3 demonstrates an inverse association between lower levels of practice level antibiotic prescribing for common infections and higher rates of infection-related complications by comparing high and low prescribing GP practices. In Chapter 4, this association was further explored and showed a large variability in absolute risk reductions for patients with an incidental common infection and an independence of predicted risk with GPs propensity to prescribe antibiotics. While Chapters 2 – 4 present the effect of antibiotic prescribing on infection-related complications for patients in primary care (RQ1/RQ2). These analyses do not provide insight into antibiotic changes through time and the potential of identifying GP practices for targeted antibiotic guidance. Thus, Chapter 5 explored the complex heterogeneity of antibiotic prescribing trends among English GPs and identified seven clusters with similar prescribing trends over time, which were not associated with deprivation scores (RQ3). Notable changes in prescribing trend were detected in early 2015, mid 2016, and late 2017. This thesis has the potential to improve understanding of the potential effects of reduced antibiotic prescribing in primary care and inform the implementation of more targeted identification of GPs and patients who will benefit most from a fundamental change in antibiotic prescribing behaviour.

Date of Award	31 Dec 2021
Original language	English
Awarding Institution	The University of Manchester
Supervisor	Victoria Palin (Supervisor), Matthew Sperrin (Supervisor) & Tjeerd Van Staa (Supervisor)