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Download Thesis This electronic thesis or dissertation has been downloaded from the King’s Research Portal at https://kclpure.kcl.ac.uk/portal/ Antibiotics Prescribing by General Practitioners for Urinary Tract Infections in Elderly Patients Alomar, Hussain Abdulrahman Awarding institution: King's College London The copyright of this thesis rests with the author and no quotation from it or information derived from it may be published without proper acknowledgement. END USER LICENCE AGREEMENT Unless another licence is stated on the immediately following page this work is licensed under a Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International licence. https://creativecommons.org/licenses/by-nc-nd/4.0/ You are free to copy, distribute and transmit the work Under the following conditions: Attribution: You must attribute the work in the manner specified by the author (but not in any way that suggests that they endorse you or your use of the work). Non Commercial: You may not use this work for commercial purposes. No Derivative Works - You may not alter, transform, or build upon this work. Any of these conditions can be waived if you receive permission from the author. Your fair dealings and other rights are in no way affected by the above. Take down policy If you believe that this document breaches copyright please contact [email protected] providing details, and we will remove access to the work immediately and investigate your claim. Download date: 30. Sep. 2021 Antibiotics Prescribing by General Practitioners for Urinary Tract Infections in Elderly Patients by Hussain Abdulrahman Alomar A thesis submitted in partial fulfilment of the requirements of King’s College London for the degree of Doctor of Philosophy September, 2016 Abstract Abstract Urinary tract infections (UTIs) are the second most common infection seen by general practitioners (GPs) in the elderly. UTIs in the elderly can lead to serious complications with increased risk of mortality, yet there are no national or international dedicated guidelines for antibiotic treatment in this patient group. The epidemiology of UTIs in the United Kingdom (UK) for the elderly population and GPs’ antibiotics prescribing for this condition have received little or no attention. This thesis describes GPs’ antibiotics prescribing for UTIs in elderly patients in the UK by exploring the prevalence of UTIs in elderly patients, auditing GPs’ antibiotics prescribing, explaining the variations in GPs’ views and perceptions and identifying the factors that may influence or affect GPs’ antibiotics prescribing using a mixed methods approach. To achieve research aim, a comprehensive explanatory sequential mixed methods approach was undertaken. The initial research was quantitative and took the form of a retrospective, cross-sectional, drug utilisation study that included elderly patients’ data retrieved from electronics medical records, namely, Disease Analyzer (IMS-DA), for the period between 1 January 2010 and 31 December 2012. The subsequent research was qualitative and took a phenomenographic approach with two analytical techniques: phenomenographic analysis and thematic analysis, with data collected through semi- structured interviews with 17 GPs. The results from the quantitative study identified 77,290 UTI visits by 21,150 elderly patients, of whom 77.42% (N = 16,375) received at least one antibiotic prescription per visit over the study period. The mean age and sex adjusted UTI prevalence was found to be 23.35 (95% CI 21.84-24.85) per 1,000 person-years for year 2010, 21.44 (95% CI 19.99-22.88) per 1,000 person-years for year 2011 and 17.88 (95% CI 16.56-19.19) per 1,000 person-years. The total number of issued antibiotics prescriptions for UTIs during the study period was 37,815. Adherence results showed that 9,125 (24.1%) broad- spectrum antibiotics prescriptions were issued for elderly patients, including ciprofloxacin (N = 1,733; 4.6%), co-amoxiclav (N = 2,350; 6.2%) and cephalexin (N = 5,042; 13.3%). Additionally, 32.2% (N = 12,159) of antibiotics prescriptions were prescribed for durations other than those recommended either for treatment or for prophylaxis; this was seen in 10,605 (33%) female patients’ UTI antibiotics prescriptions and 1,554 (27.5%) male patients’ UTI antibiotics prescriptions. The findings from the qualitative study identified five distinct categories of description representing the ways in which GPs perceive antibiotics prescribing in elderly patients with UTIs. These categories are perceptions, knowledge, decision, practice and approach. Moreover, GPs’ knowledge and perceptions about antibiotics were found to be shaped through seven external horizons: undergraduate education, postgraduate training, personal experience, interaction with peers, interaction and influence of patients’ expectations, the healthcare system, and availability of guidelines and evidence. Additionally, the thematic analysis revealed 29 factors that may influence GPs’ antibiotics prescribing for UTIs including: GPs’ personal experience and familiarity with specific antibiotics, GPs’ education, knowledge and training, complacency, GPs’ fear, responsibility of other healthcare professionals, GPs’ awareness about antibiotic resistance threat, GPs’ awareness about 2 Abstract microbial resistance results and information GPs’ awareness about local resistance pattern, GPs’ antibiotic prescribing concerns, diagnosis and clinical decision making by GPs’, GPs’ ethos and ethical values, patient’s age and gender, patient’s medical history and clinical characteristics, patient’s social situation and living conditions, patient’s level of understanding and knowledge, patient’s desire for a quick fix, patient’s autonomy, visits and education by prescribing advisors, audit, monitoring and feedback of prescribing, influence by secondary care doctor prescribing practice, implementation of local policies, guidance and formulary, time, guidelines and evidence, antibiotics shortage, incentives, media, cost, healthcare resources and constraints, pharmaceutical companies, over-prescribing and society experience and expectation. In conclusion, the findings from the mixed methods research confirmed that some GPs in the UK are less likely to adhere to available good practice points for the management of UTIs in elderly patients, that there are variations among GPs’ views and perceptions about antibiotics and that GPs’ antibiotics prescribing practice is influenced by various factors such as guidelines, complacency, clinical presentation, resistance, and audit and feedback. The results highlight the need to optimise and rationalise GPs’ antibiotics prescribing in the elderly by developing robust guidelines synthesised specifically for the elderly population based on studies and evidence from literature designed for elderly patients, to increase GPs’ awareness of and familiarity with guidelines, to increase their uptake and involve GPs in the process of evidence synthesis because of their knowledge of the context of general practice. There is also a need to implement a multifaceted intensive approach with the aim of minimising variations in GPs’ views for AMR and approaching elderly patients, modifying GPs’ antibiotics perceptions and determining whether they will change their practice, correcting some GPs’ misperceptions such as patients’ expectations of antibiotics and patients’ satisfaction through encouraging communication and targeting the GPs’ seven external horizons through multifaceted educational programmes. 3 Table of Contents Table of Contents Chapter 1 Introduction ............................................................................................. 18 1.1 Introduction .......................................................................................................... 18 1.2 UK Primary Care and the GP Workforce ............................................................... 18 Definitions and Responsibilities .................................................................. 18 GPs Workforce in the UK............................................................................ 19 1.3 Antibiotics ............................................................................................................ 20 Historical Overview .................................................................................... 21 Current Overview ........................................................................................ 24 Antibiotics Classification............................................................................. 24 Antibiotics Use and Resistance .................................................................... 25 Inappropriate Antibiotic Prescribing in Primary Care .................................. 28 GPs’ Antibiotics Prescribing Behaviour....................................................... 32 Antibiotics Consumption in UK Primary Care ............................................. 37 1.4 Ageing and the Elderly .......................................................................................... 44 An Ageing and Elderly Population .............................................................. 44 Changes Associated with Ageing................................................................. 47 Infections in the Elderly .............................................................................. 48 Special Considerations in Antibiotics Prescribing: An Elderly Perspective .. 49 1.5 UTIs in the Elderly ...............................................................................................
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