Safety of reduced antibiotic prescribing for self limiting respiratory tract infections in primary care: cohort study using electronic health recordsBMJ 2016; 354 doi: https://doi.org/10.1136/bmj.i3410 (Published 04 July 2016) Cite this as: BMJ 2016;354:i3410
- Martin C Gulliford, professor of public health1,
- Michael V Moore, professor of primary healthcare research2,
- Paul Little, professor of primary care research2,
- Alastair D Hay, professor of primary care3,
- Robin Fox, general practitioner4,
- A Toby Prevost, professor of medical statistics1,
- Dorota Juszczyk, research associate1,
- Judith Charlton, research associate1,
- Mark Ashworth, reader in general practice1
- 1Department of Primary Care and Public Health Sciences, King’s College London, Guy’s Campus, London SE1 1UL, UK
- 2Academic Unit for Primary Care and Population Sciences, University of Southampton, Southampton, UK
- 3Centre for Academic Primary Care, School of Social and Community Medicine, University of Bristol, Bristol, UK
- 4The Health Centre, Bicester, Oxford, UK
- Correspondence to: M C Gulliford
- Accepted 7 June 2016
Objective To determine whether the incidence of pneumonia, peritonsillar abscess, mastoiditis, empyema, meningitis, intracranial abscess, and Lemierre’s syndrome is higher in general practices that prescribe fewer antibiotics for self limiting respiratory tract infections (RTIs).
Design Cohort study.
Setting 610 UK general practices from the UK Clinical Practice Research Datalink.
Participants Registered patients with 45.5 million person years of follow-up from 2005 to 2014.
Exposures Standardised proportion of RTI consultations with antibiotics prescribed for each general practice, and rate of antibiotic prescriptions for RTIs per 1000 registered patients.
Main outcome measures Incidence of pneumonia, peritonsillar abscess, mastoiditis, empyema, meningitis, intracranial abscess, and Lemierre’s syndrome, adjusting for age group, sex, region, deprivation fifth, RTI consultation rate, and general practice.
Results From 2005 to 2014 the proportion of RTI consultations with antibiotics prescribed decreased from 53.9% to 50.5% in men and from 54.5% to 51.5% in women. From 2005 to 2014, new episodes of meningitis, mastoiditis, and peritonsillar abscess decreased annually by 5.3%, 4.6%, and 1.0%, respectively, whereas new episodes of pneumonia increased by 0.4%. Age and sex standardised incidences for pneumonia and peritonsillar abscess were higher for practices in the lowest fourth of antibiotic prescribing compared with the highest fourth. The adjusted relative risk increases for a 10% reduction in antibiotic prescribing were 12.8% (95% confidence interval 7.8% to 17.5%, P<0.001) for pneumonia and 9.9% (5.6% to 14.0%, P<0.001) for peritonsillar abscess. If a general practice with an average list size of 7000 patients reduces the proportion of RTI consultations with antibiotics prescribed by 10%, then it might observe 1.1 (95% confidence interval 0.6 to 1.5) more cases of pneumonia each year and 0.9 (0.5 to 1.3) more cases of peritonsillar abscess each decade. Mastoiditis, empyema, meningitis, intracranial abscess, and Lemierre’s syndrome were similar in frequency at low prescribing and high prescribing practices.
Conclusions General practices that adopt a policy to reduce antibiotic prescribing for RTIs might expect a slight increase in the incidence of treatable pneumonia and peritonsillar abscess. No increase is likely in mastoiditis, empyema, bacterial meningitis, intracranial abscess, or Lemierre’s syndrome. Even a substantial reduction in antibiotic prescribing was predicted to be associated with only a small increase in numbers of cases observed overall, but caution might be required in subgroups at higher risk of pneumonia.
Contributors: MCG, MVM, PL, ADH, RF, DJ, and MA contributed to the idea and design of the study. MCG analysed the data. JC checked and replicated the analysis. ATP advised on statistical analysis. MCG drafted the paper. All authors contributed to and approved the final draft. MCG is guarantor.
Funding: The research was supported by the UK National Institute for Health Research Health Technology Assessment programme initiative on antimicrobial drug resistance. The funders did not engage in the design and conduct of the study; collection, management, analysis, and interpretation of the data; or preparation, review, and approval of the manuscript. MCG and ATP were also supported by the National Institute of Health Research (NIHR) Biomedical Research Centre at Guy’s and St Thomas’ Hospitals. The views expressed are those of the author(s) and not necessarily those of the National Health Service, the NIHR, or the Department of Health. This study is based in part on data from the Clinical Practice Research Datalink obtained under licence from the UK Medicines and Healthcare products Regulatory Agency. However, the interpretation and conclusions contained in this report are those of the authors alone.
Competing interests: All authors have completed the ICMJE uniform disclosure form at www.icmje.org/coi_disclosure.pdf and declare: no support from any organisation for the submitted work; no financial relationships with any organisations that might have an interest in the submitted work in the previous three years; no other relationships or activities that could appear to have influenced the submitted work.
Ethical approval: The protocol for the study was approved by the Clinical Practice Research Datalink (CPRD) independent scientific advisory committee, reference 14_130A2. The CPRD has broad National Research Ethics Service Committee ethics approval for observational research studies. The research was conducted to inform a study funded by the NIHR Health Technology Assessment programme. The outcomes were selected from a wider range of safety outcomes proposed for the study because they were identified as being potentially associated with respiratory tract infections.
Data sharing: CPRD data were analysed under licence and are not available for sharing.
Transparency: The guarantor (MCG) affirms that the manuscript is an honest, accurate, and transparent account of the study being reported; that no important aspects of the study have been omitted; and that any discrepancies from the study as planned (and, if relevant, registered) have been explained.
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