The University of Southampton
University of Southampton Institutional Repository

Amoxicillin for acute lower respiratory tract infection in primary care: subgroup analysis of potential high-risk groups

Amoxicillin for acute lower respiratory tract infection in primary care: subgroup analysis of potential high-risk groups
Amoxicillin for acute lower respiratory tract infection in primary care: subgroup analysis of potential high-risk groups
Background: Antibiotics are of limited overall clinical benefit for uncomplicated lower respiratory tract infection (LRTI) but there is uncertainty about their effectiveness for patients with features associated with higher levels of antibiotic prescribing.

Aim: To estimate the benefits and harms of antibiotics for acute LRTI among those producing coloured sputum, smokers, those with fever or prior comorbidities, and longer duration of prior illness.

Design and setting: Secondary analysis of a randomised controlled trial of antibiotic placebo for acute LRTI in primary care.

Method: Two thousand and sixty-one adults with acute LRTI, where pneumonia was not suspected clinically, were given amoxicillin or matching placebo. The duration of symptoms, rated moderately bad or worse (primary outcome), symptom severity on days 2–4 (0–6 scale), and the development of new or worsening symptoms were analysed in pre-specified subgroups of interest. Evidence of differential treatment effectiveness was assessed in prespecified subgroups by interaction terms.

Results: No subgroups were identified that were significantly more likely to benefit from antibiotics in terms of symptom duration or the development of new or worsening symptoms. Those with a history of significant comorbidities experienced a significantly greater reduction in symptom severity between days 2 and 4 (interaction term ?0.28, P = 0.003; estimated effect of antibiotics among those with a past history ?0.28 [95% confidence interval = ?0.44 to ?0.11], P = 0.001), equivalent to three people in 10 rating symptoms as a slight rather than a moderately bad problem. For subgroups not specified in advance antibiotics provided a modest reduction in symptom severity for non-smokers and for those with short prior illness duration (<7 days), and a modest reduction in symptom duration for those with short prior illness duration.

Conclusion: There is no clear evidence of clinically meaningful benefit from antibiotics in the studied high-risk groups of patients presenting in general practice with uncomplicated LRTIs where prescribing is highest. Any possible benefit must be balanced against the side-effects and longer-term effects on antibiotic resistance.
antibiotics, primary health care, randomised controlled trial, respiratory infections
0960-1643
e75-e80
Moore, Michael
1be81dad-7120-45f0-bbed-f3b0cc0cfe99
Stuart, Beth
626862fc-892b-4f6d-9cbb-7a8d7172b209
Coenen, Samuel
3d0dc4e0-e5ba-4d66-ba92-15900ccc551e
Butler, Chris C.
cedab343-9e0c-420f-ba80-f2f824969687
Goossens, Herman
31f8e1ae-7da0-473c-bd49-f911c2187451
Verheij, Theo J.M.
817a26b8-7db9-4e79-b00e-c0457f19f236
Little, Paul
1bf2d1f7-200c-47a5-ab16-fe5a8756a777
Moore, Michael
1be81dad-7120-45f0-bbed-f3b0cc0cfe99
Stuart, Beth
626862fc-892b-4f6d-9cbb-7a8d7172b209
Coenen, Samuel
3d0dc4e0-e5ba-4d66-ba92-15900ccc551e
Butler, Chris C.
cedab343-9e0c-420f-ba80-f2f824969687
Goossens, Herman
31f8e1ae-7da0-473c-bd49-f911c2187451
Verheij, Theo J.M.
817a26b8-7db9-4e79-b00e-c0457f19f236
Little, Paul
1bf2d1f7-200c-47a5-ab16-fe5a8756a777

Moore, Michael, Stuart, Beth, Coenen, Samuel, Butler, Chris C., Goossens, Herman, Verheij, Theo J.M. and Little, Paul (2014) Amoxicillin for acute lower respiratory tract infection in primary care: subgroup analysis of potential high-risk groups. British Journal of General Practice, 64 (619), e75-e80. (doi:10.3399/bjgp14X677121). (PMID:24567620)

Record type: Article

Abstract

Background: Antibiotics are of limited overall clinical benefit for uncomplicated lower respiratory tract infection (LRTI) but there is uncertainty about their effectiveness for patients with features associated with higher levels of antibiotic prescribing.

Aim: To estimate the benefits and harms of antibiotics for acute LRTI among those producing coloured sputum, smokers, those with fever or prior comorbidities, and longer duration of prior illness.

Design and setting: Secondary analysis of a randomised controlled trial of antibiotic placebo for acute LRTI in primary care.

Method: Two thousand and sixty-one adults with acute LRTI, where pneumonia was not suspected clinically, were given amoxicillin or matching placebo. The duration of symptoms, rated moderately bad or worse (primary outcome), symptom severity on days 2–4 (0–6 scale), and the development of new or worsening symptoms were analysed in pre-specified subgroups of interest. Evidence of differential treatment effectiveness was assessed in prespecified subgroups by interaction terms.

Results: No subgroups were identified that were significantly more likely to benefit from antibiotics in terms of symptom duration or the development of new or worsening symptoms. Those with a history of significant comorbidities experienced a significantly greater reduction in symptom severity between days 2 and 4 (interaction term ?0.28, P = 0.003; estimated effect of antibiotics among those with a past history ?0.28 [95% confidence interval = ?0.44 to ?0.11], P = 0.001), equivalent to three people in 10 rating symptoms as a slight rather than a moderately bad problem. For subgroups not specified in advance antibiotics provided a modest reduction in symptom severity for non-smokers and for those with short prior illness duration (<7 days), and a modest reduction in symptom duration for those with short prior illness duration.

Conclusion: There is no clear evidence of clinically meaningful benefit from antibiotics in the studied high-risk groups of patients presenting in general practice with uncomplicated LRTIs where prescribing is highest. Any possible benefit must be balanced against the side-effects and longer-term effects on antibiotic resistance.

Text
bjgpfeb2014-64-619-e75_new.pdf - Version of Record
Restricted to Repository staff only
Request a copy

More information

e-pub ahead of print date: 27 January 2014
Published date: 1 February 2014
Keywords: antibiotics, primary health care, randomised controlled trial, respiratory infections
Organisations: Primary Care & Population Sciences

Identifiers

Local EPrints ID: 363366
URI: https://eprints.soton.ac.uk/id/eprint/363366
ISSN: 0960-1643
PURE UUID: c664d99d-60ad-41d2-a2b1-de2d44a174a7
ORCID for Michael Moore: ORCID iD orcid.org/0000-0002-5127-4509

Catalogue record

Date deposited: 24 Mar 2014 16:37
Last modified: 01 Oct 2019 00:49

Export record

Altmetrics

Contributors

Author: Michael Moore ORCID iD
Author: Beth Stuart
Author: Samuel Coenen
Author: Chris C. Butler
Author: Herman Goossens
Author: Theo J.M. Verheij
Author: Paul Little

University divisions

Download statistics

Downloads from ePrints over the past year. Other digital versions may also be available to download e.g. from the publisher's website.

View more statistics

Atom RSS 1.0 RSS 2.0

Contact ePrints Soton: eprints@soton.ac.uk

ePrints Soton supports OAI 2.0 with a base URL of https://eprints.soton.ac.uk/cgi/oai2

This repository has been built using EPrints software, developed at the University of Southampton, but available to everyone to use.

We use cookies to ensure that we give you the best experience on our website. If you continue without changing your settings, we will assume that you are happy to receive cookies on the University of Southampton website.

×