Effect of statin treatment on short term mortality after pneumonia episode: cohort studyBMJ 2011; 342 doi: https://doi.org/10.1136/bmj.d1642 (Published 06 April 2011) Cite this as: BMJ 2011;342:d1642
- Ian Douglas, lecturer in epidemiology,
- Stephen Evans, professor of pharmacoepidemiology,
- Liam Smeeth, professor of clinical epidemiology
- 1Faculty of Epidemiology and Population Health, London School of Hygiene and Tropical Medicine, London WC1E 7HT, UK
- Correspondence to: I Douglas
- Accepted 21 February 2011
Objective To determine whether statins protect against all cause mortality after a diagnosis of pneumonia.
Design Cohort study using propensity score based method to control for differences between people prescribed and not prescribed statins.
Setting United Kingdom Health Improvement Network database, which contains electronic primary care medical records of more than six million patients.
Participants Every patient starting a statin between 1995 and 2006 (129 288) matched with up to five non-statin users (n=600 241); 9073 patients had a recorded diagnosis of pneumonia, of whom 1398 were using a statin.
Main outcome measure All cause mortality within six months of diagnosis of pneumonia.
Results Among users and non-users of statins with comparable propensity scores, 95/942 users and 686/3615 non-users died on the day that pneumonia was diagnosed. In the following six month period, 109/847 statin users died compared with 578/2927 non-users, giving an adjusted hazard ratio of 0.67 (0.49 to 0.91). If these observed benefits translated into clinical practice, 15 patients would need to be treated with a statin for six months after pneumonia to prevent one death.
Conclusions Compared with people who were not taking statins, the risk of dying in the six month period after pneumonia was substantially lower among people who were already established on long term statin treatment when the pneumonia occurred. Whether some or all of this protective effect would be obtained if statin treatment begins when a patient first develops pneumonia is not known. However, given that statins are cheap, safe, and well tolerated, a clinical trial in which people with pneumonia are randomised to a short period of statin treatment is warranted.
We thank EPIC for supplying the data and all the general practices that participate in the THIN database.
Contributors: ID and LS were responsible for the conception and design of the study. ID had principal responsibility for analysis, drafting and revising the manuscript, and final approval. LS and SE contributed to the analysis and the drafting, revision, and final approval of the manuscript. All authors were responsible for interpretation of the data. ID is the guarantor.
Funding: During this work, ID was funded by grants from the Wellcome Trust and the Medical Research Council paid to the London School of Hygiene and Tropical Medicine. LS was funded by a grant from the Wellcome Trust. Sponsors played no role in the study design; the collection, analysis, and interpretation of data; the writing of the article; or the decision to submit it for publication
Competing interests: All authors have completed the Unified Competing Interest form at www.icmje.org/coi_disclosure.pdf (available on request from the corresponding author) and declare that (1) they have no relationships with companies that might have an interest in the submitted work in the previous three years; (2) their spouses, partners, or children have no financial relationships that may be relevant to the submitted work; and (3) they have no non-financial interests that may be relevant to the submitted work.
Ethical approval: The South Thames Multi-centre Research Ethics Committee and the London School of Hygiene and Tropical Medicine Ethics Committee approved the study.
Data sharing: No additional data available.
This is an open-access article distributed under the terms of the Creative Commons Attribution Non-commercial License, which permits use, distribution, and reproduction in any medium, provided the original work is properly cited, the use is non commercial and is otherwise in compliance with the license. See: http://creativecommons.org/licenses/by-nc/2.0/ and http://creativecommons.org/licenses/by-nc/2.0/legalcode.