- Sascha Dublin, assistant investigator12,
- Michael L Jackson, EIS officer1,
- Jennifer C Nelson, associate investigator13,
- Noel S Weiss, professor2,
- Eric B Larson, executive director and senior investigator145,
- Lisa A Jackson, senior investigator12
- 1Group Health Center for Health Studies, 1730 Minor Avenue, Suite 1600, Seattle WA 98101-1448, USA
- 2Department of Epidemiology, University of Washington, Seattle, WA 98195
- 3Department of Biostatistics, University of Washington
- 4Department of Medicine, University of Washington
- 5Department of Health Services, University of Washington
- Correspondence to: S Dublin
- Accepted 31 January 2009
Objective To test the hypothesis that hydroxymethyl glutaryl coenzyme A reductase inhibitors (statins) may decrease the risk of community acquired pneumonia.
Design Population based case-control study.
Setting Group Health, a large integrated healthcare delivery system.
Population Immunocompetent, community dwelling Group Health members aged 65 to 94; two matched controls for each case with pneumonia. Information on comorbid illnesses and functional and cognitive status, potential confounders of the association between statin use and risk of pneumonia, came from medical record review and computerised pharmacy data.
Main outcome measure Adjusted estimates of risk of pneumonia in relation to current statin use.
Results 1125 validated cases of pneumonia and 2235 matched controls were identified. Compared with controls, cases were more likely to have chronic lung and heart disease, especially severe disease, and functional or cognitive impairment. Current statin use was present in 16.1% (181/1125) of cases and 14.6% (327/2235) of controls (adjusted odds ratio 1.26, 95% confidence interval 1.01 to 1.56). Among cases admitted to hospital and matched controls, current statin use was present in 17.2% (68/395) of cases and 14.2% (112/788) of controls (adjusted odds ratio 1.61, 1.08 to 2.39, compared with non-use). In people in whom statins were indicated for secondary prevention, the adjusted odds ratio for risk of pneumonia in relation to current statin use was 1.25 (0.94 to 1.67); in those with no such indication, it was 0.81 (0.46 to 1.42).
Conclusions Statin use was not associated with decreased risk of pneumonia among immunocompetent, community dwelling older people. Findings of previous studies may reflect “healthy user” bias.
We appreciate the assistance of Rod Walker, who did additional statistical analyses.
Contributors: SD, MLJ, JCN, NSW, and LAJ were involved in study conception and design and in acquisition of data. SD and MLJ were responsible for data analysis. All authors were involved in interpretation of results and in drafting or revising the manuscript. All authors approved the final submitted version. SD is the guarantor.
Funding: SD was funded by a Paul Beeson Career Development Award from the National Institute on Aging (grant K23AG028954). The Beeson award is also supported by the Hartford and Starr Foundations and Atlantic Philanthropies. Group Health Center for Health Studies internal funds covered the data collection and analysis. The sponsors played no role in study design; the collection, analysis or interpretation of data; the writing of the report; or in the decision to submit the manuscript for publication.
Competing interests: JCN has done consulting work for GlaxoSmithKline.
Ethical approval: All study procedures were approved by the Group Health Human Subjects Review Committee.
This is an open-access article distributed under the terms of the Creative Commons Attribution Non-commercial License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.