Abstract
Some patients classified as having non-severe community-acquired pneumonia (CAP) by CURB-65 subsequently die. The objective of this study was to identify risk factors for mortality in non-severe patients and to test how risk factors might be used. Patients who had a CURB-65 score of 0–2 on admission to hospital and were alive at 30 days were compared with those who died. Identified risk factors were included in new variations of CURB-65 and new management strategies. Age >65 years, blood urea >7 mmol/l, bilateral/multi-lobar appearance of the chest radiograph (CXR), social situation (living alone/no fixed abode or residential/nursing care) and temperature <36°C were associated with mortality (p < 0.05). A two-step approach, with initial use of CURB-65 followed by the above non-CURB-65 criteria, increased the proportion of patients correctly classified as having severe CAP who subsequently died from 54/76 (71%, 95% confidence interval [CI] 61% to 81%) to 72/76 (95%, 95% CI 90% to 100%). The consideration of additional risk factors in a two-step approach can improve the stratification of mortality by CURB-65. Physicians should be cautious about managing patients with CAP as outpatients if they have a CURB-65 score of 1 (or more) and have at least one of the three additional risk factors identified.
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DR has no conflict of interests. DN has served on Advisory Boards for Janssen Cilag (UK Anti-Infectives), Wyeth (UK tigecycline), Novartis (UK daptomycin), Optimer (Global, Optima-80) and received honoraria for speaking from Novartis, Johnson & Johnson, Pfizer and Wyeth. PD has served on Advisory Boards for Johnson and Johnson (Global Anti-Infectives) and Wyeth (UK tigecycline), received honoraria for speaking from Johnson & Johnson, Optimer, Pfizer, Wyeth and received research funding from Boehringer Ingelheim, GlaxoSmithKline and Pfizer. GB has received support to attend conferences/meetings from Sanofi-Aventis, Gilead, Pfizer, Chiron and Janssen Cilag, received honoraria for speaking/DVD development from Sanofi-Aventis and served on an advisory board for Wyeth (UK tigecycline).
Contributors
DR analysed and interpreted the data, and wrote the first draft of the manuscript. PD and DN were involved in developing the initial idea, interpreting the data and edited the second draft of the manuscript. GB had the initial study idea, collected and analysed the data, and edited the first draft of the manuscript. GB is the guarantor and had full access to all of the data in the study, and takes responsibility for the integrity of the data and the accuracy of the data analysis.
Funding
The original quality improvement project was funded by NHS Education Scotland and The Chief Scientist Office, Scotland.
Ethical approval
The collection of data was approved by both Tayside University Hospitals NHS Trust’s medical ethics committee and Caldicot Guardian.
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Ronan, D., Nathwani, D., Davey, P. et al. Predicting mortality in patients with community-acquired pneumonia and low CURB-65 scores. Eur J Clin Microbiol Infect Dis 29, 1117–1124 (2010). https://doi.org/10.1007/s10096-010-0970-7
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DOI: https://doi.org/10.1007/s10096-010-0970-7