Predicting mortality in the elderly with community-acquired pneumonia: should we design a new car or set a new 'speed limit'?

Community-acquired pneumonia (CAP) is a common illness associated with increasing mortality rates that parallel the site of care. While outpatients have a risk of dying of <5%, those in hospital have a mortality rate of 12% and those managed in the ICU can have a chance of dying that exceeds 30%.1 In addition, delayed recognition of severe illness can add to mortality, with those admitted to the ICU late in the course of disease having a higher mortality than those admitted early.2 Thus, patient outcome is dependent on making an accurate assessment about where patients should be initially managed and the intensity of care that they should receive. To this end, a number of prognostic scoring systems have been developed for patients with CAP that can predict the mortality risk, which is then often applied as a surrogate for deciding the initial site of care.1 3 4 Unfortunately, the risk of death is not always correlated with the need for a high level of care including need for ICU admission. In fact, patients who are young and otherwise healthy may benefit from ICU admission yet have a much lower predicted mortality risk than older patients with multiple medical comorbidities who may benefit little from admission to a hospital unit that provides a high level of care. Accurate definition of the site of care not only impacts mortality, but also the cost of care which rises incrementally from outpatient to inpatient to ICU management. The most commonly used tools for predicting mortality—the CURB-65 (confusion, elevated blood urea nitrogen, elevated respiratory rate, low blood pressure and age >65 years), derived from the British Thoracic Society rule,5 and the Pneumonia Severity Index (PSI)1—predict mortality by giving a point …