Date Published: February 14, 2018
Publisher: Public Library of Science
Author(s): Ane Uranga, Jose M. Quintana, Urko Aguirre, Amaia Artaraz, Rosa Diez, Silvia Pascual, Aitor Ballaz, Pedro P. España, Oliver Schildgen.
Community-acquired pneumonia (CAP) is a major public health problem with high short- and long-term mortality. The main aim of this study was to develop and validate a specific prognostic index for one-year mortality in patients admitted for CAP.
This was an observational, prospective study of adults aged ≥18 years admitted to Galdakao-Usansolo Hospital (Bizkaia, Spain) from January 2001 to July 2009 with a diagnosis of CAP surviving the first 15 days. The entire cohort was divided into two parts, in order to develop a one-year mortality predictive model in the derivation cohort, before validation using the second cohort.
A total of 2351 patients were included and divided into a derivation and a validation cohort. After deaths within 15 days were excluded, one-year mortality was 10.63%. A predictive model was created in order to predict one-year mortality, with a weighted score that included: aged over 80 years (4 points), congestive heart failure (2 points), dementia (6 points), respiratory rate ≥30 breaths per minute (2 points) and blood urea nitrogen >30 mg/dL (3 points) as predictors of higher risk with C-index of 0.76. This new model showed better predictive ability than current risk scores, PSI, CURB65 and SCAP with C-index of 0.73, 0.69 and 0.70, respectively.
An easy-to-use score, called the one-year CAPSI, may be useful for identifying patients with a high probability of dying after an episode of CAP.
Community-acquired pneumonia (CAP) is a major public health problem with high morbidity and mortality . The annual incidence ranges between two and eight cases per thousand inhabitants —together with influenza, it was the seventh cause of mortality in the United States in 2008 . Short-term mortality rates are high in patients admitted for CAP, but are even higher in those admitted to intensive care units, and up to 50% if there is a need for vasopressors . Long-term mortality also remains high, with rates of 8%, 21%, and 36% within 90 days, one year, and five years, respectively .
A total of 2351 patients, with 1208 and 1143 in the derivation and validation cohorts, respectively, were included. Baseline characteristics are shown in S1 Table. The mean age (SD) of the entire cohort was 69 (16.58) years, with 784 (33.35%) patients ≥80 years old. Both cohorts were similar except for the chronic obstructive pulmonary disease (COPD) rate, which was higher in the validation cohort. In total, 208 (7.99%) patients died during hospitalization, while 251 patients died within 15 days of diagnosis. After deaths within 15 days were excluded, one-year mortality was 10.84% (131 patients) and 10.41% (119 patients) in the derivation and validation cohorts, respectively (p = 0.74). Table 1 shows baseline characteristics among survivors and non-survivors at one-year.
This study shows that long-term mortality in hospitalized patients with CAP is high. An easy-to-use score with five variables can help physicians identify those patients with CAP at high risk of death within one year of an index admission. A weighted score, called the one-year CAPSI, constructed by age ≥80, CHF, dementia, BUN >30 mg/dL and RR ≥30 breaths/min can predict one-year mortality with high predictive accuracy. Indeed, one-year CAPSI showed significantly better predictive accuracy than CURB65 and SCAP.
An easy-to-use score, one-year CAPSI, based on five parameters can predict one-year mortality with high predictive accuracy, better than widely known severity scores. Recognizing these five variables may be useful for identifying patients with a high probability of dying after an episode of CAP. Future research should be conducted to clarify the impact of inflammation on CAP prognosis.