Study objectives: The aim of this study was to investigate the prognostic value of plasma d-dimer levels in patients with community-acquired pneumonia (CAP).
Design: Prospective observational study.
Setting: Hospital Lluis Alcanyis of Xativa, Spain.
Patients: Consecutive adult patients admitted to the hospital with CAP from January 2000 to October 2002.
Measurements and results: A total of 302 patients were included. Plasma d-dimer was measured using an automated latex assay. The relationships between plasma d-dimer and prognostic variables included in the pneumonia severity index (PSI) were examined using univariate and multivariate linear and logistic regression analyses. d-Dimer levels were negative (ie, < 500 ng/mL) in 16.9% of the patients. In nonsurvivors, the d-dimer plasma level mean value was 3,786 ng/mL, while in survivors it was 1,609 ng/mL (p < 0.0001). A significant relationship was found between the presence of elevated d-dimer levels and the PSI and APACHE (acute physiology and chronic health evaluation) II score. Elevated d-dimer levels were associated with radiologic pneumonia extension. The d-dimer predictive value for mechanical ventilation therapy showed an area under the curve of 0.78 (95% confidence interval, 0.71 to 0.81).
Conclusions: d-Dimer plasma levels could be useful for predicting clinical outcome in patients with CAP.