Performances of prognostic scoring systems in patients with healthcare-associated pneumonia.

Background: There are limited data on the performance of the pneumonia severity index (PSI) and CURB-65 (confusion, urea, respiratory rate, blood pressure, age ≥65) score, which were originally developed for community-acquired pneumonia (CAP), for patients with healthcare-associated pneumonia (HCAP).

Methods: The performances of PSI and CURB-65 were retrospectively evaluated in patients with HCAP compared to patients with CAP using prospectively collected data between January 2008 and December 2010.

Results: In total, 938 patients hospitalized with pneumonia were eligible for this study, consisting of 519 (55%) with CAP and 419 (45%) with HCAP. The PSI and CURB-65 scores had similar trends of increasing mortality with worsening risk class in both the HCAP and CAP groups. In the HCAP group, however, the low-risk patients identified using CURB-65 had a higher aggregate 30-day mortality compared with the low-risk patients identified using PSI. Although the performances of PSI and CURB-65 in the HCAP group showed similar trends to those observed in the CAP group, the estimated areas under the receiver operating characteristic curve for PSI (0.679, 95% confidence interval [CI], .619-.739) and CURB-65 (0.599, 95% CI, .522-.675) in the HCAP group were significantly lower than those in the CAP group (0.835, 95% CI, .768-.759 for PSI and .686-.832 for CURB-65).

Conclusions: The performances of PSI and CURB-65 for predicting 30-day mortality in patients with HCAP were comparable to those in patients with CAP. However, the discriminatory powers of PSI and CURB-65 for 30-day mortality were significantly lower in the HACP group than those in the CAP group.