Application and comparison of scoring indices to predict outcomes in patients with healthcare-associated pneumonia

Abstract

Introduction: Healthcare-associated pneumonia (HCAP) is a relatively new category of pneumonia. It refers to infections that occur prior to hospital admission in patients with specific risk factors following contact or exposure to a healthcare environment. There is currently no scoring index to predict the outcomes of HCAP patients. We applied and compared different community acquired pneumonia (CAP) scoring indices to predict 30-day mortality and 3-day and 14-day intensive care unit (ICU) admission in patients with HCAP.

Methods: We conducted a retrospective cohort study based on an inpatient database from six medical centers, recruiting a total of 444 patients with HCAP between 1 January 2007 and 31 December 2007. Pneumonia severity scoring indices including PSI (pneumonia severity index), CURB 65 (confusion, urea, respiratory rate, blood pressure, age 65), IDSA/ATS (Infectious Diseases Society of America/American Thoracic Society), modified ATS rule, SCAP (severe community acquired pneumonia), SMART-COP (systolic blood pressure, multilobar involvement, albumin, respiratory rate, tachycardia, confusion, oxygenation, pH), SMRT-CO (systolic blood pressure, multilobar involvement, respiratory rate, tachycardia, confusion, oxygenation), and SOAR (systolic blood pressure, oxygenation, age, respiratory rate) were calculated for each patient. Patient characteristics, co-morbidities, pneumonia pathogen culture results, length of hospital stay (LOS), and length of ICU stay were also recorded.

Results: PSI (>90) has the highest sensitivity in predicting mortality, followed by CURB-65 (≥2) and SCAP (>9) (SCAP score (area under the curve (AUC): 0.71), PSI (AUC: 0.70) and CURB-65 (AUC: 0.66)). Compared to PSI, modified ATS, IDSA/ATS, SCAP, and SMART-COP were easy to calculate. For predicting ICU admission (Day 3 and Day 14), modified ATS (AUC: 0.84, 0.82), SMART-COP (AUC: 0.84, 0.82), SCAP (AUC: 0.82, 0.80) and IDSA/ATS (AUC: 0.80, 0.79) performed better (statistically significant difference) than PSI, CURB-65, SOAR and SMRT-CO.

Conclusions: The utility of the scoring indices for risk assessment in patients with healthcare-associated pneumonia shows that the scoring indices originally designed for CAP can be applied to HCAP.