Microbiological and Clinical Significance of Prior Hospitalization in Patients Admitted With Community-Onset Pneumonia: A Propensity Score Matching Study

Abstract

SESSION TITLE: Chest Infections SESSION TYPE: Original Investigation Poster PRESENTED ON: Wednesday, November 1, 2017 at 01:30 PM - 02:30 PM PURPOSE: Patients who have had prior hospitalization (PH) for two or more days within the past 90 days have been included as a category of healthcare associated pneumonia. Although PH has been considered as a risk factor for infection with potentially drug-resistant (PDR) pathogens in patients with community-onset (CO) pneumonia, the evidence is limited. We aimed to elucidate the clinical impact of PH on these patients. METHODS: This retrospective observational cohort study with prospectively collected data was conducted at Jeju National University Hospital between January 2012 and December 2014. According to the incidence of hospitalization for more than two days prior to the hospital visit of interest, we classified the study patients into PH-associated pneumonia (PHAP) and community-acquired pneumonia (CAP) groups. Propensity scores were constructed to improve the balance of baseline characteristics between two groups, and the clinical outcomes were compared. We also conducted subgroup analyses based on prior antibiotic use, duration of PH, and time to re-admission. RESULTS: A total of 704 patients were identified; the PHAP group included 97 patients (13.7%). Patients with PHAP had more comorbidities than those with CAP. And the median CURB-65 and PSI scores were higher in patients with PHAP than in those with CAP. After matching according to propensity scores, the baseline characteristics of the PHAP group were similar to those of the CAP group. The isolation rate of PDR pathogens as well as the 30-day and total in-hospital mortality did not differ between the PHAP and propensity score-matched CAP patients (14.4% vs. 9.2%, p=0.267; 13.4% vs. 13.4%, P = 1.000; and 17.5% vs. 14.4%, P = 0.557, respectively). In subgroup analyses, PHAP patients with prior antibiotic use or duration of PH > 10 days showed significantly higher isolation rates of PDR pathogens. Multivariate logistic regression analysis demonstrated that prior antibiotic use was associated with the isolation rate of PDR pathogens (adjusted OR: 5.066; 95% CI: 1.231-20.845). CONCLUSIONS: PH itself might not be related with higher isolation rates of PDR pathogens or mortality in patients with CO-pneumonia. Because PHAP patients had primarily worse host-related factors associated with pneumonia, they seemed to have poorer clinical outcomes. The independent risk factor for the isolation of PDR pathogens was prior antibiotic use in patients with PHAP. CLINICAL IMPLICATIONS: It seems reasonable that broad spectrum antibiotic therapy for PDR pathogens should be selectively applied to PHAP patients with prior antibiotic use. DISCLOSURE: The following authors have nothing to disclose: Jonghoo Lee, Yee Hyung Kim No Product/Research Disclosure Information