1501. Risk Factors for Clostridium difficile Infection in Patients Hospitalized with Community-Acquired Pneumonia

BACKGROUND: Patients with community-acquired pneumonia (CAP) are often prescribed broad-spectrum antibiotics, putting them at risk for developing Clostridium difficile infection (CDI). Previous studies of risk factors for CDI in this population have suffered from small sample sizes. We examined the risk factors for CDI in patients hospitalized with CAP using a large US database. METHODS: We included adult patients admitted with CAP 2010–2015 to 175 US hospitals participating in Premier and providing administrative and microbiological data. Patients were identified as having CAP if they had a diagnosis of pneumonia, a chest radiograph, and were treated with antimicrobials on day 1 and for ≥3 days. Incident CDI was identified with ICD-9 diagnosis code (not present on admission) and a positive laboratory test. We used descriptive statistics and mixed multiple logistic regression modeling to mutually adjust and evaluate risk factors previously suggested in the CDI literature. RESULTS: Among 148,417 inpatients with pneumonia treated with antibiotics, 789 (0.53%) developed CDI. The median age was 75 years, and 53% were female. Compared with patients with no CDI, those with CDI were older (75 vs. 72 years), had more comorbidities (5 vs. 3), and were more likely to be admitted from SNF (15.7% vs. 7.3%) or hospitalized in the past 3 months (11.8% vs. 7.1) (all comparisons P < 0.001). After multivariable adjustment, factors significantly associated with development of CDI included increasing age, admission from a skilled nursing facility, and receipt of piperacillin/tazobactam, aztreonam or intravenous vancomycin (Figure 1). Receipt of third-generation cephalosporins or fluoroquinolones was not an independent predictor of CDI. CONCLUSION: In a large US inpatient sample hospitalized for pneumonia and treated with antimicrobials, only 0.53% of the patients developed CDI as defined by an ICD-9 code and positive laboratory test. Reducing the exposure to healthcare facilities and certain high-risk antibiotics may reduce the burden of CDI in patients with CAP. [Image: see text] DISCLOSURES: All authors: No reported disclosures.