P54 Predicting outcomes of patients hospitalised with an acute respiratory deterioration of idiopathic pulmonary fibrosis

Introduction Acute respiratory deteriorations of idiopathic pulmonary fibrosis (ARDIPF) have a poor prognosis, and new developments including antifibrotics may affect outcome. Few studies have investigated risk factors associated with poor outcomes. Objectives To define characteristics of hospitalised ARDIPF patients and investigate risk factors for adverse outcome. Methodology A retrospective cohort analysis of hospitalised ARDIPF patients between January 2014 and December 2018. Clinical records, blood results, microbiological and radiological investigations were examined to identify patient characteristics associated with increased mortality. Mann Whitney U and Chi square were applied as appropriate. Results One-hundred and ninety ARDIPF admissions (in 142 patients) were identified; (63% male, median age 77yr (IQR 70–84), 50% definite-UIP and 24% probable-UIP at diagnosis with 26% patients having undefined radiology on admission). Median length of stay was 7 days (IQR 3–14). 19% patients (n=27) were receiving antifibrotic medication on admission (Nintedanib n=15, Pirfenidone n=12). A precipitating cause was definitively identified in 61% (n=115) of admissions (cardiac failure 15% (n=17/115), pulmonary embolus 7% (n=8/115), infection 78% (n=90/115). The remainder of admissions were attributed to idiopathic acute exacerbations (n=35), or other causes including disease progression (n=40) (Figure One). In cases attributed to infection, a pathogen was identified in 25% (n=23). The majority of microbiological diagnoses were made by sputum culture (83%), 17% by viral PCR. All-cause inpatient mortality was 16% (n=30/190) (30-day mortality 21%, 90-day mortality 31%). Those ARDIPF associated with a causative pathogen had a lower inpatient mortality than both those ARDIPF attributed to infection but no organism identified (35%) and in those with idiopathic acute exacerbations (18%) (respective P-values Age, gender, use of antifibrotics, and preceding radiological pattern of fibrosis were not associated with all-cause inpatient mortality (P>0.05). Conclusions ARDIPF mortality remains high, with better outcomes in those patients with an identified respiratory pathogen. Further studies should investigate if improved microbiological diagnosis of ARDIPF improves patient survival.