In-hospital and midterm out-hospital complications of adults hospitalised with respiratory syncytial virus infection in France, 2017–2019: an observational study

Abstract

ObjectivesTo describe the clinical characteristics and in/out-hospital outcomes of respiratory syncytial virus (RSV) infection among adults hospitalised with influenza-like illness (ILI) and compared against patients admitted for influenza.MethodsAdults hospitalised with ILI were prospectively included from five French university hospitals over two consecutive winter seasons (2017/2018 and 2018/2019). RSV and influenza virus were detected by multiplex RT-PCR on nasopharyngeal swabs. RSV-positive patients were compared to RSV-negative and influenza-positive hospitalised patients. Poisson regression models were used to estimate the adjusted prevalence ratio (aPR) associated with in-hospital and post-discharge outcomes between RSV and influenza infections. The in-hospital outcome was a composite of the occurrence of at least one complication, length of stay ≥7 days, intensive care unit (ICU) admission, use of mechanical ventilation and in-hospital death. Post-discharge outcome included 30/90-day all-cause mortality and 90-day readmission rates.ResultsOverall, 1,428 hospitalised adults with ILI were included. RSV was detected in 8% (114/1428) and influenza virus in 31% (437/1428). Patients hospitalised with RSV were older than those with influenza (mean age, 73.0 versus 68.8 years; p=0.015) with a higher frequency of respiratory (52% versus 39%, p=0.012) or cardiac chronic diseases (52% versus 41%, p=0.039) and longer hospitalisation duration (median stay 8 versus 6 days, p<0.001). Anti-influenza therapies were less prescribed among RSV than influenza patients (20% versus 66%, p<0.001). In-hospital composite outcome was poorer in RSV patients (adjusted prevalence ratio (aPR)=1.5; 95% Confidence Interval (95% CI) 1.1–2.1) than in those hospitalised with influenza. No difference was observed for the post-discharge composite outcome (aPR=1.1; 95% CI 0.8–1.6).ConclusionRSV infection results in serious respiratory illness with in-hospital outcomes worse than influenza and with similar midterm post-discharge outcomes.