A territory-wide study on adults hospitalized for rhinovirus infection – mortality, severe adverse respiratory and renal outcomes and relationships with multiple comorbidities

Introduction. While rhinovirus was thought to cause mild infections such as the common cold, severe infections such as community-acquired pneumonia and asthma exacerbations can also occur. Children with chronic medical conditions have been shown to have increased risks of severe infections. Hypothesis/Gap statement. There is a difference in the risks of serious in-hospital outcomes among adults hospitalized for rhinovirus or influenza virus infection. Multiple morbidities in adult patients are associated with severe infections among patients hospitalized for rhinovirus infections. Aim. To compare the risks of serious in-hospital outcomes among adults hospitalized for rhinovirus or influenza virus infection and assess the association between multiple morbidities as represented by Charlson comorbidity index (CCI) in predicting risks of severe infections among patients hospitalized for rhinovirus infections. Methodology. We conducted a territory-wide retrospective study on adults hospitalized for rhinovirus or influenza virus infection between 1 January 2016 and 30 June 2023 in Hong Kong. The in-patient mortality, severe respiratory failure (SRF), secondary bacterial pneumonia and acute kidney injury (AKI) were compared. The association between multi-morbidities as reflected by CCI and severe in-hospital outcomes among adult patients hospitalized for rhinovirus infections was also assessed. Results. A total of 41,206 and 2,222 patients were hospitalized for influenza and rhinovirus infections, respectively. Patients with rhinovirus infection showed a significantly higher risk of SRF, secondary bacterial pneumonia and AKI compared to those with seasonal influenza ( P <0.001 for all). Higher CCI (as both continuous variables, by grading as well as cut-off identified by receiver operating characteristic curve analysis) was associated with increased risks of severe in-hospital outcomes. Conclusion. Adults hospitalized for rhinovirus infection were associated with a significantly increased risk of adverse respiratory and kidney outcomes compared with those with seasonal influenza. More medical comorbidities, as reflected by CCI, were shown to be associated with an increased risk of severe in-hospital outcomes.