THE CLINICAL IMPACT OF HOSPITALIZATION DUE TO RESPIRATORY SYNCYTIAL VIRUS AND HUMAN METAPNEUMOVIRUS AS COMPARED TO INFLUENZA A IN THE ADULT POPULATION

Abstract

Background: Respiratory Syncytial Virus (RSV) and Human Metapneumovirus (hMPV) are major respiratory pathogens in children, and are increasingly recognized as causes of significant illness in the adult population, particularly in seniors. Furthering our understanding of the clinical context of these illnesses will inform policy and practice on how best to use treatment and preventative measures when they become available. Methods: First, we conducted a retrospective chart review of adult patients hospitalized with RSV, hMPV, or Influenza A (2011-2016) at St. Joseph’s Healthcare Hamilton. All RSV and hMPV inpatients were included in the study, and a random sample of inpatients with Influenza A in each year were then selected. Second, we conducted an analysis of The FOREVER cohort (2011-2014), a linked laboratory and administrative data set that included the three major acute care centres in the Hamilton/Niagara Region. Outcomes were length of hospital stay, mortality, and changes in disposition post-hospitalization. Results: Patients with RSV (p<0.001) and hMPV (P=0.04) were observed to be older than those with influenza A and be more likely to reside in long term care facilities. Moreover, patients that were hospitalized with RSV and hMPV had longer lengths of hospital stay and higher odds of mortality after controlling for age, sex, and comorbid conditions in multi-variable models. There were no differences observed in changes of disposition following hospitalization between the three infections groups. There was a high level agreement between the two methodologies with regard to baseline characteristics, length of stay, and mortality. Differences were observed in the proportions of patients that were admitted to the ICU during their hospital stay and the proportion that were discharged to long term care facilities. Conclusions: RSV and hMPV in adult inpatients was half as common as Influenza A, and had comparable, if not worse outcomes.