INTRODUCTION
Respiratory syncytial virus (RSV) causes significant morbidity in older adults. It has been estimated that RSV infects 3% to 10% of adults each year1 and contributes to more than 14,000 adult deaths annually in the United States.2 Persons with chronic heart or lung disease and those with immunocompromising conditions appear to be at an increased risk of severe illness from RSV infection.3,4 National mortality and viral surveillance data for respiratory and circulatory deaths estimated that 78% of RSV-associated deaths occurred in persons older than 65 years of age,5 suggesting age is also a risk factor for mortality.7 However, the associations between risk factors such as older age, obesity, and heart, lung, and neurological comorbid conditions and severe outcomes during hospitalization are better understood for influenza than for RSV infection.4
As the RSV season typically coincides with seasonal influenza, generally from October to May,6 and both viruses can cause lower respiratory tract infections and pneumonia, it can be difficult to ascertain the relative contribution of RSV without comprehensive screening and testing for both viruses.7 We performed this nested retrospective study using data derived from a prospective surveillance study for RSV-related hospitalizations in which patients with symptoms of respiratory illness were routinely tested for respiratory viruses. In the current study, we identified hospitalized adults with severe outcomes associated with RSV defined as intensive care unit (ICU) admission, mechanical ventilation, and/or in-hospital death. We compared the demographic characteristics, clinical factors, and living situations on admission of patients with and without severe RSV infection. We hypothesized that even among patients with the same comorbidities, baseline living situation could serve as an indicator of a patient’s underlying health status. Finally, to assess changes in living situations, we explored the impact of RSV-associated hospitalizations on the type of care and the level of care of surviving patients from hospital admission to discharge.