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.