High bacterial coinfection rates and associated mortality among hospitalized older adults with laboratory-confirmed respiratory syncytial virus infection

Abstract

Background: Emerging evidence highlights that respiratory syncytial virus (RSV) poses a significant risk to older adults. However, detailed clinical data on elderly patients hospitalized with RSV remains limited. This study investigates the clinical characteristics and outcomes of older adults (aged ≥50 years) hospitalized with RSV infection. Methods: This retrospective cohort study included hospitalized patients aged ≥50 years with respiratory symptoms and laboratory-confirmed RSV infection at China Medical University Hospital between January 1, 2011, and December 31, 2023. Data on demographic characteristics and clinical presentations were collected. RSV infection-related outcomes were analyzed across various subgroups. Results: This study included 36 patients, with the most prevalent comorbidities being diabetes mellitus (47.2 %), immunocompromised status (36.1 %), and chronic lung disease (30.6 %). Pneumonia was identified in 72.2 % of patients, while 41.7 % required invasive mechanical ventilation, and the hospital mortality rate was 33.3 %. Non-survivors had higher rates of comorbidities, particularly chronic lung disease (66.7 % vs. 12.5 %, p = 0.002), higher disease severity, elevated procalcitonin levels, and were more likely to develop septic shock and acute respiratory distress syndrome. A bacterial coinfection rate of 33.3 % was observed, with patients experiencing pneumonia or bacterial coinfection showing poorer outcomes. Moreover, patients with chronic lung disease exhibited significantly worse day-28 survival (log-rank p < 0.001). Conclusions: The disease burden of RSV in older adults is amplified by comorbidities such as chronic lung disease, with pneumonia and bacterial coinfections further worsening outcomes. Our findings highlight the need for a more comprehensive understanding and effective preventive strategies to protect this vulnerable population.