Evaluating RSV Risk in Adults: Impact of Age, Comorbidities, and Race on Hospitalization

Overview

Respiratory syncytial virus (RSV) hospitalization risk in adults is significantly influenced by preexisting medical conditions and racial/ethnic factors rather than age alone. Adults with congestive heart failure, coronary artery disease, COPD, and diabetes show markedly higher hospitalization incidence, with Black and Hispanic adults experiencing disproportionately elevated rates across age groups.

Background

RSV is a major cause of respiratory illness leading to hospitalization and mortality in adults, especially older adults and those with chronic conditions. Recent FDA approvals of RSV vaccines target adults aged 60 and older, but recommendations for younger high-risk adults remain limited. Understanding how age, comorbidities, and race/ethnicity affect RSV hospitalization and severe outcomes is critical for optimizing vaccine guidelines. This study analyzed RSV hospitalizations over three winters (2017–2020) in two US cities to clarify these relationships.

Data Highlights

RSV hospitalization incidence was 2.5-fold higher for Black adults aged 18–44 years and 8-fold higher for those aged 45–64 years compared with other races. Hispanic adults had 2-3-fold higher hospitalization incidence across all age groups compared with non-Hispanics. COPD increased risk of ICU admission or in-hospital mortality by 1.9-fold (97.5% CI, 1.27–2.68).

Key Findings

• Adults with CHF, CAD, COPD, and diabetes have significantly higher RSV hospitalization incidence rates, with CHF showing the highest risk (IRR 13.66).
• Asthma, obesity, and immunosuppression are more prevalent among younger adults (≤65 years) hospitalized with RSV.
• Black adults aged 18–44 years have a 2.5-fold, and those aged 45–64 years an 8-fold higher RSV hospitalization incidence compared to other races.
• Hispanic adults experience 2-3 times higher RSV hospitalization incidence across all adult age groups compared to non-Hispanics.
• COPD is associated with a 1.9-fold increased risk of ICU admission or in-hospital mortality and, along with CHF, increases 6-month all-cause mortality risk.
• Age ≥65 years alone was not independently associated with increased risk of ICU admission, in-hospital mortality, or 6-month mortality after hospitalization for RSV.

Clinical Implications

RSV vaccination strategies should prioritize adults with specific high-risk medical conditions such as CHF, COPD, CAD, and diabetes, regardless of age. Additionally, racial and ethnic disparities in RSV hospitalization incidence highlight the need for targeted outreach and vaccination efforts in Black and Hispanic populations. Current vaccine recommendations may need revision to include younger adults with these risk factors to reduce severe RSV outcomes.

Conclusion

Preexisting medical conditions and racial/ethnic factors are critical determinants of RSV hospitalization risk and severity in adults, more so than age alone. Incorporating these factors into vaccine guidelines could improve prevention of severe RSV disease across diverse adult populations.

References

1. Falsey et al. 2024 -- Evaluating the Risk of Respiratory Syncytial Virus in Adults