A large population-based, cross-sectional study from Singapore has revealed that adults hospitalized with respiratory syncytial virus face significantly higher adjusted odds of acute cardiovascular events compared with those hospitalized for COVID-19, regardless of vaccination status. The researchers analyzed 32,960 hospitalizations and found that 1 in 10 patients with respiratory syncytial virus experienced concurrent cardiac complications.
Key Findings
The study researchers examined hospitalizations from January 2017 through June 2024, comparing cardiovascular outcomes among 2,148 patients with respiratory syncytial virus (RSV), 14,389 patients with influenza, and 16,423 patients with COVID-19 during Omicron XBB/JN.1 transmission. Among RSV hospitalizations, 234 patients (10.9%) experienced acute cardiovascular events. Of those, 220 events (94.1%) involved cardiac complications, including dysrhythmias, heart failure, and ischemic heart disease.
Patients with RSV demonstrated significantly higher odds of cardiovascular events compared with both boosted (adjusted odds ratio [AOR] = 1.31, 95% confidence interval [CI] = 1.12–1.54) and unboosted (AOR = 1.58, 95% CI = 1.24–2.01) patients with COVID-19. Dysrhythmia (AOR = 1.52, 95% CI = 1.19–1.94 vs boosted COVID-19) and heart failure (AOR = 1.75, 95% CI = 1.30–2.35 vs boosted COVID-19) were particularly elevated in RSV cases.
Clinical Manifestations and Severity
Dysrhythmia was the most common cardiac complication in RSV hospitalizations: Atrial fibrillation or flutter was identified in 60 of 99 cases (60.6%). In total, 220 of the 234 patients with RSV and cardiovascular events experienced cardiac manifestations, which included:
- 99 dysrhythmias
- 66 episodes of heart failure
- 61 cases of ischemic heart disease
Cardiovascular events significantly increased disease severity across all respiratory viral infections. Patients with RSV who experienced such events had more than double the odds of requiring ICU admission (AOR = 2.36, 95% CI = 1.21–4.62).
Comparison With Other Respiratory Viruses
The relationship between RSV and influenza hospitalizations was more nuanced. While there were no significant differences in overall cardiovascular event rates between patients with RSV and influenza when stratified by vaccination status, a key distinction emerged in postpandemic data: Among 2023 to 2024 hospitalizations, patients with RSV had significantly higher odds of heart failure compared with vaccine-breakthrough influenza cases (AOR = 2.09, 95% CI = 1.21–3.59).
Notably, RSV hospitalizations showed lower odds of cerebrovascular events compared with vaccine-boosted COVID-19 hospitalizations (AOR = 0.28, 95% CI = 0.14–0.56), which pointed to pathogen-specific differences in extrapulmonary effects.
Risk Factors and Demographics
The study population was a mean age of 66.6 years and 51.7% were female. Preexisting cardiac disease emerged as a major risk factor for acute cardiovascular events during RSV hospitalization (AOR = 2.53, 95% CI = 1.84–3.48). Among the total cohort:
- 63.7% had at least one comorbidity
- 19.5% had preexisting cardiovascular disease
- 35.2% had diabetes
The researchers also referenced a modeling study, which showed that RSV’s economic burden in the U.S. is greatest among adults with cardiovascular conditions.
Study Design and Limitations
The researchers used Singapore’s national health databases—Mediclaims and the National Immunization Registry—to identify hospitalizations and vaccination status. RSV and influenza data spanned from 2017 to mid-2024; COVID-19 cases were limited to the Omicron XBB/JN.1 period (2023–2024) to ensure relevant endemic-era comparisons.
Limitations included reliance on administrative claims, which may have resulted in underreporting of mild cardiovascular events, and possible inclusion of incidental COVID-19 cases due to mandatory testing policies, though sensitivity analyses restricted to PCR-confirmed cases confirmed findings.
Clinical Implications
“Given recent availability of RSV vaccination," the authors recommended, "older adults with preexisting cardiac history should be prioritized for vaccination against vaccine-preventable [respiratory viral infections]. Patients with a prior cardiac history might also benefit from more intensive clinical evaluation and monitoring for cardiac events during RSV hospitalization in light of greater risk.”
Author disclosures are available in the published study.
Source: JAMA Network Open
Expert Commentary: Implications for Cardiac Care
Conexiant News interviewed Dr. Ankeet S. Bhatt, MD, MBA, ScM, Associate Physician at Kaiser Permanente San Francisco Medical Center and Division of Research, to discuss the clinical implications of these findings for cardiovascular care.
What should change in how cardiologists monitor patients with RSV?
"There is a well-established link between viral infections and cardiovascular disease across a multitude of viral illnesses—like influenza, COVID-19, and now RSV," Dr. Bhatt explained. "We also know that vaccination can mitigate not just the risk of getting the disease and developing serious complications, but can also reduce cardiovascular events, particularly where the data is most robust, which is in influenza."
He emphasized that, despite physicians' best efforts, large implementation gaps remain in vaccination for influenza and COVID-19, with likely even larger gaps for RSV.
"The main message for cardiologists is this: we need to pay attention. Cardiologists typically don't focus on viral illness, but reducing the incidence and severity of these infections may actually have important implications for heart health."
Priority for high-risk patients
Among patients with preexisting cardiac disease—who showed 2.5 times higher odds of cardiac events during RSV hospitalization—Dr. Bhatt stressed the importance of a comprehensive approach to cardioprotection.
"Patients with cardiovascular disease are clearly at higher risk. Protecting their heart health isn't just about traditional cardioprotective medications and lifestyle changes. It's also about doing everything we can to avoid viral illnesses, including respiratory viruses like RSV."
He noted that, in select patients where vaccination is indicated and approved, RSV vaccination should absolutely be prioritized. "It's not just about improving respiratory health, which is typically how RSV is framed, but potentially about improving heart health as well."
Dr. Bhatt also mentioned ongoing trials examining the impact of RSV vaccination on cardiopulmonary outcomes, noting that while more research is needed, RSV prevention should be considered part of a broader suite of cardioprotective strategies.
"Reducing the incidence and severity of viral infections like RSV may have important implications for heart health. Cardiologists need to pay attention."
— Dr. Ankeet S. Bhatt