RSV may elevate risk for stroke, heart failure hospitalization
Key takeaways:
- Respiratory syncytial virus was linked to elevated incidence of cardiovascular events in older adults.
- Future research will help decide whether vaccination could reduce the impact of RSV on the heart.
CHICAGO — Acute respiratory syncytial virus was associated with elevated incidence of cardiovascular events among older adults, specifically HF hospitalization and stroke, according to new research.
Mats C. Højbjerg Lassen, MD, of the department of cardiology at Herlev and Gentofte Hospital and Center for Translational Cardiology and Pragmatic Randomized Trials (CTCPR) in Hellerup, Denmark, and colleagues conducted a self-controlled case series study to evaluate the relationship between acute respiratory syncytial virus (RSV) and CV events. The researchers presented their data at the American College of Cardiology Scientific Session.
“We sought in our study to assess the temporal relationship between acute RSV infection and incidence of cardiovascular events using nationwide RSV testing data from the 2022/2023 winter season in Denmark, as prior studies of both influenza and COVID-19 have shown that the incidence of severe cardiovascular events like myocardial infarction and ischemic stroke were increased following acute infection,” Lassen told Healio. “Given that vaccination against RSV is now available, data from observational studies such as ours may help to inform on groups at risk and immunization strategies.”
As Healio previously reported, the first RSV vaccine (Arexvy, GSK) was approved by the FDA in 2023 and is indicated for the prevention of lower respiratory tract disease in adults aged 60 years and older.
Lassen and colleagues’ analysis utilized the nationwide Danish health care registries to assess the incidence of CV events during the acute phase of the RSV infection, including HF hospitalization, ischemic stroke and MI.
During the 2022 to 2023 RSV season, 34,035 Danish citizens were tested for RSV, of whom 2,655 tested positive (mean age, 78 years; 46% men). The prevalence of diabetes, hypertension, HF, atrial fibrillation and chronic obstructive pulmonary disease was similar in the RSV-positive population compared with all who were tested.
The acute phase of RSV infection was defined as the risk interval of 14 days after a positive RSV test result. The control interval was defined as the time from Sept. 16, 2022, to May 31, 2023, excluding the risk interval.
Lassen and colleagues observed higher incidence of CV events during the acute phase of RSV infection compared with the control period, and reported the following incidence rate ratios (IRR):
- HF hospitalization (IRR = 4.4; 95% CI, 2.4-8.1; P < .001);
- stroke (IRR = 8.1; 95% CI, 3.3-20.1; P < .001);
- major adverse CV events (IRR = 5; 95% CI, 3.2-8; P < .001); and
- any CV event (6.3; 95% CI, 4.7-8.6; P < .001).
The link between acute RSV infection and MI was not significant (IRR = 3.2; 95% CI, 0.9-11.2; P = .06), according to the results.
“We found that the incidence of both HF hospitalization and ischemic stroke were four to eight times higher during the 14 days after testing positive for RSV compared with the control period among citizens undergoing RSV testing as part of routine care,” Lassen told Healio. “We also assessed a broader endpoint of any CV event and found that the incidence was elevated by a factor of 6 compared with the control period. These results suggest that RSV infection may confer an increased risk of CV events.”
The association between RSV infection and CV events remained robust when evaluated in sensitivity analyses accounting for varying risk intervals, restricting to survivors, restricting to individuals without a recent prior CV event, accounting for event dependency and using calendar month as an underlying timescale, according to the results.
The data were simultaneously published in the Journal of the American College of Cardiology.
“We hope our results, together with prior studies that have observed elevations in CV event incidence following influenza and COVID-19 that respiratory virus infections may act as a trigger for CV events, will make health care providers aware of the possible severe CV complications of respiratory virus infections among hospitalized patients,” Lassen told Healio. “Hopefully, raised awareness can help in preventive measures and monitoring, which could help handle the associated risk. It may also help on guiding RSV immunization strategies to ensure that those at risk are adequately protected.
“As RSV vaccines were recently approved, we now have an intervention that has demonstrated to protect against RSV-related lower respiratory tract disease,” Lassen said. “Given our results, it would be important to assess the effect of the RSV vaccines on cardiorespiratory hospitalization endpoints to assess whether an RSV vaccine could reduce the incidence of cardiovascular events among at-risk populations. We are currently running a large-scale pragmatic RSV vaccination trial powered for cardiorespiratory hospitalization endpoints, and it will be interesting to see whether there is evidence of a cardioprotective effect of the RSV vaccines.”
In a related editorial published in JACC, Pekka J. Vartiainen, MD, PhD, of the Institute for Molecular Medicine Finland (FIMM), HiLIFE, at University of Helsinki, and colleagues discussed the potential impact of RSV vaccination on preventing mortality in high-risk populations.
“These findings underscore the substantial and often underestimated impact of RSV on older adults, reinforcing the urgency of targeted interventions to reduce morbidity, mortality and health care burden,” Vartianinen and colleagues wrote.
“To reduce severe outcomes, the CDC recommends a single FDA-approved RSV vaccine dose for adults [aged 75 years and older] and those [aged 60 to 74 years] at increased risk, including those with heart failure, coronary artery disease or congenital heart disease (excluding isolated hypertension),” the authors of the editorial wrote. “For every 1 million vaccinations, an estimated 4,000 to 6,000 RSV hospitalizations and 300 to 800 deaths may be prevented. Further research is needed to refine these estimates and assess risks.”
References:
- Lassen MCH, et al. J Am Coll Cardiol. 2025;doi:10.1016/j.jacc.2025.02.031.
- Vartiainen PJ, et al. J Am Coll Cardiol. 2025;doi:10.1016/j.jacc.2025.03.007.
For more information:
Mats C. Højbjerg Lassen, MD, can be reached at mats.christian.hoejbjerg.lassen@regionh.dk or on X at @matslassen and @CTCPR.
Collapse
Lassen MCH, et al. Cardiovascular Disease Prevention 09. Presented at: American College of Cardiology Scientific Session; March 29-31, 2025; Chicago (hybrid meeting).