RSV Infection Ups CV Risk for Older Adults, Albeit With Some Heterogeneity

Among adults older adults, a respiratory syncytial virus (RSV) infection increases the risk of cardiovascular events over the following year, according to new Danish data. Researchers say its effect on CV risk matches that of influenza.

A lab-confirmed case of RSV led to an additional 4.69 events per 100 people—including ischemic heart disease, stroke, heart failure, arrhythmias, venous thromboembolism, and inflammatory heart disease—compared with those without infection. Most of these events occurred within 30 days, and patients who were hospitalized, elderly, and had preexisting CVD and diabetes were at the highest risk.

“The findings of a significant and year-long cardiovascular burden associated with RSV infection, comparable to that of influenza infection, underscores the potential for an important public health impact through RSV vaccination programs in vulnerable populations, such as older adults, which may not only reduce respiratory illness but also play a crucial role in mitigating a considerable burden of subsequent CVD,” Anders Hviid, DrMedSci (Statens Serum Institut, Copenhagen, Denmark), and colleagues write in their JAMA Network Open paper published online today.

“Future research should evaluate the impact of RSV vaccination on cardiovascular outcomes and further explore the mechanisms underlying this prolonged risk,” they suggest.

To TCTMD, Hviid said he was “a bit” surprised that the risk was so high. “This suggests that its having a severe infection where you are bedridden that increases the risk of cardiovascular disease, and less so the specific virus,” he said in an email. “RSV vaccination may prevent cardiovascular disease, and if you are elderly or have preexisting conditions that make you vulnerable to infections, you should consider getting an RSV shot.”

Prior studies have long documented the cardiovascular benefits of influenza vaccination, with email reminder initiatives showing success especially in those with a history of acute MI.

Greater Risk With Age, Comorbidities

The study included 17,494 adults aged 45 years and older (mean age 71.8 years; 57.6% female) from Danish health registries. Half (n = 8,747) who had a lab-confirmed RSV infection between 2019 and 2024 were matched by age, sex, and preexisting comorbid conditions to people without RSV over the same time period. More than two-thirds (69.1%) of the patients with RSV were hospitalized compared with 16.2% of matched controls.

Within 1 year, there were 665 and 257 cardiovascular events in the infection and no infection groups, respectively. The greatest differences in risk were noted in hospitalized patients (6.61 percentage points) and those with preexisting CVD (11.95 percentage points) or diabetes (7.5 percentage points).

Risk rose progressively with higher age, as well. An RSV infection didn’t have a significant impact for patients aged 45-54, but risk increased by 1.44 percentage points among those aged 55-64 with versus without RSV. For ages 65-74, 75-84, 85-94, and 95-104 years, the increases were 3.72, 7.55, 7.93, and 8.13 percentage points, respectively. By 30 days, about half of the CV risk burden had already materialized among patients with RSV compared with those with no infections (3.82 percentage points). When looking at individual endpoints, arrhythmias and heart failure were the most common at both 30 days and 1 year.

“There was a lot of heterogeneity in the burden,” Hviid specified. “If you are 45 years of age, otherwise healthy and have a mild RSV infection, I would not worry. If you are hospitalized, elderly and have preexisting conditions, then the risk of cardiovascular disease is quite significant.”

When matching 8,823 individuals with laboratory-confirmed RSV infection to others with laboratory-confirmed influenza infection, the researchers found no significant differences.

Several studies have examined the effects of both influenza and COVID-19 on CV events, but more work needs to be done looking at this phenomenon in RSV, Hviid said. “We need more insight into the mechanism. Is it all down to having a severe respiratory infection, and less about the specific pathogen?”

The researchers add that they would like to also see additional studies on how much getting vaccinated against RSV can curb cardiovascular risk.