Health and Medicine
PUBLISHED
One of the most important aims of any vaccine is to prevent serious outcomes of infection. COVID-19 vaccines have proven very effective at limiting the risk of hospitalization and death from the virus throughout the pandemic – from the first tentative steps out of lockdown through the ever-mutating Omicron subvariants.
The rest of this article is behind a paywall. Please sign in or subscribe to access the full content.Most of the symptoms we associate with COVID are linked to the respiratory system, but we know that when people get seriously unwell, it’s not only their lungs that are affected. A new study from scientists at the US Department of Veteran Affairs (VA) demonstrates how vaccines can protect another vital system at risk from COVID: the cardiovascular system.
“Infection with SARS-CoV-2 is associated with an increased risk of major adverse cardiovascular events (MACEs) that can extend well beyond the acute phase,” the new paper reads.
That means there’s a risk of heart complications during the initial infection and afterwards too, as organizations like the World Heart Organization have highlighted: “Cardiovascular consequences include accelerated vascular ageing, plaque instability, and increased long-term risk of myocardial infarction [MI], with millions still living with ongoing cardio-respiratory symptoms as part of long COVID.”
Indeed, large-scale research has previously corroborated the finding that long COVID increases the risk of cardiovascular disease.
But prior research has also suggested that COVID vaccination can help limit the risk of these complications, and this is what this latest study found too.
“This cohort study aimed to respond to the critical public health question: Do COVID-19 vaccines still reduce the risk of MACE in 2024 through 2025?” the researchers wrote.
To find out, they looked at data from a total of over 1 million adults who had contact with the VA health system between September 3 and December 31, 2024.
All participants received a flu vaccine, and some (349,085) also got a COVID shot at the same time. The team wanted to compare those who got both vaccines with those who only got the flu shot.
COVID-19-associated MACEs covered four separate scenarios: death from cardiovascular complications, MI (otherwise known as a heart attack), stroke, and hospitalization for heart failure. The cohort was observed for eight months, or until one of these outcomes occurred.
Receiving a COVID vaccine was associated with a significantly lower risk of COVID-associated MI, heart failure, and death from cardiovascular disease. The difference for stroke, specifically, was not found to be statistically significant.
Looking deeper at the data, the authors found that these significant effects were only seen in individuals older than 75 years. The benefit was greatest in those with other underlying medical conditions.
“In this nationwide cohort study of veterans,” the authors concluded, “the 2024-2025 COVID-19 vaccine was associated with a lower risk of COVID-19–associated MACE; absolute risk reductions were generally modest, but more pronounced in older adults and individuals with comorbidities.”
The authors made efforts to include as diverse a range of participants as possible, but they state that the US veteran population inherently leans white, male, and older, so that may limit the generalizability of the findings.
As to why the vaccine might offer this extra protective benefit in some people, they speculate that it comes down to reducing the severity of COVID infections – this means there’s less inflammation and tissue injury happening, which can have the knock-on effect of causing cardiovascular complications.
The bottom line? COVID vaccines are still beneficial, and even more so for older people and those with conditions that make them more vulnerable to serious infections.
To add to that: gone are the days when many of us kept stocks of COVID tests on hand. Keeping up to date with vaccines, the authors point out, means these cardioprotective benefits are there even when we may not realize we’ve even had COVID.
“These findings suggest that the vaccine’s benefit extends well beyond clinically confirmed COVID-19–associated sequelae by mitigating the substantial burden of events precipitated by undiagnosed SARS-CoV-2 infection that are missed by disease-specific surveillance.”
The study is published in the journal JAMA Internal Medicine.
