Linking influenza to risk of later heart problems significantly increased flu vaccination rates among older Danish adults, study presented at American College of Cardiology’s annual scientific session with Congress finds Cardiology World. A reminder message the day before the start of a national vaccination program also helped to “encourage” people to get vaccinated.
Every year, seasonal flu is responsible for more than 500,000 deaths worldwide, and certain high-risk groups are disproportionately affected, including the elderly and people with diabetes, heart disease and other chronic conditions. An annual influenza vaccine is widely recommended to prevent influenza infection or lessen its severity and complications if someone becomes ill. Still, vaccination rates aren’t nearly where they should be in many countries, including the United States, and that’s especially true for young people with chronic conditions like heart disease.
Finding ways to increase the percentage of people who catch the flu [shot] and other vaccines is important. Vaccines help prevent infectious diseases and influenza in particular, many countries are well behind the WHO recommendation that more than 75% of the population should be vaccinated. »
Tor Biering-Sørensen, MD, MSc, MPH, PhD, Professor, Center for Translational Cardiology and Pragmatic Randomized Trials, Copenhagen University Hospital, Hellerup, Denmark, and Chief Study Investigator
While previous studies have tested different nudge strategies — that is, messages designed specifically to educate, remind, and promote positive health behaviors — to increase flu vaccination in certain populations, this study is the largest of its kind and involved all adults aged 65 or over in Denmark.
The NUDGE-FLU trial randomized 964,870 Danish citizens in 691,820 households to receive one of nine different email letters containing a specific message regarding the upcoming flu season and the need for a vaccination to see which one, if any. , would increase the rate of vaccination once morest influenza in the elderly. Communications were delivered through the country’s email system on September 16, 2022. Citizens were either in usual care (no letter) or received one of nine nudge strategies (participants were randomized 1:1, so for every citizen receiving no letters, one received one of the nine intervention letters). In addition to the letter that linked the flu vaccine to a reduction in cardiovascular events, and the approach that sent out the standard flu brochure two weeks before the start of flu season and a reminder on the day the vaccine became widely available, the other seven messages included:
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A clear recommendation from a leading health authority to get vaccinated
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A boost so that people are not in the minority and get vaccinated
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A boost to join the majority to prevent the flu from spreading (collective objective)
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The role influenza vaccination can play in helping to protect you and your loved ones in the event of a pandemic (frame the gain)
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The danger that too few people are vaccinated puts you and your loved ones at risk (framing the loss)
The primary endpoint was receipt of an influenza vaccination on or before January 1, 2023; although flu vaccination can continue throughout flu season, fall is the perfect time to provide protection.
Compared to usual care, flu vaccination rates were significantly higher in the group receiving a letter emphasizing the potential cardiovascular benefits of vaccination (81% vs. 80.12%) and in the group receiving repeated letters regarding the importance of flu vaccination in general and for informing them of available flu vaccines at the start of the study and 14 days later (80.85% vs. 80.12%).
“The only two nudge strategies that significantly increased flu vaccine uptake were simple reminders and explanation that flu vaccination can also prevent cardiovascular events,” Biering-Sørensen said.
He added that these strategies improved vaccination rates in key subgroups, including participants with cardiovascular disease. The cardiovascular benefits message, which stated that “in addition to protecting once morest influenza infection, influenza vaccination also appears to protect once morest cardiovascular disease, such as heart attack and heart failure,” led to more large increase in vaccination among participants who had not been vaccinated once morest influenza during the previous season.
Biering-Sørensen said he expects these increases in flu vaccination to have been even more pronounced in countries with low vaccination rates. Denmark has one of the highest flu vaccination rates to begin with – over 80% this season. During the 2021-2022 flu season, only 49% of American adults received a flu shot, despite widespread recommendations for annual flu shots.
Further research is needed to test messages regarding influenza and associated cardiovascular outcomes, as this was the most effective message to stimulate influenza vaccination.
“As cardiologists, it’s very interesting that just telling people that we can also prevent other downstream issues, such as cardiovascular outcomes, has worked the best of all kickstarter strategies. thumb, even better than the recall, which we expected to be positive,” Biering-Sørensen said. “Many studies have shown that people who get the flu shot have a lower risk of cardiovascular outcomes, and there may be protective effects [for the heart] that are not specific to influenza infection. The flu shot may have broader benefits that we don’t yet know regarding. »
He said these improvements were achieved with a simple email, making it a reproducible, very low-cost intervention that might help prevent flu-related deaths and associated complications. They will further analyze the data to see if certain reminder messages worked better in people with diabetes and other chronic conditions.
The study is limited to the Danish population, which has free access to influenza vaccination, so the increase in vaccination coverage may be different if cost is a barrier.
The study was funded by Sanofi.
This study was simultaneously published online in The Lancet at the time of submission; a predefined analysis of the trial was simultaneously published online in the journal Circulation.
