Switching from traditional blood thinners to newer variants leads to more bleeding in vulnerable elderly people with atrial fibrillation compared to continuing the current treatment. This is evident from research by the UMC Utrecht into the safety of transferring blood thinners in vulnerable elderly people with atrial fibrillation. The results of the research were presented on August 27 at a major international cardiology conference in Amsterdam and simultaneously published in the journal Circulation.

About 1 in 10 people aged 75 and older in the Netherlands have atrial fibrillation. People with atrial fibrillation have an increased risk of thrombosis and to reduce this risk, doctors prescribe blood thinners. The FRAIL-AF study aimed to find out whether switching from traditional blood thinners to newer blood thinners leads to less bleeding in vulnerable elderly people with atrial fibrillation. From the randomized study, the researchers now conclude that switching blood thinners (from VKA to NOAC) in vulnerable elderly people with atrial fibrillation leads to more bleeding. The risk of bleeding is 69% higher when patients switch to the newer blood thinners compared to when they remain on traditional blood thinners.

Continue traditional blood thinners

The newer blood thinners are more often chosen over traditional blood thinners, because of the lower risk of serious bleeding and therefore no or fewer checks at the thrombosis service. This is also a justified choice for non-frail elderly people, but randomized research in vulnerable elderly people has not previously been done. Geert-Jan Geersing, general practitioner and researcher at the UMC Utrecht: “The results of our research therefore show a different result for vulnerable elderly people than what was known from previous research; an unexpected finding, also for ourselves.”

More research into vulnerable elderly people

Scientific research into medicines for vulnerable elderly people is highly desirable because we cannot automatically assume that medicines work in the same way for vulnerable elderly people as they do for non-frail elderly people. Geersing: “We still do this too often in the guidelines with the comment: 'There is no evidence that they work differently'. This is classic circular reasoning: vulnerable elderly people very often do not participate in research, because they are not allowed to participate due to strict inclusion criteria or because a doctor wants to protect them from the burden of research. Because of this, we have no evidence, and because we have no evidence we act as if that evidence is not necessary. Our research shows that this type of research, no matter how difficult it is, is really necessary, especially with the aging population.”

The FRAIL-AF investigation

Researchers from UMC Utrecht, together with doctors and researchers from various thrombosis services throughout the Netherlands, have set up the FRAIL-AF study. The study started in 2018 and has a follow-up duration of one year per patient. The Groningen Frailty Indicator was used in the research. A total of 1,330 patients were randomized between January 2018 and April 2022. The average age was 83 years and 38.8% were female. The research was funded through ZonMw's Good Use Medicines program.

Blood thinners: VKAs and NOACs

In the Netherlands, 373,700 people have atrial fibrillation and more than half of the people with atrial fibrillation are 75 years or older. In atrial fibrillation, the heart rate is irregular and usually too high. People with atrial fibrillation have an increased risk of thrombosis, a blood clot in a blood vessel. To reduce the risk of thrombosis, doctors prescribe blood thinners. There are two different blood thinners: the traditional vitamin K antagonists (VKAs) and the non-vitamin K antagonist oral anticoagulants (NOACs). Both drugs are very effective when it comes to preventing a stroke.