Clinicians often worry about prescribing blood thinning medications to older patients because of concerns about falls and major bleeding, but research in England suggests that for patients with atrial fibrillation (AF), the health risks of not taking these drugs are significantly higher than the risk of a life-threatening bleed.
AF is associated with a fivefold increase in the risk of stroke. It also increases the risk of heart attacks and death. Anticoagulants are highly effective in managing AF and preventing strokes and other complications.
Older people also tend to fall more frequently, with falls being a leading cause of injury among adults aged 65 and older. These can lead to serious injuries, such as hip fractures and head injuries.
However, the latest study from the University of Bath, published in Heart, found that contrary to popular medical belief, stopping anticoagulants for patients aged 75 and over does not change the risk of major bleeds.
These findings are important for clinicians to factor into their prescribing behaviour, according to the study’s authors.
“Prescribers need to consider the increased risk to patients of coming off anticoagulants, including stroke,” said Dr Anneka Mitchell, who led the study and is a visiting researcher at the University’s Department of Life Sciences.
Rising cases
Cases of AF are rising in all age groups but particularly among people aged 85 and over, where cases have doubled in men from 11.6% to 22.1% between 2000 and 2016, and increased in women from 9.6% to 16.5%. There are no data available to show trends from 2016.
Though there is a large body of evidence supporting the use of blood thinners for older people with AF, this study is believed to be the first to measure patient outcomes when anticoagulant medication is stopped.
Mitchell’s team analysed data from the UK Clinical Practice Research Datalink between 2013 and 2017, focusing on patients of 75 and older who were newly prescribed anticoagulants.
It found the risks of stroke and death were three times higher during periods when patients were not receiving anticoagulation therapy. Heart attack risks was nearly double compared with when they were taking anticoagulants.
Warfarin vs direct oral anticoagulants
Mitchell believes that apart from concern about falls, many clinicians base their decisions to withhold anticoagulants on the historic experience of patients taking warfarin.
The only available option for treating AF until 2012, the drug is associated with a complex medication regimen, along with dietary restrictions and frequent blood-tests, making treatment difficult for many older patients.
Since 2013, however, a new family of drugs called direct oral anticoagulants (DOACs) have become the first line option for most patients, as effective and safe as warfarin – sometimes more so – and far more straightforward to take.
Mitchell said: “For example, apixaban (a DOAC) has a lower risk of significant bleeding than warfarin, so for many older patients with AF, this is an excellent medication.
“Our findings highlight the critical need for clinicians to carefully consider the risks of stopping anticoagulation therapy in older patients. Despite concerns about bleeding, this study suggests that discontinuing blood thinners does not significantly affect the risk of major bleeding but raises the risk of stroke and death.”
Older patients
Dr Anita McGrogan, who led the research team from the Department of Life Sciences at Bath, said: “Older patients were poorly represented in clinical trials that evaluated the efficacy and safety of DOACs before these products were licensed, and those who were included were healthier than many people in the target group for prescribing. So, the safety of these medications for people aged 75-plus was not evaluated, and many chose to avoid prescribing them for older people.
“This study has filled the information gap by looking at anonymous data on 20 167 people who were over 75, demonstrating the value of using big data to investigate important clinical questions, especially in vulnerable populations.”
Study details
Safety and effectiveness of anticoagulation therapy in older people with atrial fibrillation during exposed and unexposed treatment periods
Anneka Mitchell, Margaret Watson, Tomas Welsh, Anita McGrogan.
Published in Heart in February 2025
Abstract
Background
Anticoagulation therapy reduces stroke risk in patients with atrial fibrillation (AF), but it is often underused in older populations due to concerns about bleeding. This study aimed to compare the safety and effectiveness of anticoagulation during periods of exposure and non-exposure and across different anticoagulants in people with AF aged ≥75 years.
Methods
Using UK primary care data from the Clinical Practice Research Datalink (2013–2017), a retrospective cohort study was conducted on patients newly prescribed oral anticoagulants (warfarin or direct oral anticoagulants). Exposure to anticoagulation was mapped using prescription data. Cox regression models were used to estimate adjusted HRs for stroke, bleeding, myocardial infarction, and death during periods of exposure and non-exposure and for different anticoagulants.
Results
Among 20 167 patients (median age 81 years), non-exposure to anticoagulation was associated with higher risks of stroke (HR 3.07, 95% CI 2.39 to 3.93), myocardial infarction (HR 1.85, 95% CI 1.34 to 2.56) and death (HR 2.87, 95% CI 2.63 to 3.12) compared with exposure. Compared with warfarin, apixaban was associated with lower risks of non-major bleeding (HR 0.73, 95% CI 0.64 to 0.85), whereas rivaroxaban was associated with higher risks of major (HR 1.33, 95% CI 1.15 to 1.55) and non-major (HR 1.29, 95% CI 1.16 to 1.44) bleeding.
Conclusions
Non-exposure to anticoagulation increases the risks of stroke, myocardial infarction and death in older patients with AF. Clinicians should carefully weigh the risks of discontinuing anticoagulation and provide shared decision-making support to patients, especially when considering deprescription.
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