Apixaban safer than other options for long-term anticoagulation among the elderly with AF

It is already known that developing an optimal stroke prevention strategy, including OAC or oral anticoagulant therapy, is essential for AF patients living with dementia; it is a condition associated with an increased risk of adverse outcomes. There needs to be more data in this context.

To investigate this background further, a team of researchers did a comparative effectiveness study of 1 160 462 patients with AF with and without dementia.

The researchers drew the following conclusion from the study:

• Apixaban has net clinical benefits compared with other OACs and more significant absolute risk reduction with vs without dementia patients aged 65 years or older with AF.
• Three comparative new-user cohorts were warfarin vs apixaban, dabigatran vs apixaban and rivaroxaban vs apixaban.
• Among dementia patients, compared with apixaban users, a higher rate of the composite endpoint was observed in warfarin users (95.7 events vs 64.2 events per 1000 PYs), dabigatran users (84.5 events vs 54.9 events per 1000 PYs) and rivaroxaban users (87.4 events vs 68.5 events per 1000 PYs) with an adjusted hazard ratio of 1.5, 1.5 and 1.3 respectively.
• The magnitude of the benefits associated with apixaban was similar regardless of dementia diagnosis on the HR scale but differed substantially on the rate difference (RD) scale.
• The adjusted RD of the composite outcome per 1000 PYs for warfarin vs apixaban users was 29.8 events in dementia patients vs 16.0 events without dementia.
• The corresponding adjusted RD estimates of the composite outcome per 1000 PYs were 29.6 events in dementia patients vs 5.8 events in patients without dementia for dabigatran vs apixaban users and 20.5 events in dementia patients vs 15.9 events in patients without dementia for rivaroxaban vs apixaban users.
• There was a more distinct pattern for significant bleeding than for ischemic stroke.

They said, “Apixaban was associated with lower rates of bleeding and ischemic stroke.”

The researchers reported that increased absolute risks associated with other OACs compared with apixaban was higher in dementia patients than those without dementia, particularly for significant bleeding.

The findings of our study support apixaban for anticoagulation therapy in dementia patients who have AF.

The study’s strength includes large nationally representative databases of older adults in the US.

The limitations of the study are misclassified subgroups and unmeasured confounding.

Further reading:

Lin KJ, Singer DE, Bykov K, et al. Comparative Effectiveness and Safety of Oral Anticoagulants by Dementia Status in Older Patients With Atrial Fibrillation. JAMA Netw Open. 2023;6(3):e234086.doi:10.1001/jamanetworkopen.2023.4086