Anticoagulants May Reduce Dementia Risk in AF Patients

Chengxuan Qiu, PhD

Anticoagulants may reduce the risk of a dementia in older people with atrial fibrillation (AF), a new study says. AF is associated with an increased risk of dementia in older people.

The study, published online October 10 in Neurology, was undertaken because growing evidence suggests AF may have an important role in cognitive dysfunction. “Yet, current evidence for the association of AF with cognitive decline and dementia appears to be consistent only among patients with stroke and younger-old adults, but not in very old people (aged 75 years and older),” the authors write.

Plus, given the preventive effect of anticoagulation on AF-related stroke, “it is plausible that use of anticoagulants in patients with AF may also benefit cognitive function and delay dementia onset,” they write.

However, the researchers, with the Karolinska Institute in Stockholm, Sweden, also say that evidence is lacking on the cognitive benefit of antithrombotic drugs from longitudinal population-based studies.

As a result, they reviewed 2,685 dementia-free participants from the Swedish National Study on Aging and Care, people who were regularly examined from 2001 through 2004 and from 2010 through 2013. 

They found that AF was significantly associated with a faster annual Mini-Mental State Examination decline of all-cause dementia and vascular and mixed dementia, but not Alzheimer’s disease.

Among people with either prevalent or incident AF, use of anticoagulant drugs-warfarin (Coumadin), but not antiplatelet treatment, was associated with a 60% decreased risk of dementia.

“While we found evidence that use of anticoagulant drugs could reduce the risk of dementia in patients with AF, our results do not suggest any beneficial effect of antiplatelet therapy in reducing the risk of dementia,” Chengxuan Qiu, PhD, one of the study’s authors and associate professor and senior lecturer in the Aging Research Center at Karolinska Institute, tells Drug Topics.

In addition, novel oral anticoagulants (NOACs) are relatively new medications and were not widely used during the study period. “As NOACs are considered to have lower risk of hemorrhage and do not require serial monitoring, future studies are needed to assess the cognitive benefit of NOACs,” Qui says.

Given that a considerable proportion of older people with AF do not use anticoagulant drugs, it is important that healthcare professionals monitor for AF and improve the clinical management of patients with it, Qui says.

Because the Karolinska Institute study was observational and included an elderly population of a Nordic country with relatively high socioeconomic position, the research findings should be replicated in other populations, according to Qui.