DOACs Reduce Risk for Dementia in Asian Patients with Atrial Fibrillation

Asian patients treated with direct oral anticoagulants (DOACs), compared with patients receiving warfarin, have reduced risk for dementia, according to a findings published in the Journal of the American College of Cardiology: Asia.¹

Researchers sought to compare the effect of DOACs and warfarin on the risk for dementia in patients with atrial fibrillation (AF). They analyzed 342,624 patients from 10 different studies to compare the incidence of dementia between patients treated with DOACs compared with warfarin for AF. The incidence of dementia was determined by reviewing the incidence of new disease codes for a dementia diagnosis after initiating an anticoagulant at hospital admission. Prospective or retrospective studies that compared the outcome of dementia incidence between patients treated with a DOAC for AF and patients treated with warfarin were included in the meta-analysis. The researchers excluded case reports, case series, reviews, and conference abstracts. The hazard ratio (HR) was pooled to analyze the risk for dementia across all the studies, including propensity score-matched studies. Heterogeneity was measured and subgroup analyses were performed to stratify outcomes for patients aged 75 years and older and patients aged 65 and 75 years.¹

Compared with warfarin, patients treated with DOACs had a significantly lower risk of developing dementia (in 9 of the 10 studies; HR, 0.88; 95% CI, 0.80-0.98; P =.017), but the finding had high heterogeneity (I² =75%). After the patients were stratified by region, Asian patients treated with DOACs were found to have a significantly lower risk of developing dementia compared with Asian patients treated with warfarin (in 4 of the 10 studies; HR, 0.81; 95% CI, 0.68-0.86). The benefits of DOACs in relation to dementia was insignificant in European patients (in 4 of the 10 studies; HR, 0.96; 95% CI, 0.81-1.14).¹  

For the subgroup analyses, researchers found a lower risk of dementia in patients aged 65 to 75 years who were treated with DOACs, compared to those treated with warfarin (HR, 0.80; 95% CI, 0.70-0.91; P <.001; I²=0%). Patients 75 years and older did not significantly benefit from DOACs in relation to dementia risk (HR, 0.94; 95% CI, 0.87-1.02; P =.140; I² =23%). The researchers also found that a lower mean age corresponded to a lower HR favoring DOACs over warfarin (β =.023; 95% CI, 0.002-0.043; P =.03), however this finding had high heterogeneity (I²=70%).¹   

Notably, 6 of the 10 studies were propensity score-matched while the remaining 4 were unmatched. In the subgroups of propensity score-matched studies, patients treated with DOACs had a significantly lower risk of developing dementia than those treated with warfarin (HR, 0.81; 95% CI, 0.73-0.89; P <.001; I² =44%).¹

Study limitations include that most of the studies are not randomized and the incidence of dementia was only recorded using the disease code assigned at hospital admission.¹

Vern Hsen Tan, MBBS and senior consultant in the department of cardiology at Changi General Hospital concludes that, “We would highly recommend DOACs for Asian patients, in particular, as they saw the most benefit of dementia reduction. Nevertheless, the data suggestion of a reversal of this benefit with increasing age warrants further study.”²

Disclosure: One study author declared affiliations with biotech, pharmaceutical, and/or device companies. Please see the original reference for a full list of authors’ disclosures.