Background: Atrial fibrillation is associated with several comorbidities, particularly cognitive impairment and dementia, especially in older patients. Non-vitamin K oral anticoagulants (NOACs) or vitamin K antagonists (VKAs) were used to prevent thromboembolic events. However, data on the real benefit of these drugs on cognitive function decline remains controversial. In this study we evaluated the effect of NOACs compared to VKAs on the absolute and relative decline in cognitive function over time.

Methods: Nine hundred and eighty-three older patients with nonvalvular AF were enrolled (76 ± 6 years; 291 on VKAs and 692 on NOACs). The cognitive function was assessed with Mini Mental State examination (MMSE) score. The between-arms difference of cognitive evolution over time was investigated by Linear Mixed Models and group-based trajectory model analyses.

Results: In the whole multicenter observational study, after a long follow-up of 7.2 ± 3.4 years, the patients of the NOACs versus VKAs group had lowest absolute reduction of the MMSE score between baseline and follow-up (-0.3 ± 0.03 vs.-1.7 ± 0.1, p < 0.001). After stratification into five subgroups according to trajectories of MMSE score over time, the probability to belong to trajectories with lower decline in cognitive functions was higher in patients on NOACs than in those on VKAs (3.93-13.88 times).

Conclusion: In older patients with atrial fibrillation, the use of NOACs was associated with a smaller decline of cognitive function over time compared to the VKAs, regardless that patients in the NOACs group were older and with a higher burden of comorbidities.