Background: Atrial fibrillation (AF) is associated with a risk
for cognitive impairment and dementia, which is more pronounced in
patients with a history of clinical stroke. Anticoagulation use and
efficacy impact long-term risk of dementia in AF patients in
observational trials. Methods: The Cognitive Decline and
Dementia in Patients with Non-Valvular Atrial Fibrillation (CAF) Trial
was a randomized, prospective, open-label vanguard clinical study with
blinded endpoint assessment involving patients with moderate- to
high-risk (CHADS2 or CHA2DS2-Vasc scores of ≥2) non-valvular AF assigned
to dabigatran etexilate or warfarin. The primary endpoint was incident
dementia or moderate cognitive decline at 24 months. Results: A
total of 101 patients were enrolled, of which 50 received dabigatran and
51 warfarin anticoagulation. The mean age was 73.7±6.0 years and
54(53.5%) were male. Prior stroke and stroke risk factors were similar
between groups. Average INR over the study was 2.41±0.68 in the warfarin
group. No patient experienced a stroke or developed dementia.
Mini-Mental Status Evaluation, Hachinski Ischemic scale, cognitive
subscale of the Alzheimer’s Disease Assessment Scale, Disability
Assessment for Dementia, Quality of Life Improvement as assessed by
Minnesota Living with Heart Failure Scale and the Anti-Clot Treatment
Scale Quality of Life Survey scores did not vary at baseline or change
over 2 years. Biomarker analysis indicated a similar efficacy of
anticoagulation strategies Conclusion: Use of dabigatran and
well-managed warfarin therapy were associated with similar risks of
stroke, cognitive decline, and dementia at 2 years, suggestive that
either strategy is acceptable to mitigate these risks. The results of
this Vanguard study did not support the pursuit of a larger formally
powered study.