Rationale and design of the impact of anticoagulation therapy on the Cognitive Decline and Dementia in Patients with Nonvalvular Atrial Fibrillation (CAF) Trial: A Vanguard study

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. Observational trials suggest that the implementation and quality of long-term anticoagulation impact dementia risk. Emerging evidence suggests that direct oral anticoagulants may improve long-term risk of dementia in AF patients. This manuscript describes the rational and trial design of the the Cognitive Decline and Dementia in Atrial Fibrillation Patients (CAF) Trial. CAF investigates if AF patients randomized to dabigatran etexilate will have long-term higher cognition scores and lower rates of dementia compared in the long term to dose-adjusted warfarin (International Normalized Ratio [INR]: 2.0-3.0). As of 27 February 2019, a total of 120 subjects will be enrolled at one investigational site in the United States and will be followed for 2 years after study enrollment. To date, 97 have been enrolled. The average age is 74.2 years, 53% are male, and 9% had a prior stroke. In this Vanguard study, patients will be followed for 2 years after study enrollment. These prospective, randomized data will inform the understanding of two anticoagulants in AF patients as it relates to risk of cognitive decline and dementia. Cranial imaging and biomarkers collected will assist in understanding mechanisms of brain injury.