Dementia risk reduction between DOACs and VKAs in AF: A systematic review and meta-analysis

Direct oral anticoagulants (DOACs) become the recommended treatment over vitamin K antagonists (VKA) in patients with non-valvular atrial fibrillation (AF). However, their effectiveness in reducing cognitive impairment and dementia compared to VKA remains unclear.

A systematic literature search was conducted on Ovid MEDLINE, EMBASE, and Cochrane Database. Randomized controlled trials, cohort, or case-control study that assessed incident dementia between AF patients who received DOAC compared to VKA were selected. Relevant study characteristics and the number of incident dementia diagnosis or hazard ratios (HRs) for incident dementia and each dementia subtypes were extracted. Random-effects model was used to perform meta-analysis. Standardized mean differences (SMDs) were used to estimate effect sizes for continuous data.

Twelve cohort studies comprising 1 451 069 individuals were included. The incidence of dementia was lower in AF patients prescribed DOACs compared to VKA (HR 0.88, 95% CI 0.83-0.93, I ² = 61.2%). A lower incident dementia in DOACs group relative to VKA was significantly observed in those less than 75 years of age (< 65 years, HR 0.83 (95% CI 0.72-0.97, I ² = 0%); 65-74 years, HR 0.86 (95% CI 0.81-0.92, I ² = 55.4%); and ≥ 75 years, HR 1.07 (95% CI 0.74-1.55, I ² = 92.5%)) and for the subgroup of patients with vascular dementia (HR 0.91, 95% CI 0.824-0.997, I ² = 0%).

This meta-analysis reveals a reduction in incidence of dementia in AF patients prescribed DOACs compared to VKA, particularly in those less than 75 years old and in the vascular dementia subtype.