Dementia Risk in Atrial Fibrillation Increases With Delayed Anticoagulation

Doctor Comforting Patient Dementia
Doctor Comforting Patient Dementia
The delayed start of anticoagulation treatment for atrial fibrillation has been linked to an increase risk for dementia.

Delays in starting anticoagulation treatments in atrial fibrillation (AF) increases the risk for dementia, according to research presented at the Heart Rhythm Society’s 38th Annual Scientific Sessions, May 10-13, in Chicago, Illinois.1

T. Jared Bunch, MD, director of Heart Rhythm Research at Intermountain Medical Center Heart Institute and medical director for Heart Rhythm Services for the Intermountain Healthcare system, in Salt Lake City, Utah, and colleagues conducted the study to determine whether anticoagulation delays in AF treatment increased long-term risk of dementia.

The study included 76,230 patients with AF without a history of dementia. The average age was 69.2±12.7 years and 56.8% of patients were men. Hypertension, diabetes, and heart failure were among the risk factors present in patients. The primary end point was incident dementia.

Patients were separated by therapy: antiplatelet (n=10,461) or warfarin anticoagulation (n=64,647). Delays between AF diagnosis to antiplatelet or anticoagulant treatment was separated by ≤30 days in 43.6% of patients, 31 days to 1 year in 10.6% of patients, >1 year to 3 years in 13.5% of patients, or >3 years in 32.3% of patients.

When antiplatelet (aspirin) or anticoagulation (warfarin) therapy did not begin within 30 days of AF diagnosis, the multivariate adjusted risk for dementia increased (hazard ratio [HR] 1.63; P =.05). There was also a relative risk directly associated with baseline risk (CHADS2 VASc 0-1: HR 1.30; P =.75; CHADS VASc 2-4: HR 1.50; P =.19, CHADS2 VASc >5: HR 2.36, P =.07).

“In this study, the benefit was derived from using warfarin and we hope that newer anticoagulants that perform better than warfarin and are easier to start and use will further improve dementia risk,” said Dr Bunch said in a press release from the Heart Rhythm Society.2

The researchers have launched a prospective study examining dabigatran vs warfarin to closely study cognitive changes over a 2-year period.

Related Articles


  1. Bunch TJ, May HT, Bair TL, et al. Dementia rates increase with delays in initiation of anticoagulation treatment for atrial fibrillation. Presented at: Heart Rhythm Society’s 38th Annual Scientific Sessions. May 10-13, 2017; Chicago, Illinois.
  2. New study shows delayed use of blood thinners for atrial fibrillation increases risk of dementia [press release]. Chicago, IL: Heart Rhythm Society; May 12, 2017.