Oral Anticoagulants in Older Adults with Atrial Fibrillation

In a study in the Journal of the American Geriatrics Society, researchers sought to characterize any associations between oral anticoagulation (OAC) and bleeding or stroke events in patients aged ≥80 years with atrial fibrillation (AF) and reveal historical trends in OAC prescriptions for this population. According to the primary investigator Stephanie L. Harrison, “the proportion of people aged ≥80 years receiving OAC has increased since the introduction of non-vitamin-K antagonist oral anticoagulant (NOAC) but remains low.”

The retrospective study assessed patients aged ≥80 years with AF who were receiving a NOAC, warfarin, or no OAC between 2011 and 2019. Participants were sorted by treatment and matched for factors including age, sex, ethnicity, and comorbidities.

Reportedly, the proportion of these patients receiving any OAC increased from 32.4% (n = 27,647) in 2011 to 43.6% (n = 110,412) in 2019. A total of 169,067 patients with AF were ultimately included in the no OAC and NOAC groups. Compared with the no OAC group, patients receiving a NOAC had a lower risk of:

• Incident dementia (hazard ratio [HR] = 0.68; 95% CI, 0.65–0.71)
• All-cause mortality (HR = 0.49; 95% CI, 0.48–0.50)
• First-time ischemic stroke (HR = 0.87; 95% CI, 0.83–0.91)

However, NOAC use was associated with a higher risk of major bleeding than no OAC use (HR = 1.08, 95% CI, 1.05-1.11). Furthermore, compared with warfarin, patients on a NOAC had a lower risk of:

• Dementia (HR = 0.90; 95% CI, 0.86–0.93)
• All-cause mortality (HR = 0.74; 95% CI, 0.72–0.76)
• Ischemic stroke (HR = 0.86; 95% CI, 0.82–0.90)
• Major bleeding (HR = 0.88; 95% CI, 0.85–0.90)

The authors added that results were similar in a subgroup of people with additional bleeding risk factors.

Ultimately, the authors concluded that use of a NOAC “was associated with improved outcomes compared to warfarin, and compared to no OAC, except for a small but statistically significant higher risk of major bleeding.”