Retrospective Comparison of Patients ≥ 80 Years With Atrial Fibrillation Prescribed Either an FDA-Approved Reduced or...

Area of Science:

• Cardiology
• Geriatrics
• Pharmacology

Background:

• Direct-acting oral anticoagulants (DOACs) are standard for stroke prevention in atrial fibrillation (AF).
• Limited data exists on DOAC efficacy and safety in patients aged 80 years and older.
• Elderly patients often have comorbidities influencing treatment decisions.

Purpose of the Study:

• To evaluate the safety and efficacy of reduced-dose versus full-dose DOACs in patients with AF aged 80 years and older.
• To compare rates of stroke and systemic embolization (SSE), bleeding events, and mortality between DOAC dose groups.
• To identify baseline characteristics associated with DOAC dose selection in this elderly population.

Main Methods:

• Retrospective analysis of AF patients aged ≥80 years prescribed reduced or full-dose DOACs (Dabigatran, Rivaroxaban, Apixaban).
• Data collected from January 1, 2011, to May 31, 2017.
• Multivariable analysis to identify differences in baseline characteristics and outcomes.

Main Results:

• Patients on reduced-dose DOACs were older, had poorer renal function, and more comorbidities.
• Rates of SSE and central nervous system (CNS) bleeds were low and similar between groups.
• Non-CNS bleed rates were significantly higher in the reduced-dose group (10.89%/yr vs 4.15%/yr).
• Mortality rates were significantly higher in the reduced-dose group (6.24%/yr vs 1.75%/yr), even after adjustment.

Conclusions:

• DOACs effectively reduce SSE with low CNS bleeding risk in elderly AF patients (≥80 years), irrespective of dose.
• Higher non-CNS bleed and mortality rates in the reduced-dose group are attributed to higher-risk baseline characteristics.
• Further research is needed to understand the causes of non-CNS bleeds and mortality in this population.