Abstract
Background
Direct oral anticoagulants (DOACs) are often used in patients with atrial fibrillation
or flutter instead of warfarin and although supporting evidence is limited, available
studies suggest this may be an acceptable route of care. Our study assessed the question:
are DOACs as effective and safe as warfarin in patients with atrial fibrillation and
class III obesity specifically in a rural population?
Methods
A retrospective analysis was conducted by examining the first 6-12 months of therapy
with a DOAC (apixaban or rivaroxaban) or warfarin in patients with weight >120kg or
class III obesity. Events of interest, thrombosis and bleeding, were documented for
analysis. The risk and odds of events of interest for both groups were calculated
and compared.
Results
Characteristics of both arms were similar (DOAC n=42; warfarin n=43). A lack of thrombosis
events limited efficacy analysis. A total of 22 bleeds occurred with 8 in patients
prescribed a DOAC (7 minor; 1 major) and 14 in those prescribed warfarin (12 minor;
2 major). Weight in kg (p<0.001), BMI (p=0.013) and HAS-BLED score (p=0.035) were
predictive of a first bleeding event in patients prescribed warfarin. The odds ratio
for any type of bleed on DOAC vs warfarin was 0.55 (0.180-1.681; 95% CI).
Conclusions
In patients with atrial fibrillation and class III obesity, regarding safety, DOACs
appear to be non-inferior to warfarin during the first six to 12 months of therapy
in our rural population – consistent with other analyses; however, the lack of thrombosis
events limited the efficacy analysis.
Key Indexing Terms
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Article info
Publication history
Published online: January 21, 2023
Accepted:
January 16,
2023
Received:
May 22,
2022
Publication stage
In Press Journal Pre-ProofIdentification
Copyright
© 2023 Southern Society for Clinical Investigation. Published by Elsevier Inc. All rights reserved.
