PB0027 - Time to Bleeding After DOAC initiation for Venous Thromboembolism or Atrial Fibrillation

Sunday, June 23, 2024

13:45 – 14:45 ICT

Room: Exhibition Hall

Co-Author(s)

SZ

Sofia Zestos

Research Assistant
Division of Cardiovascular Medicine, Department of Internal Medicine, University of Michigan, Ann Arbor, MI
Ann Arbor, Michigan, United States
JE

Josh Errickson

Statistician
Consulting for Statistics, Computing and Analytics Research, University of Michigan, Ann Arbor, MI
Ann Arbor, Michigan, United States
XK

Xiaowen Kong

Statistical Analyst
Division of Cardiovascular Medicine, Department of Internal Medicine, University of Michigan, Ann Arbor, MI
Ann Arbor, Michigan, United States
MA

Mona A. Ali

Pharmacist
Department of Heart and Vascular Services, Corewell Health William Beaumont University Hospital, Royal Oak, MI
Royal Oak, Michigan, United States
CG

Christopher Giuliano

Pharmacist
Department of Pharmacy Practice, Eugene Applebaum College of Pharmacy and Health Science, Wayne State University, Detroit, MI
Detroit, Michigan, United States
BH

Brian Haymart

Project Manager
Division of Cardiovascular Medicine, Department of Internal Medicine, University of Michigan, Ann Arbor, MI
Ann Arbor, Michigan, United States
Scott Kaatz, DO, MSc

Co-director, Anticoagulation Clinics
Division of Hospital Medicine; Anticoagulation Services, Henry Ford Health, Detroit, MI
Detroit, Michigan, United States
DD

Deborah DeCamillo

Project Manager
Division of Cardiovascular Medicine, Department of Internal Medicine, University of Michigan, Ann Arbor, MI
Ann Arbor, Michigan, United States
NR

Noelle Ryan

Pharmacist
Division of Hospital Medicine; Anticoagulation Services, Henry Ford Health, Detroit, MI
Detroit, Michigan, United States
SS

Suman L. Sood

Associate Professor
Division of Hematology/Oncology, Department of Internal Medicine, University of Michigan, Ann Arbor, MI
Ann Arbor, Michigan, United States
TT

Twylla Tassava

Hospitalist
Department of Internal Medicine, Trinity Health, Ypsilanti, MI
Ypsilanti, Michigan, United States
JF

James B. Froehlich

Professor
Division of Cardiovascular Medicine, Department of Internal Medicine, University of Michigan, Ann Arbor, MI
Ann Arbor, Michigan, United States
Geoffrey Barnes, MD, MSc

Cardiologist and Vascular Medicine Specialist
University of Michigan
Ann Arbor, Michigan, United States

Presenting Author(s)

Jordan K. Schaefer, MD, MSc

Associate Professor
Division of Hematology/Oncology, Department of Internal Medicine, University of Michigan, Ann Arbor, MI
Ann Arbor, Michigan, United States

Background: Oral anticoagulation increases bleeding risk, especially after initiation. In a non-trial setting it is unclear how bleeding risk varies by time and indication with the direct oral anticoagulants (DOACs).

Aims: To compare bleeding rates after DOAC initiation for non-valvular atrial fibrillation (AF) and venous thromboembolism (VTE).

Methods: Within the Michigan Anticoagulation Quality Improvement Initiative (MAQI2), we analyzed monthly bleeding rates for newly initiated DOAC treated patients within four anticoagulation clinics. We compared non-major bleeding, major bleeding, and all bleeding rates by indication for AF or VTE. Patients with both AF and VTE and with no follow-up visits were excluded. Event rates were compared by Poisson test and proportion test using R 64-4.1.3.

Results: 1,919 AF and 744 VTE patients were included (Table 1). The majority of patients were on apixaban or rivaroxaban. Patients with VTE experienced 109.7 versus 54.8 bleeding events/100 patient years in month one compared to month two (p=0.001), with a significant decline in event rates over time (p < 0.001). Major bleeding also decreased significantly over time (Figure 1, p=0.008). Patients with AF experienced 65.7 versus 43.1 bleeding events/100 patient years in month one compared to month two (p=0.008), with a significant decline in event rates over time (p < 0.001). However, major bleed rates did not significantly change over time. Patients with VTE had higher bleeding event rates compared to AF, with event rates highest the first month (109.7 versus 65.7 events/100 patient years for VTE and AF in month 1, p=0.001) and then declining over time (Figure 1, 26.8 versus 17.9 events/100 patient years for VTE and AF over months 1-12, p=0.045).

Conclusion(s): Bleeding rates are highest in the initial three months of oral anticoagulation. Clinicians should address modifiable bleeding risk factors and ensure close follow-up after starting DOACs.