Kidney Week

Abstract: SA-PO620

Prescribing and Safety of Direct-Acting Oral Anticoagulants Compared to Warfarin in Atrial Fibrillation Patients on Chronic Hemodialysis

Session Information

• Pharmacology
  October 27, 2018 | Location: Exhibit Hall, San Diego Convention Center
  Abstract Time: 10:00 AM - 12:00 PM

Category: Pharmacology (PharmacoKinetics, -Dynamics, -Genomics)

• 1700 Pharmacology (PharmacoKinetics, -Dynamics, -Genomics)

Authors

• Davis, Estella, Creighton University School of Pharmacy, Omaha, Nebraska, United States

Estella Davis,

• Darais, Dallin, CHI Health-Creighton University Medical Center- Bergan Mercy, Omaha, Nebraska, United States

Dallin Darais,

• Bashir, Khalid, CHI Clinic, Nephrology, Omaha, Nebraska, United States

Khalid Bashir,

• Fuji, Kevin T., Creighton University School of Pharmacy, Omaha, Nebraska, United States

Kevin T. Fuji,

Background

ESRD patients on hemodialysis (HD) were excluded from safety and efficacy studies of direct-acting oral anticoagulants (DOACs) in atrial fibrillation (AF). The objective of this study was to evaluate prescribing, dose selection, and safety outcomes of DOACs compared to warfarin in AF patients on chronic HD. Secondary objectives were to evaluate major ISTH bleeding and clinically relevant non-major bleeding (CRNMB).

Methods

This was a retrospective study of AF patients on outpatient HD and oral anticoagulation (OAC) with warfarin or DOAC from April 2010-April 2016. Records were obtained from metro area CHI Health System and Dialysis Clinics Inc. Data was analyzed using descriptive statistics, ANOVA and chi-square.

Results

91 patients were included (52% male, 79% white, mean age 69). Average CHA₂DS₂Vasc was 4.6 and HASBLED was 3.8. Warfarin was the initial OAC in most patients (n=76), mean dose 29mg/week. 15 patients were initially on DOACs: apixaban 2.5mg (n=7), apixaban 5mg (n=5), dabigatran 75mg (n=2), and dabigatran 150mg (n=1). Of 14 patients whose initial OAC was switched, 12 switched to apixaban 5mg or 2.5mg. Initial apixaban was dosed appropriately in most patients (83%) compared to apixaban switches (42%) where 9 on low dose did not meet dose reduction criteria. HASBLED scores were higher in switched patients not dosed appropriately (4 vs. 3.2, p=0.156). 26 patients experienced a bleed, with significantly more bleeding in warfarin compared to DOAC (31% vs 28%, p=0.022) patients. Most major bleeds (n=7), CRNMB (n=12), and major plus CRNMB (n=1) occurred with warfarin alone. Bleeding in DOAC patients: 1 on warfarin to dabigatran 75mg (major), 1 on warfarin to apixaban 2.5mg (major), 2 on apixaban 2.5mg (CRNMB), 1 on warfarin to dabigatran 150mg (major and CRNMB), and 1 on dabigatran 150mg to apixaban 5mg (major and CRNMB).

Conclusion

More HD patients were prescribed warfarin initially and more of these patients experienced a bleed. More prescribers selected appropriate dose apixaban as the initial DOAC or switched to it as low dose when dose reduction criteria were not met. Bleeding occurred in DOAC patients with prior warfarin therapy, switching between DOACs, and maintained on the initial DOAC. Larger studies evaluating DOAC prescribing and impact on safety in AF patients on chronic HD are warranted.