PB0447 - Adherence and persistence to Direct Oral Anticoagulants (DOACs) in the community following newly diagnosed Venous Thromboembolism (VTE) – a pharmacy-linkage study

Sunday, July 10, 2022

6:30 PM – 7:30 PM

Location: Exhibition

Presentation Format: In-Person

Presenting Author(s)

Caroline Dix, MBBS, MSc, FRACP, FRCPA

Haematology Fellow
The Alfred Hospital, Melbourne
Melbourne, Victoria, Australia

Co-Author(s)

HB

Hadley Bortz

Senior Anticoagulation Stewardship Pharmacist
Pharmacy Department, The Alfred Hospital
Melbourne, Victoria, Australia
Md

Mike da Gama

Data Analyst
NostraData
Melbourne, Victoria, Australia
MT

Michael Treloar

Data Analyst
NostraData
Melbourne, Victoria, Australia
MR

Michael Reynolds

Data Analyst
NostraData
Melbourne, Victoria, Australia
TD

Thomas Day

Haematologist
Department of Haematology, Flinders Medical Centre
Adelaide, South Australia, Australia
HT

Huyen Tran

Professor
Australian Centre for Blood Diseases, Monash University
Melbourne, Victoria, Australia

Background: Adherence to medications is a clinical concern across many chronic illnesses. Adherence and persistence to DOACs for VTE is critical to ensure adequate treatment of the thrombosis and, if used for an extended duration, to prevent new VTE episodes.

Aims: Assess the adherence and persistence to DOACs in patients in the community following admission to hospital with a new VTE.

Methods: We retrospectively reviewed community pharmacy dispensing data on all patients with newly diagnosed VTE and prescribed a DOAC (apixaban or rivaroxaban) between January 2018 and December 2019 at our institution. Proportion of days covered (PDC) was used to assess adherence at 90 days, and 6- and 12-months. Persistence was measured by participants having a dispensed supply of DOAC at the end of the intended treatment period, as long as there were no significant gaps in supply (>60 days). Ethics approval was granted

Results: We identified 225 patients who met inclusion criteria. Overall PDC at 90 days, 6months and 12 months were 84.6%, 86.2% and 86.1% respectively. Apixaban had a higher mean PDC than rivaroxaban, at 86.2% and 80.6% respectively (P < 0.01). Females had a higher PDC than males, 87.3% and 81.2% respectively (p < 0.05). 133 (64%) were persistent with therapy and there were no clinical predictors of improved persistence.

Conclusion(s): In patients with newly diagnosed VTE treated with a DOAC, adherence rates were high at over 80%, with females and those prescribed apixaban having higher adherence. Only two-thirds were persistent with therapy for the intended treatment duration. These findings may assist clinicians in potentially identifying those at risk of poor adherence.