Adherence to Antithrombotic Therapy for Patients Attending a Multidisciplinary Thrombosis Service in Canada – A Cross-Sectional Survey

Kwadwo Osei Bonsu,1 Stephanie Young,1,2 Tiffany Lee,1,2 Hai Nguyen,1 Rufaro S Chitsike3,4 1School of Pharmacy, Memorial University of Newfoundland and Labrador, St John’s, NL, A1B 3V6, Canada; 2Pharmacy Program, Eastern Region Health Authority, St John’s, NL, A1B 3V6, Canada; 3Division of Medicine (Hematology), Memorial University of Newfoundland and Labrador, St John’s, NL, A1B 3V6, Canada; 4Division of Hematology, Eastern Region Health Authority, St John’s, NL, A1B 3V6, CanadaCorrespondence: Kwadwo Osei Bonsu, School of Pharmacy, Memorial University of Newfoundland and Labrador, 300 Prince Philip Drive, St John’s, NL, A1B 3V6, Canada, Email [email protected]: Poor medication adherence puts patients who require antithrombotic therapy at greater risk of complications. We started a multidisciplinary Adult Outpatient Thrombosis Service in 2017 in a Canadian health authority and were interested in the level of medication adherence in the population attending.Aim(S): The aim of this study is to assess adherence to antithrombotic medications for patients attending a multidisciplinary Thrombosis Service.Methods: We conducted a cross-sectional survey of outpatients seen at the Thrombosis Service between 2017 and 2019 using the 12-item validated Adherence to Refills and Medications Scale (ARMS) to assess adherence to antithrombotic (anticoagulants and antiplatelet) therapy. Linear regression analysis examined the factors associated with adherence to antithrombotic therapy.Results: Of 1058 eligible patients, 53.2% responded to the survey. Seventeen were excluded from the analysis for missing more than 6 responses to the 12 items on the ARMS. About 55% (n = 297) were on direct oral anticoagulants (DOACs), 19% (n = 102) on warfarin, 5.0% (n = 27) on low molecular weight heparin, 3.3% (n = 18) on antiplatelet therapy and 18% (n = 96) were no longer on antithrombotic therapy. Nearly half (47%, n = 253) had taken antithrombotic therapy for 1– 5 years while 28% (n = 150) and 25% (n = 137) had taken antithrombotic treatments for 5 years, respectively. Most patients (87%, n = 475) were ≥ 50 years and half (51%, n = 277) were male. The mean adherence score was 13.9 (SD± 2.2) and 88% (n = 481) of participants were adherent to antithrombotic treatment (ARMS = 12– 16). Multivariable linear regression showed that patients with post-graduate education had 0.4% lower adherence to antithrombotic therapy as compared with elementary education (β = 0.0039, p = 0.048). Patients with prior antithrombotic agent use > 5 years had 0.5% lower adherence to antithrombotic treatment compared to patients with < 1 year (β = 0.0047, p = 0.0244).Conclusion: Self-reported adherence to antithrombotic therapy was high (88%) within a multidisciplinary Thrombosis Service. Patients with advanced education and prolong duration of antithrombotic therapy were more likely to have lower self-reported adherence to antithrombotic treatment.Keywords: medication adherence, self-reported adherence, multidisciplinary care, thrombosis service, anticoagulation management program, antithrombotic therap

Prevention and treatment of the post-thrombotic syndrome and of the chronic thromboembolic pulmonary hypertension

none2noPost-thrombotic syndrome (PTS) and chronic thromboembolic pulmonary hypertension (CTEPH) are late complications of venous thromboembolism. The purpose of this review is to present and discuss recently published studies that have improved our knowledge of PTS and CTEPH. The current understanding of the pathophysiology of PTS and CTEPH is discussed as well as the importance of chronic residual venous thrombosis, some polymorphisms of plasminogen activator inhibitor-1, and the current concept of misguided thrombus resolution. The surprising finding that elastic compression stockings may not be effective in preventing PTS and the novel medical treatment in CTEPH are discussed in detail. Novel direct oral anticoagulants show potential for prevention of PTS. No firm conclusions can be drawn on the efficacy of elastic stockings. Novel treatments of CTEPH for inoperable patients and those with persistent pulmonary hypertension after surgery have become available and further research on wider indication for their use is urgently needed.nonePesavento, Raffaele; Prandoni, PaoloPesavento, Raffaele; Prandoni, Paol