Results of the International Survey on Adherence with Anticoagulation in Children, Adolescents and Young Adults
Authors: Thornburg Courtney D , Todd Kevin E , Mcgrady Meghan E , Ignjatovic Vera , Jones Sophie , Rizzi Mattia , Luchtman-Jones Lori 
Published: November 2021

Abstract
Introduction
Children, adolescents, and young adults are prescribed chronic anticoagulation with oral and parenteral medications for treatment and prevention of thrombosis. Non-adherence to the recommended dosing, schedule, and monitoring of anticoagulants may lead to poor treatment outcomes. Considering that little is known about adherence to anticoagulation in children, this survey aimed to evaluate provider practices and experiences related to pediatric, adolescent, and young adult patient adherence with anticoagulation.
Methods
A REDCap ® survey was developed by members of the International Haemostasis and Thrombosis Pediatric and Neonatal Scientific Subcommittee Medication Adherence Working Group. Questions regarding current clinical practices related to medication adherence (i.e., assessment, barriers to addressing adherence) were developed by the multi-disciplinary working group with expertise in anticoagulation, medication adherence, and hematology research. The survey was distributed in electronic form to more than 500 clinicians through the International Society of Haemostasis and Thrombosis plus related professional organizations in the United States, Switzerland, New Zealand, and Australia. Clinicians are eligible for the study if they are involved in anticoagulation management in children and/or adolescents and young adults.
Results
A total of 112 clinicians completed surveys. The majority (n = 104 , 93%) were pediatric hematology/oncology physicians. Demographic and clinical practice characteristics are shown in Table 1. Ninety-nine (88%) respondents reported that medication adherence is typically assessed for patients in their practice prescribed anticoagulation. Details regarding medication adherence clinical practices are shown in Table 2. Forty-eight (43%) reported that they often or always worry about medication adherence in patients prescribed anticoagulation. While most clinicians (n = 83, 74%) reported they are often or always confident in addressing non-adherence, only 30% (n = 34) reported that they are often or always confident about identifying patients who are non-adherent and only 50 (45%) reported that they often or always have the resources to effectively address non-adherence. Fifty-five (49%) respondents indicated that they had cases where non-adherence resulted in new or recurrent thrombosis and 20 (18%) indicated that they had cases where non-adherence resulted in bleeding. In response to the free text question: "What types of resources would make it easier to measure adherence in your clinic?," themes emerged regarding tools (i.e., validated instruments and electronic apps to measure adherence), communication with pharmacy, and more time and staffing in clinic. When asked: "When you identify a patient/family who is struggling to take their anticoagulation as prescribed or follow-up with labs or appointments for anticoagulation, what do you do?," clinicians discussed identification of barriers; education; involving additional staff including nursing, social work, and pharmacy; consider switching anticoagulation; increase frequency of calls, clinic visits and/or labs; and use of reminders. Some providers reported utilizing shared decision-making or motivational interviewing to improve adherence.
Conclusions
Clinicians who prescribe anticoagulation for children, teens, and young adults identify medication non-adherence as a clinically significant issue that may result in recurrent thrombosis or bleeding. Clinicians perceive that non-adherence most often occurs when patients skip doses and/or do not follow monitoring recommendations. Current gaps in clinical practice include resources to identify patients who are non-adherent and strategies to improve adherence. A multi-disciplinary team including nurses, physicians, pharmacists, social workers, and psychologists who have dedicated time for anticoagulation management could potentially improve outcomes for children prescribed anticoagulation. As direct oral anticoagulants are approved for children and adolescents, the impact on medication adherence with these treatment options should be evaluated.
Figure 1 Figure 1.

Disclosures
Thornburg: HemaBiologics: Honoraria; CSL Behring: Honoraria; Octapharma: Honoraria; Biomarin: Honoraria, Research Funding; Genentech: Honoraria; Bluebird Bio: Other: data safety monitoring board; Ironwood Pharmaceuticals: Other: data safety monitoring board.