Patient-reported treatment burden: comparison between vitamin-K antagonist and non-vitamin K antagonist oral anticoagulants

Abstract Introduction Treatment burden (TB) is defined as the overall workload that maintenance or improvement of their functioning and well-being poses on patients with chronic medical conditions. A high patient-reported TB has been associated with lower adherence to treatment and increased risk of major adverse events including death. We explored the differences in patient-reported TB value and prevalence of unacceptably high TB score (≥59 points) between patients receiving vitamin K antagonist oral anticoagulants (VKA) and non-vitamin K antagonist oral anticoagulants (NOAC). Furthermore, we explored contributory factors associated with TB and the relationship between TB and quality of life (QoL) in these patients. Methods A single-centre study included consecutive adult in- and outpatients on long-term oral anticoagulation, seen at a university clinical centre a from April to June 2019, who were willing to complete the Treatment Burden Questionnaire encompassing 13 items assessing the TB associated with taking medicine, self-monitoring, laboratory assessments, medical consultations, organisational and administrative requirements, adherence to dietary and physical activity recommendations, as well as the social repercussions of the treatment. Results Of 320 enroled patients, 206 (64.4%) were taking a VKA. Atrial fibrillation was the most common indication for long-term oral anticoagulation (n=299, 93.4%). The mean TB score was significantly higher in patients on VKA versus those taking a NOAC (48.8 ±26.5 vs. 41.8 ±19.7, P= 0.014), mostly owing to significantly higher TB values for questions related to self-monitoring, including the International Normalized Ratio (INR) control (3.85±3.32 vs. 1.62±1.38, P<0.001) and diet restrictions (3.98±3.43 vs. 2.48±2.49, P<0.001) in patients taking VKA (Figure 1). In addition, these patients significantly more often reported an unacceptably high TB of ≥59 points compared with those taking NOAC (30.1% vs 18.4%, P= 0.024). Multivariable regression analysis of predictors of TB in patients taking a VKA or NOAC are presented in Table 1. Conclusion In our study, patients receiving a VKA reported significantly higher TB compared to those using NOAC, especially regarding the questions about self-monitoring (including INR control) and diet restrictions. An unacceptably high TB was also more prevalent among patients receiving a VKA. Our findings suggest that prescribing NOACs in preference to VKAs could help in decreasing the self-reported TB in patients who need oral anticoagulant therapy.