Prescriber compliance to direct oral anticoagulant labels and impact on outcomes in Thailand

Aims This study aimed to evaluate the prescriber compliance to the approved labels of direct oral anticoagulants (DOACs) and impact of appropriateness of dosing on clinical outcomes. Methods A retrospective study was conducted using simple-stratified random sampling of adult patients receiving >= 6 months of DOACs for various indications during 2013-2017 in 10 tertiary care hospitals. Patients were classified into 3 dosing groups including approved dose, underdosing and overdosing based on the Thai Food and Drug Administration-approved labels. Cox proportional hazard models were used to evaluate the impact of different dosings on thromboembolic and bleeding events. Results From 1200 patients included in the data analysis, prescribing of DOACs was consistent with the approved indications in 1130 cases (94.2%) while 70 patients (5.8%) received DOACs despite having contraindications or with off-label usage. Among 1026 cases of dosing evaluation cohort, 688 patients (67.1%) received approved doses. There were 227 (21.9%) and 110 (10.7%) cases of underdosing and overdosing, respectively. Multivariate analysis showed that underdosing was associated with an increased risk of thromboembolism 3.023 (95% confidence interval [CI]: 1.291-7.080;P =.011) while overdosing was associated with an increased risk of bleeding requiring hospitalization (adjusted hazard ratio, 3.045; 95% CI, 1.501-6.178;P =.002) and Bleeding Academic Research Consortium type 2 or more (adjusted hazard ratio, 2.196; 95% CI, 1.083-4.452;P =.029). Conclusion Prescribers' compliance to approved indications were high. However, 1/3 of DOAC prescriptions were inconsistent with approved dosing. Dosing deviation was associated with an increase in adverse clinical outcomes.

Automated summary

The study aimed to evaluate prescriber compliance to DOAC labels and the impact of dosing appropriateness on clinical outcomes. Results showed high compliance to approved indications but 1/3 of prescriptions did not adhere to approved dosing, and dosing deviation was associated with an increase in adverse clinical outcomes.