High Fluctuation Between Anticoagulants, Frequent Off-Label Dosing, and No Difference Concerning Outcomes: Results of a Real-Life Cohort Study - Eschler, C. M.; Antelo, A.; Funk, G. C.; Exadaktylos, A. K.; Lindner, G. (Am J Med, 2021)
BACKGROUND: Recently published studies indicated a high proportion of patients taking direct oral anticoagulants (DOACs) are off-label under- or overdosed. The present study aimed at investigating whether off-label dosages are corrected over time and whether off-label doses are associated with differences in bleeding rates, ischemic stroke, or venous thromboembolism. METHODS: In this retrospective cohort study, patients presenting to our emergency department between January 1 and December 31, 2018, with therapeutic oral anticoagulation were included (ie, vitamin-K antagonists [VKAs], rivaroxaban, apixaban, edoxaban, and dabigatran) and follow-up for a maximum of 2 years until December 31, 2019, was made. Detailed chart reviews were performed for each case concerning characteristics, indication, bleeding complications, or changes in the used substance or dosage. RESULTS: We reviewed 2588 consultations of 1228 patients receiving therapeutic oral anticoagulation. During the maximum follow-up period of 2 years vitamin K antagonists and rivaroxaban lost the largest proportions in favor of apixaban. The overall distribution of dosage correctness remained almost unimproved (correct dosing in 62.5%, underdosing in 23.6%, coverdosing in 13.9%).The corresponding outcomes did not differ with respect to bleeding events, ischemic stroke, or venous thromboembolism among various anticoagulants as well as between correct and off-label doses. CONCLUSIONS: A rising proportion of existing oral anticoagulation regimes was changed to apixaban, while the proportion of off-label dosages of all oral anticoagulants remained stable. No difference in bleeding rates, de novo strokes, or thromboembolisms was found between anticoagulants as well as between correct and off-label doses.
Keywords: journalArticle; Administration, Oral; Aged; Aged, 80 and over; Anticoagulants/*administration & dosage; Anticoagulation; Bleeding, Direct oral anticoagulant (DOAC); Cohort Studies; Dosage; Female; Hemorrhage/*epidemiology; Humans; Ischemic Stroke/*epidemiology; Male; Off-Label Use/*statistics & numerical data; Retrospective Studies; Treatment Outcome; Venous Thromboembolism/*epidemiology