Abstract Number: PB2451
Meeting: ISTH 2020 Congress
Theme: Venous Thromboembolism and Cardioembolism » VTE Treatment
Background: Availability of tests for measuring levels of direct oral anticoagulant (DOAC) is increasing in hemostasis laboratories and may be useful for patient management in several clinical situations, namely bleedings, thrombosis or before urgent invasive procedures, as some studies point out that DOAC levels can correlate with thrombotic or hemorrhagic events.
Aims: We aim to assess the usefulness of the DOAC concentration levels and actions taken after the concentration results.
Methods: .We performed a retrospective analysis including all the DOAC level measurements during 2019 at our hospital. We recorded age, gender, DOAC level, indication for anticoagulation and reasons for checking DOAC levels and actions taken upon.
Results: A total of 514 tests were performed in 434 patients. Patient characteristics according to their anticoagulant therapy are shown in table 1. The main reason for anticoagulation was atrial fibrillation (76.5%). The main reasons for level monitoring were bleeding, urgent invasive procedures or surgery and thrombosis (40.6%,33.6%,12.0%)..
As Figure 1 shows, there are significant differences in drug concentrations when comparing different clinical decisions. Patients who needed DOAC reversal agents had higher concentration levels.
When analyzing each DOAC, no significant differences were found in the therapeutical approach after assessment of DOAC level. Patients without clear indication for DOAC levels evaluation had fewer changes in their therapy (dose or change).
Patients with history of chronic kidney disease (CKD) showed similar drug concentration levels as those without CKD. Patients with acute kidney injury (AKI), when compared with those without AKI, had higher DOAC concentrations (median level 123vs.73ng/mL), were more frequently given reversal agents (26.8vs.17.0%), and resume anticoagulation less frequently (2.4vs.12.4%).
Conclusions: The evaluation of DOAC levels, integrated into the patient´s clinical situation, can be useful in the decision to manage anticoagulation, in different clinical scenarios. CKD does not interfere with DOAC levels, unlike AKI which greatly increases DOAC levels.
| Variable | Apixaban n=186 | Dabigatran n=86 | Edoxaban n=44 | Rivaroxaban n=118 |
| Gender, male, n (%) | 75 (40.3) | 45 (52.3) | 27 (61.4) | 59 (28.6) |
| Age, years, median [IQR] | 81 [77.0;86.0] | 81 [74.0;87.0] | 74 [67.3;83.7] | 79 [71.5;84.0] |
| Drug level, median [IQR] | 122.5 [52.8; 225.8] | 117 [38.8; 236.3] | 61 [20.0; 122.8] | 38 [25.0; 129.0] |
| Motive – bleeding n (%) | 71 (38.2) | 34 (39.5) | 23 (52.3) | 48 (40.7) |
| Motive – thrombosis, n (%) | 16 (8.6) | 14 (16.3) | 4 (9.1) | 18 (15.3) |
| Motive – urgent Invasive procedures and surgery n (%) | 72 (38.7) | 23 (26.7) | 10 (22.7) | 41 (34.7) |
| Reversal of DOAC, n (%) | 43 (23.2) | 13 (15.7) | 6 (14.3) | 17 (14.7) |
| Chronic kidney disease, n (%) | 37 (19.9) | 12 (14.0) | 5 (11.4) | 18 (15.3) |
| Acute kidney injury, n (%) | 38 (20.4) | 16 (18.6) | 8 (18.1) | 21 (17.8) |
[Table 1 – Characteristics of the population according to the prescribed DOAC]
[Fig1 – Median and 95% CI of the DOAC level for each therapeutic decision. Connecting lines represent p<0.05 between two groups.]
To cite this abstract in AMA style:
Martins Pereira F, Machado I, Teixeira AP, Ricca Gonçalves L, Carvalho M, Koch C. Concentration Levels of Direct Oral Anticoagulants and Clinical Relevance in a Tertiary Hospital [abstract]. Res Pract Thromb Haemost. 2020; 4 (Suppl 1). https://abstracts.isth.org/abstract/concentration-levels-of-direct-oral-anticoagulants-and-clinical-relevance-in-a-tertiary-hospital/. Accessed September 22, 2023.« Back to ISTH 2020 Congress
ISTH Congress Abstracts - https://abstracts.isth.org/abstract/concentration-levels-of-direct-oral-anticoagulants-and-clinical-relevance-in-a-tertiary-hospital/