engleski

Comparison of D-dimer values at peak and trough concentrations of direct oral anticoagulants: result of D-dimer testing is not affected by plasma drug concentration

Background: Knowledge of the Effect of Direct Oral Anticoagulants (DOACs) Concentration in Plasma on D-dimer Values Has so far Been Insufficiently Examined Aims: To investigate whether plasma concentration (peak vs. trough) of DOACs (dabigatran, rivaroxaban and apixaban) affects D-dimer values. Methods: The study included a total of 218 plasma samples including peak (N=109) and trough (N=109) DOACs levels in outpatients treated with standard drug doses (dabigatran N=35, 2×150 mg/day, rivaroxaban N=37, 1×20 mg/day and apixaban N=37, 2×5 mg/day) in steady-state and obtained during their regular clinical examination. Blood samples were taken on the same day to obtain both trough (immediately prior the next drug dose) and peak (two hours after drug administration) DOACs concentrations. Rivaroxaban and apixaban concentrations were determined using chromogenic anti-FXa assay (Innovance heparin, Siemens Healthineers, Germany) with drug specific calibrators (Hyphen Biomed, France). Dabigatran was measured using Innovance DTI assay (Siemens Healthineers, Germany). D-dimer concentration was determined by quantitative particle-enhanced immunoturbidimetric assay using monoclonal antibody (Innovance D-dimer, Siemens Healthineers, Germany). All measurements were performed on BCSXP analyzer (Siemens Healthineers, Germany). Statistical analysis was done using Wilcoxon test by MedCalc Statistical Software version 11.5.1. The study was funded by the Croatian Science Foundation as part of the research project IP-2016-06-8208. Results: Concentrations of DOACs have shown significant differences between peak and trough levels (P<0.001) for all three DOACs (Figure 1). On the contrary, concentrations of D-dimer did not show significant differences in samples with peak and trough concentrations of all three DOACs drugs (P=0.852, P=0.274 and P=0.833), as shown in Figures 1 and 2. Conclusions: Concentration of DOACs in plasma does not affect D-dimer values. Our results clearly indicate that D-dimer testing can be performed at any time point in patients treated with all three DOACs without effect of drug concentration in plasma on the D-dimer test result.

D-dimer testing ; DOACs

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