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Updated: Jun 23, 2026
08:01
The Nijmegen Hemostasis Assay: Simultaneous Fluorogenic Measurement of Thrombin and Plasmin Generation in a Single Well
Published on: February 27, 2026
Thrombin generation and coagulation factor activities: evaluation and comparison with the international normalized
Thomas D Christensen1, Claus Jensen, Torben B Larsen
1Department of Cardiothoracic and Vascular Surgery and Institute of Clinical Medicine, Aarhus University Hospital, Skejby, Denmark. tdc@ki.au.dk
Summary
Calibrated automated thrombin generation (CAT) and coagulation factor activities did not show significant variability over time in patients on oral anticoagulation therapy. These measures were associated with INR but did not provide additional biological variation insights.
Area of Science:
- Hematology
- Clinical Chemistry
- Pharmacology
Background:
- Oral anticoagulation therapy (OAT) monitoring relies on the International Normalized Ratio (INR).
- INR's effectiveness in predicting OAT-related complications is debated.
- More sensitive biomarkers for OAT monitoring have been proposed.
Purpose of the Study:
- To assess the variability of calibrated automated thrombin generation (CAT) and clotting activity of coagulation factors II, VII, IX, and X.
- To determine the association between CAT, factor activities, and INR.
- To compare INR measurements from central labs and portable coagulometers.
Main Methods:
- Prospective study of 24 patients on stable coumarin therapy for 6 weeks.
- Utilized a mixed-effects model for statistical analysis.
- Measured CAT and coagulation factor activities alongside INR (central lab and portable devices).
Main Results:
- CAT and coagulation factor activities exhibited stable variability over the study period.
- Approximately 50% of CAT and factor activity variability correlated with INR variations.
- Significant associations were found between CAT, factor activities, and INR, but within-patient variation remained.
Conclusions:
- CAT and coagulation factor activities may not offer additional insights into biological variation during OAT.
- Larger clinical studies are required to evaluate their predictive value for complications in individual patients.
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