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Citrated Kaolin Reaction Time on Thromboelastography 6s Identifies Bleeding-Prone Phenotypes in Older Adults with
Jin Kyung Hwang1, Su Hyun Lee2, Sung Joo Cha2
1Division of Cardiology, Department of Internal Medicine, Veterans Health Service Medical Center, (05368) #53 Jinhawngdo-ro 61 gil, Gangdong-gu, Seoul, Republic of Korea. dangtong@naver.com.
Insights
In older adults with atrial fibrillation on DOACs, prolonged citrated kaolin reaction time (CKR) measured by TEG6s is linked to a higher risk of bleeding. This finding suggests CKR may help identify patients needing closer monitoring for bleeding events.
Area of Science:
- Geriatric Medicine
- Cardiology
- Hematology
Background:
- Older adults with atrial fibrillation (AF) on direct oral anticoagulants (DOACs) face significant bleeding risks.
- Conventional clinical scores have limited ability to predict bleeding in this population.
- Thromboelastography (TEG6s) offers point-of-care hemostasis assessment, but its clinical utility for bleeding risk is unclear.
Purpose of the Study:
- To investigate the association between TEG6s parameters and bleeding events in elderly AF patients receiving DOAC therapy.
- To determine if TEG6s can improve bleeding risk stratification beyond existing clinical scores.
Main Methods:
- Prospective enrollment of 100 patients aged 75+ with non-valvular AF on DOACs.
- Baseline TEG6s measurements, including citrated kaolin reaction time (CKR).
- Bleeding events classified using International Society on Thrombosis and Haemostasis criteria; logistic regression and ROC analyses performed.
Main Results:
- 33 patients experienced clinically relevant bleeding over 1 year.
- Prolonged CKR was independently associated with increased bleeding risk (HR 1.36, p=0.005).
- CKR showed fair discriminative performance (AUC=0.712); other TEG parameters and clinical scores were not significant predictors.
Conclusions:
- Prolonged CKR is significantly associated with clinically relevant bleeding in older AF patients on DOACs.
- CKR may serve as an investigational biomarker for bleeding risk stratification in this cohort.
- Further validation in larger, multicenter studies is needed to confirm clinical utility.
Purpose:
Older adults with atrial fibrillation (AF) receiving direct oral anticoagulants (DOACs) remain at increased bleeding risk, and conventional clinical scores offer limited predictive value. Thromboelastography (TEG6s) provides point-of-care assessment of global hemostasis; however, its clinical utility remains unclear. This study investigated the association between TEG6s parameters and bleeding events in older adults with AF receiving DOAC therapy.
Methods:
We prospectively enrolled 100 patients aged ≥ 75 years with non-valvular AF receiving DOAC therapy. Baseline TEG6s parameters, including citrated kaolin reaction time (CKR), were obtained. Bleeding events were classified per International Society on Thrombosis and Haemostasis criteria. Logistic regression and receiver operating characteristic (ROC) analyses identified predictors of clinically relevant bleeding, defined as major and clinically relevant non-major bleeding.
Results:
Clinically relevant bleeding occurred in 33 patients during a 1-year follow-up. Prolonged CKR was independently associated with increased bleeding risk in multivariate analysis (hazard ratio 1.36; 95% confidence interval: 1.10-1.70; p = 0.005). ROC analysis demonstrated fair discriminative performance for CKR (area under the curve = 0.712), suggesting a potential role as a biomarker for bleeding risk stratification. Other TEG parameters and conventional clinical risk scores were not significant predictors.
Conclusion:
Prolonged CKR was significantly associated with clinically relevant bleeding events in older adults with AF receiving DOAC therapy. CKR may reflect an underlying bleeding tendency and could serve as an investigational biomarker for bleeding risk stratification. However, its clinical utility requires confirmation in larger, multicenter studies.
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