An observational study in Ischemic Stroke and Anticoagulant Adverse Reaction, sponsored by National Taiwan University Hospital. Recruiting at 1 site in Taiwan. Open to participants aged 20 Years and older. Per ClinicalTrials.gov, last updated 2023-11-28.
Sponsored by National Taiwan University Hospital · Observational
Non-vitamin K antagonist oral anticoagulants (NOACs) are recommended over warfarin in preventing stroke and thromboembolism among patients with atrial fibrillation (AF) in several guidelines. To evaluate the pharmacological effects of NOACs, directly measuring the concentration is the most arbitrary way since the correlation between concentration and common coagulation tests are not reliable. Our previous investigation reported under the fixed dose regimen, dabigatran exposure increased in elderly, renal impairments and patients with multiple co-morbid conditions. Our data also showed difference in NOACs exposure in Asians. For example, patients under rivaroxaban, in comparison to apxiaban, were more likely to have lower than expected range drug level. Furthermore, the NOACs concentration also affected by the prescription pattern of physicians (non-compliant to labeled dose) and patients' behavior (poor medication adherence).
The relationship between NOACs exposure and safety has been elucidated in large-scale clinical trials. As the NOACs level increased, the risk for bleeding increased, too. Nevertheless, no additional protection was noted with increased NOACs levels. In post marketing surveillance, bleeding and thrombotic events have been reported. Investigating the NOACs level among these patients helps evaluating the residual drug in the body, which could be a reference for clinical decision in emergent situation.
Specific purpose: Investigate the correlation between NOACs concentration upon the arrival of emergency department (ED) and important clinical outcomes including systemic thromboembolism, and major bleeding.
Direction for investigation:
Non-vitamin K antagonist oral anticoagulants (NOACs) are recommended over warfarin in preventing stroke and thromboembolism among patients with atrial fibrillation (AF) in several guidelines. To evaluate the pharmacological effects of NOACs, directly measuring the concentration is the most arbitrary way since the correlation between concentration and common coagulation tests are not reliable. Our previous investigation reported under the fixed dose regimen, dabigatran exposure increased in elderly, renal impairments and patients with multiple co-morbid conditions. Our data also showed difference in NOACs exposure in Asians. For example, patients under rivaroxaban, in comparison to apxiaban, were more likely to have lower than expected range drug level. Furthermore, the NOACs concentration also affected by the prescription pattern of physicians (non-compliant to labeled dose) and patients' behavior (poor medication adherence).
The relationship between NOACs exposure and safety has been elucidated in large-scale clinical trials. As the NOACs level increased, the risk for bleeding increased, too. Nevertheless, no additional protection was noted with increased NOACs levels. In post marketing surveillance, bleeding and thrombotic events have been reported. Investigating the NOACs level among these patients helps evaluating the residual drug in the body, which could be a reference for clinical decision in emergent situation.
Specific purpose:
Prospectively record the NOACs concentration among AF patients under NOACs therapy and suffered from IS, TIA, ICH or major bleeding.
AF patients who presented to emergent department (ED) for acute IS, TIA, ICH (non-traumatic), or other major bleeding and was under NOACs therapy will be recruited to this study. Blood sample will be collected before acute management to measure NOACs concentration. Co-morbid disease, laboratory tests and concurrent medications will be retrieved from electronic medical records. The onset, location, severity of IS. ICH or other major bleeding, and the outcome and long-term managements will be prospectively recorded.
Investigate the correlation between NOACs concentration and thromboembolic or bleeding events.
For each NOACs, we are going to compare the differences in NOACs exposure between patients with thromboembolism or major bleedi. Important baseline characteristics, co-medications and disease severity will be adjusted before making comparison.
From the data of NOACs concentration among patients with IS or ICH, we plan to propose a therapeutic range with acceptable efficacy and safety for NOACs therapy. Our data will provide a guide for physicians to make important clinical decision.
7,286 studies on the registry are indexed under Stroke; 2,007 are open to participants now.
This study's planned enrollment of 1,000 is above the median of 160 across 1,692 observational studies indexed under Stroke.
Browse Stroke studies →National Taiwan University Hospital is the lead sponsor of 2,563 studies on the registry; 569 are open to participants now.
Of its 11 completed or terminated interventional studies of FDA-regulated products, 2 (18%) have results posted.
Counted across the registry records on this site, refreshed daily.
Patient under direct oral anticoagulant therapy and suffered from ischemic stroke or intracranial hemorrhage.
Exclusion Criteria:
For patients who received direct oral anticoagulants (DOAC) before ischemic stroke or intracranial hemorrhage, the DOAC level upon hospital arrival will be measured.
Also known as: Direct oral anticoagulants
Functional outcome
Functional status measured by using the modified Rankin Scale.
Time frame: 3 months after stroke (ischemic or hemorrhagic)
Symptomatic intracranial hemorrhage (sICH)
Type 2 parenchymal hemorrhage on the follow-up neuroimage in 24 to 36 hours after EVT, with neurological deterioration of ≥4 points on the National Institute of Health Stroke Scale (NIHSS) score from baseline
Time frame: 24-36 hours after stroke
Early neurological improvement
Reduction of 8 points or more in the NIHSS score within 24 hours.
Time frame: 24 hours after stroke
Successful reperfusion (in ischemic stroke patients receiving endovascular thrombectomy)
Defined as Thrombolysis in Cerebral Infarction (TICI) scale 2b to 3
Time frame: Evaluated after EVT
Recurrent ischemic stroke
Neurological symptoms with ischemic lesion noted on neuroimaging
Time frame: 3 years
Recurrent intracranial hemorrhage
Neurological symptoms with hemorrhagic lesion noted on neuroimaging
Time frame: 3 years
Plan to share: No
No publications or documents are linked to this record.
Eligibility is decided by the study team. Share this record with your doctor or contact the team directly.
Contact study teamGet an email when the registry record changes — status, dates, results — or when someone posts here.
Sign in to followQuestions and observations about this study, from anyone following it. Not medical advice, and not a channel to the study team — their contact details are on the registry record.
Sign in to join the discussion. Reading takes no account; posting does. You choose a display name, and a pseudonym is the default.
Nothing here yet. If you are running this trial, taking part in it, or weighing whether to, this is the place to say so.
National Taiwan University Hospital