Atrial Fibrillation
Conditions
Keywords
atrial fibrillation, stroke, warfarin, aspirin
Brief summary
Current guidelines recommend standard warfarin anticoagulation international normalized ratio (INR) goal of 2.0-3.0 in adults with non valvular atrial fibrillation (NVAF). The investigators hypothesized that low-intensity warfarin (INR 1.5-2.0) has the same effectiveness and better security in elderly patients (\>75) with NVAF.
Detailed description
Atrial fibrillation is the commonest chronic arrhythmia in clinical practice, especially in octogenarians. Nonvalvular atrial fibrillation increases the risk of ischemic stroke by approximately 5-fold and these strokes result in higher mortality and disability. Warfarin is recommended as first line anticoagulation treatment in patients with NVAF who are at moderate or high risk of stroke,while antiplatelet agents, such as aspirin, give a more convenient but less effective alternative in the prevention of ischemic stroke and are recommended in low risk patients.Current guideline about warfarin anticoagulation therapy recommend that target INR value must be maintained between 2.0 and 3.0,which not only reduces the frequency of ischaemic stroke but also its low incidence of major bleeding. However, the current status of anticoagulation therapy for elderly Chinese AF patients, particularly in aged over 80 years, is not clear. The purpose of the present study was to test the hypothesis that an INR target of 1.5-2.0 can provide the same efficacy and better safety as compare with a standard target of 2.0-3.0 in patients over 75 with NVAF.
Interventions
DRUGWarfarin
Patients randomised to receive warfarin were initiated on treatment at the baseline dose of 1.25mg daily and then gradually increase the amount to the target INR range.
DRUGaspirin
100mg aspirin was administrated every day
Sponsors
Nanjing Medical University
Study design
Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
TREATMENT
Masking
SINGLE (Outcomes Assessor)
Eligibility
Sex/Gender
ALL
Age
75 Years to 94 Years
Healthy volunteers
Yes
Inclusion criteria
1. Clinical diagnosis of atrial fibrillation 2. Echocardiography confirmed a non-valvular heart disease 3. Age≥75 years
Exclusion criteria
1. Unable to cooperate with doctors 2. Life expectancy of less than 1 year 3. Rheumatic heart disease or dilated cardiomyopathy 4. History of artificial valve replacement surgery 5. Infectious endocarditis 6. Stroke or transient ischemic attack(TIA) within the last 6 months 7. Previous history of intracranial hemorrhage, gastrointestinal, respiratory or urogenital bleeding 8. Previous intolerance/allergy to warfarin or aspirin 9. Blood pressure greater than 180/110 mmHg 10. Chronic liver dysfunction, alanine aminotransferase above the normal reference value of the upper limit 3 times 11. Chronic renal failure, serum creatinine clearance rate (Ccr) less than 30 ml / min 12. Patient was receiving antiplatelet or anticoagulant therapy due to other reasons
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| major haemorrhage | 2 years | Major haemorrhage was defined as intracranial hemorrhage, gastrointestinal bleeding, bleeding requiring hospitalization and surgical intervention, a reduction of hemoglobin by≥2 g/dL, requiring red blood cells transfusion ≥2 units. Follow-up study visits were scheduled for once a week in the first month and then every 3 months. The number and results of INR tests, liver and kidney function tests were recorded. In addition, the number of bleeding events was recorded. |
| ischaemic stroke | 2 years | ischaemic stroke was defined as a blockage in an artery that supplies blood to the brain , resulting in a deficiency in blood flow and focal neurological deficit lasting \>24 hours. Follow-up study visits were scheduled for once a week in the first month and then every 3 months. The number and results of INR tests, liver and kidney function tests were recorded. In addition, the number of ischaemic stroke was recorded. |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| deep vein thrombosis | 2.5 years | Deep vein thrombosis (DVT) was defined as a blood clot in a major vein that usually develops in the legs and/or pelvis and blocks blood flow, which can be diagnosised by ultrasound. Follow-up study visits were scheduled for once a week in the first month and then every 3 months. The number and results of INR tests, liver and kidney function tests were recorded. The number of deep vein thrombosis was recorded. |
| minor bleeding | 2.5years | Minor bleeding was any other bleeding requiring modification of the antithrombotic regimen,such as hematuria, gingival, conjunctival bleeding and so on. Follow-up study visits were scheduled for once a week in the first month and then every 3 months. The number and results of INR tests, liver and kidney function tests were recorded. In addition, the number of minor bleedinge was recorded. |
| cardiovascular death | 2.5 years | Cardiovascular causes of death included myocardial infarction, heart failure, cardiac arrhythmia. Follow-up study visits were scheduled for once a week in the first month and then every 3 months. The number and results of INR tests, liver and kidney function tests were recorded. The number of cardiovascular death was recorded. |
| pulmonary embolism | 2.5 years | Pulmonary embolism was defined as occurrence of typical shortness of breath, chest pain, D-dimer and CT pulmonary angiography abnormalities. Follow-up study visits were scheduled for once a week in the first month and then every 3 months. The number and results of INR tests, liver and kidney function tests were recorded. The number of pulmonary embolism was recorded. |
| myocardial infarction | 2.5 years | Myocardial infarction was defined as occurrence of typical chest pain, ECG and cardiac enzyme abnormalities. Follow-up study visits were scheduled for once a week in the first month and then every 3 months. The number and results of INR tests, liver and kidney function tests were recorded. The number of myocardial infarction was recorded. |
Countries
China
Outcome results
None listed