實証醫學討論會.ppt

實証醫學討論會 臨床問題 Atrial fibrillation容易造成thromboembolism, 引起stroke及一些血管栓塞的問題, 目前可以使用aspirin或warfarin來預防stroke的發生,使用哪一種預防stroke效果較好? PICO Patient: Atrial fibrillation Intervention: Anticoagulant Comparison: Antiplalet therapy Outcome: lower risk of stroke 搜尋過程: Background- atrial fibrillation 0.7% general population Prevalence increases with age Embolism of stasis-precipitated thrombi originating in the left atrial appendage Most common cause of cardioembolic stroke 16% of all ischemic strokes Overall risk of stroke among non-anticoagulated patients without prior stroke or TIA: 4% per year Increased risk of stroke in patient: Age, hypertension, prior TIA or stroke, DM, woman Both oral anticoagulants and antiplatelet agents have proven effective for stroke prevention in most patients at high risk for vascular events Aspirin: modest effect Adjusted-dose warfarin :larger effect, INR: 2~3 Guideline: Adjusted-dose warfarin for high risk for stroke Aspirin: for low risk or for cannot safely received adjusted dose warfarin Objective Non-valvular atrial fibrillation and no history of stroke or transient ischemic attack (TIA) Oral anticoagulant treatment Antiplatelet therapy Major vascular events (stroke. MI…) Search strategy Cochrane Stroke Group Trials Register (June 2006 Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library Issue 2, 2006) MEDLINE (1966 to June 2006) EMBASE (1980 to June 2006). Atrial Fibrillation Collaboration and experts working in the field to identify unpublished and ongoing trials. Selection criteria Randomized trials 8 randomized trials, including 9598 patients Long-term (more than 4 weeks) The mean overall follow up was 1.9 years/participant Chronic non-valvular af patients Adjusted-dose warfarin :INR1.6 Aspirin: 75~325 mg/day Main results: Oral anticoagulants were associated with lower risk of All stroke Ischemic stroke Systemic emboli Substantially but not significantly reduced by oral anticoagulants. All disa