Few models had addressed the cumulative nature of risk factors where a combination of risk factors would confer a greater risk than either factor alone .
In patients at high risk of stroke , anticoagulation is cost effective , but not for those with a low risk of stroke .
The risk of stroke in atrial fibrillation ( AF ) needs to be assessed in each patient to determine the clinical and cost-effectiveness of thromboprophylaxis , with the aim of appropriate use of antithrombotic therapy .
To achieve this , stroke risk factors in AF population s need to be identified and stroke risk stratification models have been devised on the basis of these risk factors .
In this article , we firstly provide a systematic review of studies examining the attributable stroke risk of various clinical , demographic and echocardiographic patient characteristics in AF population s. Secondly , we performed a systematic review of published stroke risk stratification models , in terms of the results of the review of stroke risk factors and their ability to accurately discriminate between different levels of stroke risk .
Cost-effectiveness of warfarin and aspirin for prophylaxis of stroke in patients with nonvalvular atrial fibrillation.
OBJECTIVE To examine the cost-effectiveness of prescribing warfarin sodium in patients who have nonvalvular atrial fibrillation ( NVAF ) with or without additional stroke risk factors ( a prior stroke or transient ischemic attack , diabetes , hypertension , or heart disease ) . DESIGN Decision and cost-effectiveness analyses . The probabilities for stroke , hemorrhage , and death were obtained from published r and omized controlled trials . The quality -of-life estimates were obtained by interviewing 74 patients with atrial fibrillation .  Costs were estimated from literature review , phone survey , and Medicare reimbursement . PATIENTS In the base case , the patients were 65 years of age and good c and i date s for warfarin therapy . INTERVENTIONS Treatment with warfarin , aspirin , or no therapy in the decision analytic model . MAIN OUTCOME MEASURES Quality -adjusted survival and marginal cost-effectiveness of warfarin  as compared with  aspirin  or no therapy . RESULTS For patients with NVAF and additional risk factors for stroke , warfarin therapy led to a greater quality -adjusted survival and to cost savings . For patients with NVAF and one additional risk factor , warfarin therapy cost $ 8000 per quality -adjusted life-year saved . For 65-year-old patients with NVAF alone , warfarin cost about $ 370,000 per quality -adjusted life-year saved , as compared with aspirin therapy . However , for 75-year-old patients with NVAF alone , prescribing warfarin cost $ 110,000 per quality -adjusted life-year saved . For patients who were not prescribed warfarin , aspirin was preferred to no therapy on the basis of both quality -adjusted survival and cost in all patients , regardless of the number of risk factors present . CONCLUSIONS Treatment with warfarin is cost-effective in patients with NVAF and one or more additional risk factors for stroke . In 65-year-old patients with NVAF but no other risk factors for stroke , prescribing warfarin instead of aspirin would affect quality -adjusted survival minimally but increase costs significantly
Few models had addressed the cumulative nature of risk factors where a combination of risk factors would confer a greater risk than either factor alone .
In patients at high risk of stroke , anticoagulation is cost effective , but not for those with a low risk of stroke .
The risk of stroke in atrial fibrillation ( AF ) needs to be assessed in each patient to determine the clinical and cost-effectiveness of thromboprophylaxis , with the aim of appropriate use of antithrombotic therapy .
To achieve this , stroke risk factors in AF population s need to be identified and stroke risk stratification models have been devised on the basis of these risk factors .
In this article , we firstly provide a systematic review of studies examining the attributable stroke risk of various clinical , demographic and echocardiographic patient characteristics in AF population s. Secondly , we performed a systematic review of published stroke risk stratification models , in terms of the results of the review of stroke risk factors and their ability to accurately discriminate between different levels of stroke risk .