Atrial fibrillation (AF) is typically a supraventricular tachyarrhythmia which is known for having an uncoordinated atrial activation resulting in worsening of atrial mechanical function. (1) AF is very common and presents around one-third of hospital admissions due to cardiac rhythm disturbances. There has been a substantial increase in hospital admission for AF which can be the result of an aging of the population and an increase in prevalence chronic heart disease.(2–4)
Nonvalvular AF is associated with increased risk of ischemic stroke at an average annual rate of 5% and a 2 to 7 folds increase in risk compared to normal people.(5,6) One of six ischemic strokes is associated with AF which is mostly due to cardiogenic embolism. These patients …show more content…
1.2 Objective
The objective of this study is to develop and apply an individualized risk-benefit model that quantifies the impact of use of Warfarin for stroke prevention in patients with nonalveolar AF in a large population of UK users. The combined RRs from clinical trials and absolute risks from epidemiologic studies will be used to estimate the attributable risks of warfarin use in a representative population of drug users.
In this study we are going to estimate the attributable risks for both the beneficial and harmful effects of warfarin in nonalveolar AF. Attributable risk, is the part of the observed risk that occurs over a particular time period due to exposure. A benefit-risk simulation is going to be employed to estimate the net impact of use of Warfarin in this patient population. 2. Methods
2.1 Data …show more content…
The meta-analysis by Hart et al estimated that the risk of stroke is decreased by 60% in Warfarin users as compared to non-users and that an absolute increases in major extracranial hemorrhage of 0.3% is observed annually.(10)
Weighting of harm and benefit
The overall estimate of the harm–benefit ratio of Warfarin will be calculated by weighting the different outcomes each of the by 1-year post event mortality, a method that has been previously described by Wright and Weinstein and used by van Staa et al in their individualized benefit-risk model. (13,14) Stroke will be considered the reference because of its higher mortality and major extracranial bleeding will be compared to it to find the fraction of a stroke major bleeding is equal
Nonvalvular AF is associated with increased risk of ischemic stroke at an average annual rate of 5% and a 2 to 7 folds increase in risk compared to normal people.(5,6) One of six ischemic strokes is associated with AF which is mostly due to cardiogenic embolism. These patients …show more content…
1.2 Objective
The objective of this study is to develop and apply an individualized risk-benefit model that quantifies the impact of use of Warfarin for stroke prevention in patients with nonalveolar AF in a large population of UK users. The combined RRs from clinical trials and absolute risks from epidemiologic studies will be used to estimate the attributable risks of warfarin use in a representative population of drug users.
In this study we are going to estimate the attributable risks for both the beneficial and harmful effects of warfarin in nonalveolar AF. Attributable risk, is the part of the observed risk that occurs over a particular time period due to exposure. A benefit-risk simulation is going to be employed to estimate the net impact of use of Warfarin in this patient population. 2. Methods
2.1 Data …show more content…
The meta-analysis by Hart et al estimated that the risk of stroke is decreased by 60% in Warfarin users as compared to non-users and that an absolute increases in major extracranial hemorrhage of 0.3% is observed annually.(10)
Weighting of harm and benefit
The overall estimate of the harm–benefit ratio of Warfarin will be calculated by weighting the different outcomes each of the by 1-year post event mortality, a method that has been previously described by Wright and Weinstein and used by van Staa et al in their individualized benefit-risk model. (13,14) Stroke will be considered the reference because of its higher mortality and major extracranial bleeding will be compared to it to find the fraction of a stroke major bleeding is equal