Assessment of one-year risk of ischemic stroke versus major bleeding in patients with atrial fibrillation

BACKGROUND: Patients diagnosed with atrial fibrillation (AF) are at increased risk of stroke. Several guidelines to assess the risk of ischemic stroke and major bleeding in AF patients have been published. The CHA(2)DS(2)-VASc score has been adopted widely for predicting stroke within one year of the index AF diagnosis and is used to guide the prescription of anticoagulants. Anticoagulation therapy increases the risk of bleeding and scoring systems such as HAS-BLED assess the risk of major bleeding in anticoagulated patients. Despite these advances, no study has examined the risks of the two outcomes simultaneously. How patients’ fear of particular outcomes affects these risks also remains unknown. METHODS: We incorporated the risks of ischemic stroke and major bleeding within one year of the index AF admission as well as the fear of stroke and bleeding of each individual patient. The patients enrolled in this retrospective observational study were identified using hospital admission data from the Myocardial Infarction Data Acquisition System (MIDAS), a statewide database including all hospitalizations for cardiovascular disease in New Jersey. Probabilities of the outcomes (ischemic stroke, major bleeding, both, or neither within one year of the index AF admission) were estimated using multinomial regression with patient demographics and comorbidities (heart failure [HF], hypertension [HTN], diabetes mellitus [DM], anemia, chronic obstructive pulmonary disease [COPD], kidney disease [KD], prior stroke or transient ischemic attack [TIA]) as predictors. These estimates were used in a Deming regression to model the association of ischemic stroke and major bleeding in grouped patients. The assessment of the importance of each outcome was superimposed on the final model to arrive at a recommendation for anticoagulation therapy. RESULTS: The results of the Deming regression indicated a positive relationship between ischemic stroke and major bleeding (slope = 1.67, 95% confidence interval [CI] 1.37 to 1.97). Estimates of the risks of the two outcomes and the lines of best fit from Deming regression were determined. This model for risk assessment of stroke and major bleeding within one year of the index AF hospital admission combined objective data and subjective assessment of the relative fear of stroke versus bleeding by each hypothetical patient on 0–100 scale. Examples with the fears of stroke versus major bleeding being equal (50-50) and a higher fear of stroke (80–20) are presented. CONCLUSIONS: The new model for risk assessment of ischemic stroke and major bleeding within one year of the index AF hospital admission proposed in this work used objective, empirically driven measures, and subjective assessment of the outcomes’ importance for individual patients. Such models may assist physicians in their decision making regarding anticoagulation therapy.