The impact of patients' preferences on the treatment of atrial fibrillation: Observational study of patient based decision analysis

Abstract

Objective. To investigate the impact of patients' preferences for the treatment of atrial fibrillation, by using individualised decision analysis combining probability and utility assessments into a decision tree. Design. Observational study based on interviews with patients. Setting. Eight general practices in Avon. Participants. 260 randomly selected patients aged 70-85 years with atrial fibrillation. Main outcome measures. Patients' treatment preferences regarding anticoagulation treatment (warfarin) after individualised decision analysis; comparison of these preferences with treatment guidelines on the basis of comorbidity and absolute risk and compared with current prescription. Results. Of 195 eligible patients, 97 participated in decision making using decision analysis. Among these 97, the decision analysis indicated that 59 (61%; 95% confidence interval 50% to 71%) would prefer anticoagulation treatment - considerably fewer than those who would be recommended treatment according to guidelines. There was marked disagreement between the decision analysis and guideline recommendations (κ = 0.25 or less). Of 38 patients whose decision analysis indicated a preference for anticoagulation, 17 (45%) were being prescribed warfarin; on the other hand, 28 (47%) of 59 patients were not being prescribed warfarin although the results of their decision analysis suggested they wanted to be. Conclusions. In the context of shared decision making, individualised decision analysis is valuable in a sizeable proportion of elderly patients with atrial fibrillation. Taking account of patients' preferences would lead to fewer prescriptions for warfarin than under published guideline recommendations. Decision analysis as a shared decision making tool should be evaluated in a randomised controlled trial.