Patient values and preferences when choosing anticoagulants.

backgroundNew oral anticoagulants have similar efficacy and lower bleeding rates compared with warfarin. However, in case of bleeding there is no specific antidote to reverse their effects. We evaluated the preferences and values of anticoagulants of patients at risk of atrial fibrillation and those who have already made a decision regarding anticoagulation.

methodsWe conducted a cross-sectional study of Veterans in the primary care clinics and the international normalized ratio (INR) laboratory. We developed an instrument with patient and physician input to measure patient values and preferences. The survey contained a hypothetical scenario of the risk of atrial fibrillation and the attributes of each anticoagulant. After the scenario, we asked participants to choose the option that best fits their preferences. The options were: 1) has better efficacy at reducing risk of stroke; 2) has been in the market for a long period of time; 3) has an antidote to reverse the rare case of bleeding; 4) has better quality of life profile with no required frequent laboratory tests; or 5) I want to follow physician recommendations. We stratified our results by those patients who are currently exposed to anticoagulants and those who are not exposed but are at risk of atrial fibrillation.

resultsWe approached 173 Veterans and completed 137 surveys (79% response rate). Ninety subjects were not exposed to anticoagulants, 46 reported being on warfarin, and one reported being on dabigatran at the time of the survey. Ninety-eight percent of subjects stated they would like to participate in the decision-making process of selecting an anticoagulant. Thirty-six percent of those exposed and 37% of those unexposed to anticoagulants reported that they would select a medication that has an antidote even if the risk of bleeding was very small. Twenty-three percent of the unexposed and 22% of the exposed groups reported that they would prefer the medication that gives the best quality of life.

conclusionOur study found that patients who may be exposed to an anticoagulation decision prefer to actively participate in the decision-making process, and have individual values for making a decision that cannot be predicted or assumed by anyone in the health care system.