Comparing Patient Preferences for Antithrombotic Treatment During the Acute and Chronic Phases of Myocardial Infarction: A Discrete-Choice Experiment.

backgroundAntithrombotic drugs are used as preventive treatment in patients with a prior myocardial infarction (MI) in both the acute and chronic phases of the disease. To support patient-centered benefit-risk assessment, it is important to understand the influence of disease stage on patient preferences.

objectiveThe aim of this study was to examine patient preferences for antithrombotic treatments and whether they differ by MI disease phase.

methodsA discrete-choice experiment was used to elicit preferences of adults in the acute (≤ 365 days before enrolment) or chronic phase (> 365 days before enrolment) of MI for key ischemic events (risk of cardiovascular [CV] death, non-fatal MI, and non-fatal ischemic stroke) and bleeding events (risk of non-fatal intracranial hemorrhage and non-fatal other severe bleeding). Preference data were analyzed using the multinomial logit model. Trade-offs between attributes were calculated as the maximum acceptable increase in the risk of CV death for a decrease in the risk of the other outcomes. To assess the potential effect of sociodemographic and clinical characteristics on patient preferences, subgroups were introduced as interaction terms in logit models.

resultsThe evaluable population included 155 patients with MI in the acute phase of disease and 180 in the chronic phase. The overall population was 82% male, mean age was 64.2 ± 9.6 years, and 93% had not experienced bleeding events or key ischemic events other than MI. Patients valued reduction in the risk of non-fatal intracranial hemorrhage more than CV death (p < 0.01) and CV death more than non-fatal ischemic events (p < 0.01). Preferences were similar in the acute and chronic populations (p = 0.17). However, older patients valued reduction in risk of MI more than younger patients (p = 0.04), and patients with bleeding risk factors valued reduction in the risk of CV death (p = 0.01) and MI (p = 0.01) less than patients without bleeding risk factors. Also, patients who were at high risk of future ischemic events valued reduction of the risk of CV death less than those at low risk (p = 0.01).

conclusionPatient preferences for antithrombotic treatments were unaffected by disease stage but varied by bleeding risk and other factors. This heterogeneity in preferences is an important consideration because it can affect the benefit-risk balance and the acceptability of antithrombotic treatments to patients.