[The impact of digoxin on the long-term outcomes in patients with coronary artery disease and atrial fibrillation]

Abstract

Objective: To investigate the long-term safety of digoxin in patients with coronary artery disease (CAD) and atrial fibrillation (AF). Methods: This was a prospective study, in which 25 512 AF patients were enrolled from China Atrial Fibrillation Registry Study. After exclusion of patients receiving ablation therapy at the enrollment, 1 810 CAD patients [age: (71.5±9.3)years] with AF were included. The subjects were grouped into the digoxin group and non-digoxin group, and were followed up for a period of 80 months. Long-term outcomes were compared between the groups and an adjusted Cox regression analysis was applied to evaluate the risk of digoxin on the long-term outcomes. The primary endpoint was all-cause mortality. Results: The patients were followed up for a median period of 3.05 years. After multivariable adjustment, the Cox regression analysis showed that digoxin significantly increased the risk of all-cause mortality (HR=1.28, 95%CI 1.01-1.61, P=0.038), cardiovascular mortality (HR=1.48,95%CI 1.10-2.00,P=0.010), cardiovascular hospitalization (HR=1.67,95%CI 1.35-2.07,P=0.008) and the composite endpoints (HR=2.02,95%CI 1.71-2.38,P<0.001). In the subgroup of patients with heart failure (HF), digoxin was not associated with the risk of all-cause mortality, but was still associated with the increased risk of cardiovascular mortality (HR=1.44,95%CI 1.05-1.98,P=0.025), cardiovascular hospitalization (HR=1.44,95%CI 1.09-1.90,P=0.010) and the composite endpoints (HR=1.37, 95%CI 1.01-1.70, P=0.004). However, in the subgroup of patients without HF, digoxin was only associated with all-cause mortality (HR=2.56,95%CI 1.44-4.54,P=0.001). Conclusion: Digoxin significantly increased the risk of all-cause mortality in CAD patients with AF, especially in patients without HF.