Combination therapy of beta-blockers and digoxin is associated with increased risk of major adverse cardiovascular events and all-cause mortality in patients with atrial fibrillation: a report from the GLORIA-AF registry

The effect of digoxin and beta-blockers on cardiovascular outcomes and mortality remains unclear. The study aimed to determine differences in cardiovascular (CV) outcomes and death rates among patients with atrial fibrillation (AF) who were prescribed with beta-blockers, digoxin or combination therapy. Data from phase II/III of the prospective Global Registry on Long-Term Oral Anti-thrombotic Treatment in Patients with Atrial Fibrillation (GLORIA-AF) were analysed. The risk of major cardiovascular events (MACE) and death among patients with different prescriptions using COX proportional hazard regression was considered. Propensity score (PS) matching and weighting were further used to adjust for potential confounders of prescription use. A total of 14,201 patients [median age: 71.0 (IQR 64.0-77.0) years; 46.2% female] were recruited. After a median follow-up of 3.0 (IQR 2.4-3.1) years, 864 MACE, and 988 all-cause deaths were recorded. The incidence rate (IR) of MACE was 22.4 (95%CI 21.0-24.0) per 1000 person-years, while the IR of all-cause death was 25.4 (95%CI 23.8-27.0) per 1000 person-years. After multivariate adjustment with Cox regression, the risk of MACE (HR 1.35, 95% CI 1.09-1.68) and the risk of all-cause death (HR 1.28, 95%CI 1.04-1.57) were significantly higher in the combination therapy group, compared to the beta-blockers alone group. The risks of MACE and all-cause death remained significant in both PS matched and PS weighted cohort Among AF patients, combination therapy of beta-blockers and digoxin was associated with higher risks of MACE and all-cause death compared to beta-blockers alone.