Outcomes of a contemporary sample of patients with atrial fibrillation taking digoxin: results from the AFBAR study

Introduction and objectives: We aimed to assess and compare the effect of digoxin on clinical outcomes in patients with atrial fibrillation vs those under beta-blockers or none of these drugs.

Methods: AFBAR is a prospective registry study carried out by a team of primary care physicians (n=777 patients). Primary endpoints were survival, survival free of admission due to any cause, and survival free of admission due to cardiovascular causes. The mean follow up was 2.9 years. Four groups were analyzed: patients receiving digoxin, beta-blockers, or digoxin plus beta-blockers, and patients receiving none of these drugs.

Results: Overall, 212 patients (27.28%) received digoxin as the only heart control strategy, 184 received beta-blockers (23.68%), 58 (7.46%) were administered both, and 323 (41.57%) received none of these drugs. Digoxin was not associated with all-cause mortality (estimated hazard ratio=1.42; 95% confidence interval, 0.77-2.60; P=.2), admission due to any cause (estimated hazard ratio=1.03; 95% confidence interval, 0.710-1.498; P=.8), or admission due to cardiovascular causes (estimated hazard ratio=1.193; 95% confidence interval, 0.725-1.965; P=.4). No association was found between digoxin use and all-cause mortality, admission due to any cause, or admission due to cardiovascular causes in patients without heart failure. There was no interaction between digoxin use and sex in all-cause mortality or in survival free of admission due to any cause. However, an association was found between sex and admission due to cardiovascular causes.

Conclusions: Digoxin was not associated with increased all-cause mortality, survival free of admission due to any cause, or admission due to cardiovascular causes, regardless of underlying heart failure.