Digoxin associated with higher mortality in afib patients

Digoxin was associated with a significant increase in all-cause mortality in patients with atrial fibrillation, regardless of gender and whether they had had heart failure, a study found.

To determine the relationship between digoxin and mortality in patients with atrial fibrillation, researchers assessed patients enrolled in the AF Follow-Up Investigation of Rhythm Management (AFFIRM) trial. Analyses were conducted in all patients and in subsets according to the presence or absence of heart failure, as defined by a history of heart failure and/or an ejection fraction less than 40%.

Results appeared online Nov. 27 in the European Heart Journal.

Digoxin was associated with an increase in all-cause mortality (estimated hazard ratio [EHR], 1.41; 95% CI, 1.19 to 1.67; P<0.001), cardiovascular mortality (EHR, 1.35; 95% CI, 1.06 to 1.71; P=0.016), and arrhythmic mortality (EHR, 1.61; 95% CI, 1.12 to 2.30; P=0.009). The all-cause mortality was increased with digoxin in patients without or with heart failure (EHR, 1.37; 95% CI, 1.05 to 1.79; P=0.019 and EHR, 1.41; 95% CI, 1.09 to 1.84; P=0.010, respectively). There was no significant interaction between digoxin and gender for all-cause (P=0.70) or cardiovascular (P=0.95) mortality.

These findings call into question the widespread use of digoxin in patients with atrial fibrillation, researchers wrote. Recent studies put its use at between 35% and 70% of these patients, despite limited safety data and controversy over its use.

“Digoxin may seem appealing for patients with AF [atrial fibrillation] and HF [heart failure], in whom positive inotropic effects and improved neurohormonal responses are desired,” the researchers wrote. “Digoxin may also be beneficial during SR [sinus rhythm] by reducing the heart rate as suggested in an analysis of the Dig trial. However, in our analysis, digoxin was associated with a 41% increase in mortality for patients with HF.”