By Antonio Bradley
Controversy continues over the widespread use of digoxin in atrial fibrillation, after a large study linked it to premature death.
The four-year study of 4000 AF patients at high stroke risk found those treated with digoxin were 41% more likely to die from any cause than those who didn’t take the drug.
This effect persisted regardless of patients’ comorbidities, including heart failure, and was common to both males and females.
It is the latest in a string of conflicting findings on digoxin: some studies suggest the drug itself is responsible for increased mortality, whereas others suggest mortality simply appears higher because digoxin is prescribed to sicker patients.
“Digoxin has survived as a mainstay of therapy for AF and congestive heart failure for decades despite controversies about its safety,” researchers wrote Tuesday in the European Heart Journal (online).
“These findings call into question the widespread use of digoxin in patients with AF.”
Sydney cardiologist Dr Jason Kaplan said digoxin was widely used in Australia for second and third-line treatment of AF, but not as first-line due to its relative ineffectiveness in sedentary patients.
However, he played down the study’s findings, noting that mortality was an incidental finding. The trial’s main aim had been to compare rate vs rhythm control in the treatment of AF.
“I think in real life, patients who get digoxin are a sicker group,” said Dr Kaplan.
“They may have increased problems with digoxin because of comorbidities such as renal dysfunction.”
It was worthwhile monitoring digoxin levels more frequently in older patients, those taking multiple medications and those with renal dysfunction, and being vigilant for drug interactions and excretion problems, he said.
The researchers assessed mortality rates in people who took digoxin during the study, or within six months prior.
Patients who took digoxin were 35% more likely to die from cardiovascular causes, and 61% more likely to die from arrhythmic causes, than those who didn’t.
Sixty hundred and sixty six patients died during the study.