April 15, 2015
The antiarrhythmic drug (AAD) amiodarone had the lowest risk of hospitalizations among younger atrial fibrillation (AF) patients without structural heart disease, according to a recent study.
The researchers identified 8,562 patients with a median age of 56 years to see if they had been prescribed ADDs within two weeks of the initial AF episode. According to the study, 2,984 patients received Class 1C ADDs, 2,905 took amiodarone, 2,065 were prescribed sotalol, and 608 were on dronedarone. The adjusted risk of AF and cardiovascular hospitalization was greatest among patients who received dronedarone and lowest in those who received amiodarone.
There was no significant difference in AF, cardiovascular, or all-cause hospitalizations between Class 1C drugs and sotalol, but amiodarone reduced the hospitalization rates compared with all the drugs, according to Dr. Nancy Allen LaPointe, study lead author and an associate professor of medicine at Duke University School of Medicine in Durham, North Carolina.
Most previous studies typically focused on AF patients who have cardiovascular disease (CVD) and heart failure (HF), according to Dr. Allen LaPointe.
“We were interested in younger patients who did not have those comorbid conditions, because we had in prior studies identified that there are a fair number of people who fall into that category,” she said. “Current clinical practice guidelines focus more on where there is evidence — older folks who have concomitant heart disease.”
Amiodarone is often considered the most effective AAD for reducing recurrences of AF, although its efficacy in this patient population is largely unknown, said Dr. Allen LaPointe. “Unfortunately,” she added, “it’s also known to have a large number of side effects, some of which may be severe enough to require discontinuation or hospitalizations for treatment.”
She said the current findings provided a better understanding of the overall impact of ADDs, but also highlighted a need for additional research in this subset of AF patients. “We have a whole population of patients that we know very little about,” she explained. “Questions persist about trying to select the best treatment, and it would be very helpful to identify the safest and most effective option.”
Amiodarone is not approved by the U.S. Food and Drug Administration for treating AF, pointed out Dr. Allen LaPointe, but she said multiple studies have shown that it's one of the most commonly prescribed antiarrhythmics for treating AF patients.
“Starting the therapy in younger patients, especially those without heart disease, is a little concerning because you’d anticipate them being on the drug long-term,” she commented. “They could develop adverse outcomes, and now you’ve got AF patients with other complications.”
She suggested pharmacists look carefully at the ADDs selected for younger AF patients without other heart issues. “Is amiodarone justified because of other clinical factors, or would they be better served with another treatment that would avoid long-term downstream adverse effects?”
The study was published online in the journal Circulation: Cardiovascular Quality and Outcomes.
1. LaPointe NM, Dai D, Thomas L, Piccini JP, Peterson ED, Al-Khatib SM. Comparisons of hospitalization rates among younger atrial fibrillation patients receiving different antiarrhythmic drugs. Circ Cardiovasc Qual Outcomes. 2015 Mar 31. [Epub ahead of print]