Digoxin Side Effects Increase Risk of Death for Dialysis Patients: Study

Use of the heart medication digoxin by patients undergoing dialysis treatment has been linked to an increased risk of death, according to recent research. 

A new retrospective cohort study on the side effects of digoxin in patients undergoing kidney dialysis was published online in the Journal of the American Society of Nephrology on June 24. The effect appears to be dose-related, with researchers finding higher rates of death among patients given larger doses.

Digoxin is used to treat congestive heart failure, abnormal heart rhythms, atrial flutter and atrial fibrillation. The medication is extremely dose-specific with a narrow therapeutic index. If too little of drug is prescribed it can be ineffective, and if too much is prescribed it can lead to a digoxin overdose, where the drug builds up in the system. This can result in a serious and potentially life-threatening condition known as digitalis toxicity.

U.S. researchers looked at more than 120,000 dialysis patients from more than 1,800 clinics in North America. They found that the risk of death increased by 28% for dialysis patients taking digoxin. That rate increased with larger doses and if the patients had lower levels of potassium.

Researchers estimate that about 400,000 Americans have end-stage kidney disease, which increases the risk of heart failure. About 4% of all dialysis patients were prescribed digoxin to combat the effects of heart failure during the study, doctors said.

“We were surprised to find that digoxin use increased death risk in dialysis patients, especially in patients on higher doses,” Dr. Kevin Chan, a researcher from Fresenius Medical Care North America in Waltham, Massachusetts, said in a press release. “Further research is needed to outline how and if digoxin can be safely prescribed in patients on hemodialysis.”

In April 2008, Actavis Totowa issued a digoxin recall for all lots of their version heart drug, which was marketed as Digitek, after it was discovered that some tablets may have been commercially released that were twice as thick as they were supposed to be. According to a December 2008 report released by the non-profit Center for Public Justice, the FDA received reports of at least 667 Digitek overdose deaths tied to the recalled pills between April 2008 and June 2008.

There are currently more than 200 Digitek lawsuits pending in the federal MDL, which all involve similar allegations that Actavis Totowa and their distributors sold over-sized Digitek pills, which caused users to suffer a variety of serious and potentially life-threatening injuries associated with receiving too much of the heart medication. The first trial is expected to begin in January 2011.