Despite decline in use, rates of digoxin toxicity still high

Although clinicians use digoxin less frequently as newer, safer agents start taking its place, toxicity has not decreased, which suggests the need for better management and monitoring of the drug, according to a study published online Dec. 3 in Circulation: Heart Failure.

“Understanding the current epidemiology of digoxin toxicity could provide additional context for renewed considerations of digoxin use in heart failure,” wrote the authors, led by Isaac See, MD, of the Centers for Disease Control and Prevention.

The investigators used data from the National Electronic Injury Surveillance System-Cooperative Adverse Drug Event Surveillance (NEISS-CADES) project, which consisted of information from 63 hospitals. For this study, however, the researchers used data from the 58 nonpediatric hospitals and identified conditions that clinicians said were due to medication use or were adverse effects caused by a drug.

Between 2005 and 2010, there were 441 cases of digoxin-associated adverse events among patients 40 and older reported to NEISS-CADES. Based on this number of patients, there were more than 5,100 visits to an emergency department (ED) per year and more than 75 percent of them were hospitalized. More than 95 percent of them had a high serum digoxin level (2.0 ng/mL). Visits to the ED were more than doubled for 85-year-olds compared to younger patients. Women also visited the ED for digoxin-related events twice as often as men.

Of all the hospitalizations for all adverse drug events, 1 percent occurred due to digoxin toxicity. The rates of ED visits and hospitalizations associated with digoxin were about the same between 2005 and 2010.

Although they acknowledged that using NEISS-CADES limits analysis to events in only certain settings, the authors called for a closer look into digoxin protocols in certain populations.

“Careful patient selection for digoxin therapy, proper initial dosing, and heightened surveillance for high-risk patients, such as females and older adults, might mitigate the burden of ED visits and hospitalizations for digoxin toxicity,” they wrote.

Cardiovascular Business recently delved into the debate over digoxin as a treatment in patients with heart failure. Read the article here.