Study: Arrhythmia Drug Amiodarone May Increase Cancer Risk
Drug can accumulate in soft tissues after long-term use (Apr. 8)
One of the most widely used medications to treat arrhythmias may increase the risk of developing cancer, especially in men and people exposed to high amounts of the drug. That is the conclusion of a new retrospective study published online in Cancer, a journal of the American Cancer Society. The study’s results indicate that a potential link between amiodarone and cancer warrants further investigation.
Amiodarone was approved in 1985 for the treatment of arrhythmias. Because the drug is fat-soluble and degrades very slowly, large amounts can accumulate in soft tissues after a long-term prescription. Previous studies have shown that amiodarone may increase the risk of certain cancers, but no large-scale study has looked at the issue.
To investigate, Vincent Yi-Fong Su, MD, and his colleagues evaluated 6,418 individuals in Taiwan who were taking the drug and followed them for an average of 2.57 years. A total of 280 participants developed cancer.
Patients who were male or who received high cumulative daily doses of amiodarone within the first year had an increased risk of developing cancer. Those with both risk factors were 46% more likely to develop cancer than were those with neither factor. After taking age, sex, and illnesses into account, the investigators found that individuals treated with a high amount of amiodarone had nearly twice the risk of developing cancer as did those taking a low amount of the drug.
“We suggest that cancer events should be routinely reported in future amiodarone trials, and further observational research is necessary,” Su said. “Also, when prescribing amiodarone, doctors need to keep in mind that this medication may increase cancer risk.”