The heartbeat of America

Recently, I told you about two common drugs that can cause fatal cardiac arrhythmias. An arrhythmia is the medical term for an abnormal heartbeat. And now, it turns out that a drug used to treat arrhythmias causes cancer.

Earlier this month, researchers published a report linking the drug amiodarone with an increased risk for cancer in men. This drug is sold as Nexterone in the U.S. Cardiologists widely prescribe it to treat arrhythmias and atrial fibrillation.

For the study, researchers used the Taiwan National Health Insurance Research database to identify more than 6,000 patients treated with amiodarone. The researchers observed the patients from 1997 to 2008.

During the study, 280 cancers developed. In fact, all patients who took amiodarone had overall increases in risk for cancer compared to the general population.

More specifically, men 20 to 59 years and men 80 years and older had significantly greater risks of developing cancer. And the incidence of cancer rose in the first year of beginning therapy with this drug.

In addition, the risk appeared to be dose dependent. So, the higher the dose, the greater risk of cancer. This helps pinpoint the drug as the cause of cancer. And not just a statistical association.

Researchers divided the subjects into three groups. They found that subjects taking the highest doses of amiodarone had an adjusted cancer risk of 1.98. This is nearly two times greater than the group taking the lowest dose. The group that took an intermediate dose had a 1.70 times higher risk. Again, that’s compared to the group taking the lowest dose.

Amiodarone accumulates in fat tissues. It also breaks down very slowly in the body. Experts think this is why men who take higher doses of the drug run a greater cancer risk.

The lead Taiwanese researcher told Medscape Today News, “We suggest that cancer events be routinely reported in future amiodarone trials, and further observational research is necessary.”

“When prescribing amiodarone, doctors need to keep in mind that this medication may increase cancer risk,” he also said.

Some experts don’t seem worried.

Take James Marshall, Ph.D., for example. He’s the senior vice president for cancer prevention and population sciences and chair of the Department of Cancer Prevention and Population Sciences at the Roswell Park Cancer Institute in Buffalo, New York.

He told Medscape, “While we need to take note of these data, we should take them with a grain of salt.”

Go ahead Dr. Marshall. Keep your head buried in the sand.

The U.S. Food and Drug Administration wrapped up post-marketing surveillance for this drug. And it found an excess of cases of lung masses, thyroid cancer, and skin cancer.

But even these findings are not changing medical practice.

Dr. Marshall said “I don’t think cardiologists are going to change treatment based on this one study alone. We need to be careful about coming to conclusions until we see some confirmation of this in other studies.”

So if your cardiologist does not reconsider your treatment based on this solid study showing a clear, dose-response effect, maybe you should change your cardiologist.

Here we have another new heart drug that increases your cancer risk. Statin drugs–supposedly doled out to prevent heart disease–lower cholesterol. But this benefit is questionable, at best. We have known for decades that low cholesterol is associated with an increased risk of certain cancers. And the World Health Organization recently reaffirmed this finding by looking at populations worldwide.

So, maybe it’s time to ask your cardiologist this…

Is the real goal of cardiac therapy to make sure you die of cancer before heart disease can get you?  That way, heart disease may drop to the number two killer and make cancer number one. When you’re number two, you have to try harder.


1. 8 APR 2013 DOI: 10.1002/cncr.27881