There's good news for people trying to quit smoking: Aids such as nicotine gums and patches or smoking cessation drugs such as Chantix won't harm the heart.
The new findings may ease concerns that some products that help people "butt out" may pose a threat to heart health, the researchers noted.
One expert said patients sometimes wonder about the safety of certain products.
"Patients are often concerned that nicotine replacement therapies, such as the nicotine gum or patch, will harm them," said Dr. Jonathan Whiteson, a smoking cessation specialist at NYU Langone Medical Center in New York City. "However in most situations, patients are getting more nicotine from their smoking habit than from nicotine replacement when not smoking."
The results "should give reassurance to smokers trying to quit with nicotine replacement therapy, as well as health care practitioners prescribing them, that there is no significant or long-term detrimental effect from their use," Whiteson said.
The new study was led by Edward Mills, an associate professor of medicine at Stanford University and Canada Research Chair at the University of Ottawa. His team analyzed 63 studies, comprising more than 30,500 people, to assess the heart-related effects of nicotine replacement gums and patches, the nicotine addiction treatment varenicline (Chantix), and the antidepressant buproprion (Wellbutrin).
The study found that nicotine replacement therapies temporarily increased the chances of a rapid or abnormal heartbeat, but this most often occurred when people were still smoking while using them. There was no increased risk of serious heart events with these treatments alone, according to the study published Dec. 9 in the journal Circulation.
"These more minor risks are well known to clinicians and usually pass with time. They occur most often when people are taking nicotine replacement therapy and smoking at the same time, which is a bad idea," Mills said in a journal news release.
Whiteson agreed. "Patients are always counseled not to smoke and use nicotine replacement at the same time, as this can lead to an increased risk of side effects from nicotine overdose," he said. "Nicotine replacement protocols are designed to start after the last cigarette is smoked to avoid this."
The study also found no evidence that the use of Chantix boosted the risk of heart attack, stroke or heart-related death, and buproprion actually protected against these serious heart events.
The bottom line, according to Mills, is that, "undoubtedly, the benefits of quitting smoking outweigh any potential risks from smoking cessation therapies."
He did note, however, that most of the patients in the analysis were relatively healthy, so the findings may not be true for everyone.
"It's possible that the risk factors might be different in people with multiple diseases," Mills said. "Patients should discuss with their healthcare provider any potential risk factors that they may have developed from their smoking history. For patients who have chronic lung disease or other associated cardiovascular risks, clinicians should determine which smoking cessation aid to use by their risk profiles."
One heart specialist weighed in on the issue, as well. Dr. Evelina Grayver, director of the coronary care unit at North Shore University Hospital in Manhasset, N.Y., said that "the overall benefits of decreasing heart disease by using [drugs] to aid with smoking cessation significantly outweighs the potential risk of these therapies."