'Metabolizer Test' Might Someday Take Guesswork Out of Quitting Smoking

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MONDAY, Jan. 12, 2015 (HealthDay News) -- Quitting smoking is notoriously tough, and some smokers may try different approaches for years before they succeed, if ever.

But new research suggests that someday, a simple test might point smokers toward the quitting strategy that's best for them.

It's been long theorized that some smokers are genetically predisposed to process and rid the body of nicotine more quickly than others. And now a new study suggests that slower metabolizers seeking to kick the habit will probably have a better treatment experience with the aid of a nicotine patch than the quit-smoking drug varenicline (Chantix).

The finding is based on the tracking of more than 1,200 smokers undergoing smoking-cessation treatment. Blood tests indicated that more than 660 were relatively slow nicotine metabolizers, while the rest were normal nicotine metabolizers.

Over an 11-week trial, participants were prescribed a nicotine patch, Chantix, or a non-medicinal "placebo."

As reported online Jan. 11 in The Lancet Respiratory Medicine, normal metabolizers fared better using the drug compared with the nicotine patch.

Specifically, 40 percent of normal metabolizers who were given the drug option were still not smoking at the end of their treatment, the study found. This compared with just 22 percent who had been given a nicotine patch.

Among the slow-metabolizing group, both treatments worked equally well at helping smokers quit, the researchers noted. However, compared with those treated with the nicotine patch, slow metabolizers treated with Chantix experienced more side effects.

This led the team to conclude that slow metabolizers would fare better -- and likely remain cigarette-free -- when using the patch.

The study was led by Caryn Lerman, a professor of psychiatry and director of the Center for Interdisciplinary Research on Nicotine Addiction at the University of Pennsylvania School of Medicine. She believes that the findings show that not all smokers are alike, and measuring each smokers' "nicotine metabolite ratio" might someday be a useful tool "to guide treatment choices."

"This is a much-needed, genetically informed [measurement tool] that could be translated into clinical practice," Lerman said in a university news release. "Matching a treatment choice based on the rate at which smokers metabolize nicotine could be a viable strategy to help guide choices for smokers and ultimately improve quit rates."

Anti-smoking experts agreed.

"If clinicians can predict which cessation medications will work better for a particular smoker -- the slow nicotine metabolizer or the normal metabolizer -- the frustrating process of trial and error may be reduced or eliminated," said Patricia Folan, director of the Center for Tobacco Control at North Shore-LIJ Health System in Great Neck, N.Y.

"Quitting is challenging for most tobacco users," Folan said. "Guiding them to appropriate treatment more quickly and efficiently will provide a more satisfying experience, with possibly less relapse."

Dr. Len Horovitz is a pulmonary specialist at Lenox Hill Hospital in New York City. He said that, in the future, "a specific therapy may be tailored to the patient based on how the patient metabolizes nicotine. This eliminates the 'one-size-fits-all' approach."

More information

For more on quitting smoking, head to the U.S. Centers for Disease Control and Prevention.