MONTREAL – A simple saliva test to assess a smoker's degree of nicotine dependence could become the first step of a smoking cessation treatment, a study has shown.
Light or heavy nicotine dependence can predict a person's success in quitting or risk of relapse, Caryn Lerman, Ph.D., said at the annual meeting of the Society of Behavioral Medicine. Clinicians could use this information to guide treatment choices for their patients.
“We could decide whether someone needs smoking cessation counseling only, or whether they would do better with a patch, or if they need a medication such as bupropion or varenicline,” said Dr. Lerman of the Transdisciplinary Tobacco Use Research Center at the University of Pennsylvania, Philadelphia.
The saliva test measures the ratio of two nicotine metabolites, 3′-hydroxycotinine and cotinine, to determine a person's rate of nicotine clearance or metabolism, Dr. Lerman said.
A new study by her group has validated that smokers with the slowest nicotine metabolism are about twice as likely to quit as are smokers with faster nicotine metabolism (Pharmacol. Biochem. Behav. 2009;92:6-11). The study enrolled 568 smokers who were given counseling and 8 weeks of a 21-mg nicotine patch. The saliva test measured the metabolite ratio pretreatment to distinguish fast from slow nicotine metabolizers. Eight weeks after the quit date, fast metabolizers were approximately 50% less likely to be abstinent, compared with slow metabolizers (28% vs. 42%).
The findings support the value of the saliva test as a biomarker to predict success with transdermal nicotine for smoking cessation, the authors concluded. “We are developing a treatment algorithm which suggests that slow metabolizers may need nothing more than counseling or nicotine patch, but fast metabolizers are candidates for more nonnicotine medications which may be more costly and have more side effects than the patch,” they wrote (Clin. Pharmacol. Ther. 2008;84:320-5).