TitleNicotine Metabolism in Young Adult Daily Menthol and Non-Menthol Smokers.
Publication TypeJournal Article
Year of Publication2015
AuthorsFagan, P, Pokhrel, P, Herzog, TA, Pagano, I, Franke, A, Clanton, MS, Alexander, LA, Trinidad, DR, Sakuma, K-L, Johnson, CA, Moolchan, ET
JournalNicotine & tobacco research : official journal of the Society for Research on Nicotine and Tobacco
Date Published2015 May 19

INTRODUCTION: Menthol cigarette smoking may increase the risk for tobacco smoke exposure and inhibit nicotine metabolism in the liver. Nicotine metabolism is primarily mediated by the enzyme CYP2A6 and the nicotine metabolite ratio (NMR= trans 3'hydroxycotinine/cotinine) is a phenotypic proxy for CYP2A6 activity. No studies have examined differences in this biomarker among young adult daily menthol and non-menthol smokers. This study compares biomarkers of tobacco smoke exposure among young adult daily menthol and non-menthol smokers. METHODS: Saliva cotinine and carbon monoxide were measured in a multi-ethnic sample of daily smokers aged 18-35 (n=186). Nicotine, cotinine, the cotinine/cigarette per day ratio, trans 3' hydroxycotinine, the NMR, and expired carbon monoxide were compared. RESULTS: The geometric means for nicotine, cotinine, and the cotinine/cigarette per day ratio did not significantly differ between menthol and non-menthol smokers. The NMR was significantly lower among menthol compared to non-menthol smokers after adjusting for race/ethnicity, gender, body mass index, and cigarette smoked per day (0.19 versus 0.24, p=.03). White menthol smokers had a significantly higher cotinine/cigarettes per day ratio than White non-menthol smokers in the adjusted model. White menthol smokers had a lower NMR in the unadjusted model (.24 versus .31, p=.05) and the differences remained marginally significant in the adjusted model (0.28 versus 0.34, p=.06). We did not observe these differences in Native Hawaiians and Filipinos. CONCLUSIONS: Young adult daily menthol smokers have slower rates of nicotine metabolism than non-menthol smokers. Studies are needed to determine the utility of this biomarker for smoking cessation treatment assignments.