Pérez-Martín, HipólitoLidón-Moyano, CristinaGonzález-Marrón, AdriánFu, MarcelaPérez Ortuño, Raúl, 1976-Ballbè, MontseMartín-Sánchez, Juan CarlosPascual Esteban, José A.Fernández, EsteveMartínez-Sánchez, Jose M.2023-03-212023-03-212023Pérez-Martín H, Lidón-Moyano C, González-Marrón A, Fu M, Pérez-Ortuño R, Ballbè M, et al. Variation in nicotine metabolization according to biological factors and type of nicotine consumer. Healthcare. 2023 Jan 2;11(2):179. DOI: 10.3390/healthcare110201792227-9032http://hdl.handle.net/10230/56299This study aims to describe the nicotine metabolite ratio among tobacco smokers and electronic cigarette (e-cigarette) users and nonusers. We analyzed pooled data from a longitudinal and a cross-sectional study of the adult population from the city of Barcelona. The final sample included information on 166 smokers, 164 e-cigarettes users with nicotine, 41 e-cigarette users without nicotine, 95 dual users (users of both products), and 508 nonusers. We used log-linear models to control for the potential confounding effect of the daily number of cigarettes smoked. Salivary nicotine metabolic rate assessment included the rate of nicotine metabolism (cotinine/nicotine) and the nicotine metabolite ratio (trans-3′-hydroxycotinine/cotinine). Exclusive users of e-cigarette without nicotine have the lowest rate of nicotine metabolism (Geometric mean: 0.08, p-values < 0.001) while cigarette smokers have the highest (Geometric mean: 2.08, p-values < 0.001). Nonusers have lower nicotine metabolic rate than cigarette smokers (Geometric means: 0.23 vs. 0.18, p-value < 0.05). Younger individuals (18–44 years) have a higher rate of nicotine metabolism than older individuals (45–64 years and 65–89) (Geometric means: 0.53 vs. 0.42 and 0.31, respectively, p-values < 0.01) and individuals with lower body mass index (21–25 kg/m2) have a higher rate of nicotine metabolism than the rest (26–30 kg/m2 and 31–60 kg/m2) (Geometric means: 0.52 vs. 0.35 and 0.36, respectively-values < 0.01). Nicotine metabolic rates are useful biomarkers when reporting smoking status and biological differences between individuals.application/pdfeng© 2023 by the authors. Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (https://creativecommons.org/licenses/by/4.0/).Variation in nicotine metabolization according to biological factors and type of nicotine consumerinfo:eu-repo/semantics/articlehttp://dx.doi.org/10.3390/healthcare11020179BiomarkerCotinineElectronic cigaretteNicotineNicotine metabolismSmokinginfo:eu-repo/semantics/openAccess