new biomarkers based on smoking-related phenotypes for smoking cessation outcomes of nicotine replacement therapy: a prospective study

Introduction: identifying a potent biomarker for smoking cessation can play a key role inpredicting prognosis and improving treatment outcomes. this study aimed to evaluate thecontribution of new biomarkers based on the levels of cotinine (cot) and carbon monoxide(co) to the short- and long-term quit rates of nicotine replacement therapies (nicotine patch[np] and nicotine lozenge [nl]).methods: in this prospective interventional study, 124 smokers under treatment with the 5a’smethod were selected from an outpatient smoking cessation center in district 18 of tehran city,iran. the study was conducted from april 2016 to december 2018. they were divided into np(n=56) and nl (n=61) intervention groups. the levels of cot and co were measured usingelisa and breath analysis at the beginning of the study. three markers were calculated: cot/co, cot to cigarette per day ratio (cot/cpd), and co/cpd. binary logistic regression modelsand generalized estimating equations models were analyzed by spss software, version 21 todetermine the chances of quitting smoking.results: of the np participants, 30.4% and 19.6% were abstinent after 2 and 6 months,respectively, while nl was found less effective with 19.7% for 2-month follow-up and 13.1%for 6-month follow-up. the 6-month success of quitting attempts was significantly different forthe np participants at the second half of cot/co (p=0.029). of the nl participants, co/cpdwould be a superior predictor for smoking cessation success (p>0.05).conclusion: the findings of this study suggested two markers of cot/co and co/cpd in thisorder for the optimum treatment outcomes of np and nl.