The Association Of High Nicotine Metabolism Ratio With Copd In Smokers Undergoing A Smoking Cessation Program

Background: Cigarette smoke is the main avoidable cause of COPD .Only a portion of patients who smoke and with a pack-year greater than 20 develop COPD. Aim: To determine if high nicotine metabolism ratio,3-hydroxycotinine/cotinine (NMR) >0.4 could be associated with COPD development and exacerbation risk. Methods: Eighty patients were recruited in a smoking cessation outpatients service. The patients underwent salivary cotinine and hydroxy-cotinine level detection by mass-spectrometry. Patients were also evaluated by spirometry . Results: the mean age was 53.8, the mean pack year was 34 and Fagestrom’s test mean value was 4.6. The CAT questionnaire mean score was 16.5, and the mean body mass index (BMI) value was 25.4. Patients COPD were found to be nicotine metabolizers faster than patients without COPD with OR 3.3 (table 1) ( p <0.01) and the Fagestrom’s test moderate level was also reported to be associated with high NMR (ratio>0.4) in comparison with mild level ( p<0.03). The CAT questionnaire score > 10 versus CAT<10 was also associated with higher NMR (p<0.04). In a logistic regression analysis a significant influence of mMRC (p<0.03), pack-year (p<0.04) , CAT (p<0.04) on COPD development were also found as well as NMR ratio and exhaled CO(p<0.05).