Estimation of urinary cotinine cut-off points distinguishing non-smokers, passive and active smokers

Abstract

An objective assessment of exposure to tobacco smoke may be accomplished by means of examining particular biomarkers in body fluids. The most common biomarker of tobacco smoke exposure is urinary, or serum, cotinine. In order to distinguish non-smokers from passive smokers and passive smokers from active smokers, it is necessary to estimate cotinine cut-off points. The objective of this article was to apply statistical distribution of urinary cotinine concentration to estimate cut-off points distinguishing the three above-mentioned groups. The examined group consisted of 327 volunteers (187 women and 140 men) who were ethnically homogenous inhabitants of the same urban agglomeration (Sosnowiec, Poland). The values which enabled differentiation of the examined population into groups and subgroups were as follows: 50 microg l(-1) (differentiation of non-smokers from passive smokers), 170 microg l(-1) (to divide the group of passive smokers into two subgroups: minimally and highly exposed to environmental tobacco smoke), 550 microg l(-1) (differentiation of passive smokers from active smokers), and 2100 microg l(-1) (to divide group of active smokers into two subgroups: minimally and highly exposed to tobacco smoke). The results suggest that statistical distribution of urinary cotinine concentration is useful for estimating urinary cotinine cut-off points and for assessing the smoking status of persons exposed to tobacco smoke.

Self‐Reported Smoking, Urine Cotinine, and Risk of Cardiovascular Disease: Findings From the PREVEND (Prevention of Renal and Vascular End‐Stage Disease) Prospective Cohort Study

“…Other strengths include the relatively large sample size, which was also representative of the general population; the extended follow‐up enabling time‐to‐event analyses; exclusion of individuals with a baseline history of CVD; and measurements on a comprehensive panel of cardiovascular risk markers that enabled adequate adjustment for potential confounding. The cutoffs we employed to distinguish between no smoking and active smoking were appropriate (have high sensitivity and specificity values), conservative, and have been used in several previous studies 30, 31, 32, 33, 49. To enhance the validity of the findings, we restricted analyses to people with complete information on exposures, risk factors, and outcomes.…”

“…We categorized cotinine‐assessed smoking exposure as never smokers, former smokers, light current smokers, and heavy current smokers on the basis of cutoffs for urine cotinine reported in the literature. The cutoffs for urine cotinine were <100 ng/mL, 100 to 500 ng/mL, and >500 ng/mL for the categories of never smokers, former smokers, and current smokers, respectively, as employed in several previous reports 30, 31, 32, 33. Current smokers were then subdivided into light and heavy current smokers on the basis of the median cotinine level in current smokers, as reported in a previous study 31.…”

Biochemically-verified Smoking Rate Trends and Factors Associated with Inaccurate Self-reporting of Smoking Habits in Korean Women

“…A major metabolite of nicotine that is present in tobacco smoke, cotinine has a half-life of 16 to 20 hours in the body but can remain in the system for up to 2 weeks (Zielinska-Danch et al, 2007). The concentration of cotinine found in the serum, urine, or even saliva is directly related to the extent of an individual's smoking.…”

Can Urinary Cotinine Predict Nicotine Dependence Level in Smokers?

“…However, as those studies primarily focused on a simple linear correlation, there is a lack of data showing how cotinine levels independently predict severity of nicotine dependence after adjustment of potential confounding factors. Furthermore, the standard cut-off values for cotinine levels as an indicator of high nicotine dependence have not been set yet, whereas there have been mainly several reports on urinary cotinine cut-off points discriminating non-smokers/smokers or passive/ active smokers (Zielinska-Danch et al, 2007).…”