Date Published: June 11, 2018
Publisher: Public Library of Science
Author(s): Jae Won Hong, Jung Hyun Noh, Dong-Jun Kim, Susan M. Pinney.
Smoking rate based on self-reporting questionnaire might be underestimated. Cotinine is the principal metabolite of nicotine and is considered an accurate biomarker of exposure to cigarette smoke.
This study evaluated the prevalence of and factors associated with urinary cotinine-verified smoking in Korean adults.
We analyzed data from 12,110 adults in the 2008–2011 Korea National Health and Nutrition Examination Survey (KNHANES), using three threshold levels of urinary cotinine ≥100ng/ml, ≥50ng/ml, and ≥30ng/ml.
The weighted prevalence of urinary cotinine levels of ≥100, ≥50, and ≥30 ng/mL in the whole study population was 34.7%, 37.1%, and 41.1%, respectively. Male sex, younger age, elementary school graduation, household income in the ≤24th percentile, service and sales workers and assembly workers, and high-risk alcohol drinking were associated with a higher prevalence of urinary cotinine level of ≥ 50 or 30 ng/mL, after we adjusted for age, sex, education level, number of family members, household income, occupation, and alcohol drinking.
Based on a threshold urinary cotinine level of 50 ng/mL, the prevalence of cotinine-verified smoking in a representative sample of Korean adults was 37.1% (men 52.7%, women 15.4%). Younger age, male sex, low education level, service and sales workers, low household income, and high-risk alcohol drinking were associated with the risk of smoking.
Assessing smoking status is important in epidemiological studies of smoking, clinical studies of smoking-related diseases, and the monitoring of smoking cessation interventions. Previous studies on smoking have generally involved self-report questionnaires, which are noninvasive and inexpensive.
Using data from KNHANES 2008–2011 and a standardized threshold urinary cotinine level of 50 ng/mL, we found that the prevalence of cotinine-verified smoking was 37.1% (men 52.7%, women 15.4%), with the highest prevalence (58.0%) in men 19–44 years of age, in a representative sample of Korean adults. In KNHANES 2011, the prevalence of smoking among men and women was 47.3% and 6.8%, respectively, as determined using health interviews.