Sex related differences in cigarette smoking nondisclosure and serum cotinine levels
Introduction: Cigarette smoking self-reports have been regularly questioned for social desirability response bias, thus challenging the validity of epidemiological studies that use self-reports as exposure. Methods: The authors analyzed self-reports, serum cotinine and tobacco consumption data on 493 men and 489 women recruited in a 2005-2009 prospective pregnancy cohort study using receiver operating characteristic curve, linear ANCOVA plot and Wilson score intervals. Nondisclosure was defined as self-reporting as non-smoker but having serum cotinine level higher than cut-off. Results: Nondisclosure was significantly higher in male smokers (20.88%; 95% CI: 13.79, 30.32) than female smokers (5.26%; 95% CI: 1.81, 14.37) using already established serum cotinine cut-offs (1.78 ng/mL for males and 4.47 ng/mL for females). Compared with male smokers, female smokers had lower average serum cotinine levels [218.42 (185.29,252.89) vs 140.21 (110.29,171.78); p<0.01] with no significant difference in average number of cigarettes smoked per day [9.78 (7.90, 11.67) vs 8.80 (6.52, 11.07); p=0.51]. The optimal cut-offs for differentiating smokers and non-smokers were calculated for men and women as 15.16 ng/mL (88.9% Sensitivity, 72.7% Specificity) and 7.14 ng/mL (92.6% Sensitivity, 88.5% Specificity) respectively. Analyzing with new cut-offs showed a lower estimate of nondisclosure but it still remained significantly higher in male smokers [15.79% (9.27,25.60)] than female smokers [5.66% (1.94, 15.37)]. Conclusion: Cigarette smoking self-report is not an accurate measure of tobacco exposure. Additionally, significant sex related differences exist in serum cotinine levels among smokers suggesting that self-reports may overestimate the tobacco exposure and risk of associated diseases in women compared with men.
Public health or related research
Social and behavioral sciences
Analyze the cigarette smoking nondisclosure rates with self-reports and serum cotinine levels using the established serum cotinine cut-offs among couples trying to become pregnant.
Identify the characteristics of male and female smokers in general and in relation to their disclosure status.
Compare the serum cotinine levels for the same number of cigarettes smoked per day in male and female smokers.
Define new serum cotinine cut-offs for differentiating smokers and non-smokers in both men and women.
Compare the nondisclosure rates of male and female smokers using the established and newly defined serum cotinine cut-offs.
Keyword(s): Smoking, Reproductive Health
Presenting author's disclosure statement:
Qualified on the content I am responsible for because: I am a Masters student with two years of experience in epidemiological research. I have also obtained an MBBS degree (equivalent to M.D in USA) from India and have in-depth knowledge of cigarette smoking and its metabolism. My research interests have been in understanding the role of environmental factors in disease pathology and developing better screening procedures.
Any relevant financial relationships? No
I agree to comply with the American Public Health Association Conflict of Interest and Commercial Support Guidelines,
and to disclose to the participants any off-label or experimental uses of a commercial product or service discussed
in my presentation.