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Comparison of biomarkers of exposure among US adult smokers, users of electronic nicotine delivery systems, dual users and nonusers, 2018–2019

Holt, Nathan M., Shiffman, Saul, Black, Ryan A., Goldenson, Nicholas I., Sembower, Mark A., Oldham, Michael J.·2023·Scientific Reports

Abstract

The harm caused by cigarette smoking is overwhelmingly due to byproducts of tobacco combustion. Electronic Nicotine Delivery Systems (ENDS) provide nicotine to users without combustion, and may support tobacco harm reduction among cigarette smokers who would not otherwise quit in the near term. Analyses of Wave 5 of the Population Assessment of Tobacco and Health (PATH) Study compared biomarkers of exposure (BOE) levels for nicotine, 3 metals, 2 tobacco-specific nitrosamines and 14 smoking-related volatile organic compounds in 151 exclusive ENDS users, 1341 exclusive cigarette smokers, 115 dual users (cigarettes and ENDS), and 1846 past 30-day nonusers of tobacco, adjusting for demographics. Nicotine exposure in ENDS users and dual users did not significantly differ from smokers. Among ENDS users, 16 of 18 other BOEs were significantly lower than smokers’; 9 BOEs were not significantly different from nonusers. Among dual users smoking < 10 cigarettes/day, 15 of 18 non-nicotine BOEs were significantly lower than smokers’, whereas in dual users smoking ≥ 10 cigarettes per day none of the BOEs significantly differed from smokers’. In this representative sample of US adults, exclusive use of ENDS (vs. cigarette smoking) was associated with much lower exposures to many harmful chemicals associated with smoking-related disease. BOE levels in dual users were directly related to their cigarette consumption. These BOE data provide further evidence that ENDS expose users to substantially lower levels of toxicants than combustible cigarettes, confirming their potential for harm reduction.

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Figure 1 Nicotine equivalents among smokers, ENDS users, dual users stratified by cigarettes/day and tobacco nonusers (weighted adjusted geometric mean and 95% confidence interval). Note. Groups whose bars do not share a letter above the bar are significantly different (p < 0.05). Groups whose bars share a letter do not significantly differ from each other (p ≥ 0.05). Geometric mean ratios, and more exact p-values are shown in Table S6 in the Supplemental Materials. Adjusted geometric means and confidence interval endpoints were derived from a weighted regression analysis with covariates for age, sex, race/ethnicity, and BMI and were computed by exponentiating predicted population margins with covariate values fixed at the observed means. The analysis was weighted to represent the US adult civilian, noninstitutionalized population of never, current, and recent (within 1-year) former tobacco users. Current Smokers: TNE2, N = 1341; TNE6, N = 1327. 10 + CPD Dual Users: TNE2, N = 61; TNE6, N = 61. < 10 CPD Dual Users: TNE2, N = 54; TNE6, N = 53. Current ENDS Users: TNE2, N = 151; TNE6, N = 146. Past 30-day Nonusers: TNE2, N = 1842; TNE6, N = 152.
Figure 1 Nicotine equivalents among smokers, ENDS users, dual users stratified by cigarettes/day and tobacco nonusers (weighted adjusted geometric mean and 95% confidence interval). Note. Groups whose bars do not share a letter above the bar are significantly different (p < 0.05). Groups whose bars share a letter do not significantly differ from each other (p ≥ 0.05). Geometric mean ratios, and more exact p-values are shown in Table S6 in the Supplemental Materials. Adjusted geometric means and confidence interval endpoints were derived from a weighted regression analysis with covariates for age, sex, race/ethnicity, and BMI and were computed by exponentiating predicted population margins with covariate values fixed at the observed means. The analysis was weighted to represent the US adult civilian, noninstitutionalized population of never, current, and recent (within 1-year) former tobacco users. Current Smokers: TNE2, N = 1341; TNE6, N = 1327. 10 + CPD Dual Users: TNE2, N = 61; TNE6, N = 61. < 10 CPD Dual Users: TNE2, N = 54; TNE6, N = 53. Current ENDS Users: TNE2, N = 151; TNE6, N = 146. Past 30-day Nonusers: TNE2, N = 1842; TNE6, N = 152.CC BY · PubMed Central
Figure 2 BOEs of tobacco-specific nitrosamines among smokers, ENDS users, dual users stratified by cigarettes/day and past 30-day nonusers (weighted adjusted geometric mean and 95% confidence interval). Note. Groups whose bars do not share a letter above the bar are significantly different (p < 0.05). Groups whose bars share a letter do not significantly differ from each other (p ≥ 0.05). Geometric mean ratios, and more exact p-values are shown in Table S6 in the Supplemental Materials. Adjusted geometric means and confidence interval endpoints were derived from a weighted regression analysis with covariates for age, sex, race/ethnicity, and BMI and were computed by exponentiating predicted population margins with covariate values fixed at the observed margins. The analysis was weighted to represent the US adult civilian, noninstitutionalized population of never, current, and recent (within 1-year) former tobacco users. Current Smokers: NNAL, N = 1338; NNN, N = 1309. 10 + CPD Dual Users: NNAL, N = 60; NNN, N = 58. < 10 CPD Dual Users: NNAL, N = 54; NNN, N = 53. Current ENDS Users: NNAL, N = 149; NNN, N = 148. Past 30-day Nonusers: NNAL, N = 1828; NNN, N = 1836.
Figure 2 BOEs of tobacco-specific nitrosamines among smokers, ENDS users, dual users stratified by cigarettes/day and past 30-day nonusers (weighted adjusted geometric mean and 95% confidence interval). Note. Groups whose bars do not share a letter above the bar are significantly different (p < 0.05). Groups whose bars share a letter do not significantly differ from each other (p ≥ 0.05). Geometric mean ratios, and more exact p-values are shown in Table S6 in the Supplemental Materials. Adjusted geometric means and confidence interval endpoints were derived from a weighted regression analysis with covariates for age, sex, race/ethnicity, and BMI and were computed by exponentiating predicted population margins with covariate values fixed at the observed margins. The analysis was weighted to represent the US adult civilian, noninstitutionalized population of never, current, and recent (within 1-year) former tobacco users. Current Smokers: NNAL, N = 1338; NNN, N = 1309. 10 + CPD Dual Users: NNAL, N = 60; NNN, N = 58. < 10 CPD Dual Users: NNAL, N = 54; NNN, N = 53. Current ENDS Users: NNAL, N = 149; NNN, N = 148. Past 30-day Nonusers: NNAL, N = 1828; NNN, N = 1836.CC BY · PubMed Central
Figure 3 BOEs of VOCs among smokers, ENDS users, dual users stratified by CPD and past 30-day nonusers (weighted adjusted geometric mean and 95% confidence interval). Note. All values represent μg/g creatinine. Groups whose bars do not share a letter above the bar are significantly different (p < 0.05). Groups whose bars share a letter do not significantly differ from each other (p ≥ 0.05). Geometric mean ratios, and more exact p-values are shown in Table S6 in the Supplemental Materials. Adjusted geometric means and confidence interval endpoints were derived from a weighted regression analysis with covariates for age, sex, race/ethnicity, and BMI and were computed by exponentiating predicted population margins with covariate values fixed at the observed means. The analysis was weighted to represent the US adult civilian, noninstitutionalized population of never, current, and recent (within 1-year) former tobacco users. Current Smokers, N = 1341; 10 + CPD Dual Users, N = 61; < 10 CPD Dual Users, N = 54; ENDS Users, N = 151; Past 30-day Nonusers, N = 1846.
Figure 3 BOEs of VOCs among smokers, ENDS users, dual users stratified by CPD and past 30-day nonusers (weighted adjusted geometric mean and 95% confidence interval). Note. All values represent μg/g creatinine. Groups whose bars do not share a letter above the bar are significantly different (p < 0.05). Groups whose bars share a letter do not significantly differ from each other (p ≥ 0.05). Geometric mean ratios, and more exact p-values are shown in Table S6 in the Supplemental Materials. Adjusted geometric means and confidence interval endpoints were derived from a weighted regression analysis with covariates for age, sex, race/ethnicity, and BMI and were computed by exponentiating predicted population margins with covariate values fixed at the observed means. The analysis was weighted to represent the US adult civilian, noninstitutionalized population of never, current, and recent (within 1-year) former tobacco users. Current Smokers, N = 1341; 10 + CPD Dual Users, N = 61; < 10 CPD Dual Users, N = 54; ENDS Users, N = 151; Past 30-day Nonusers, N = 1846.CC BY · PubMed Central
Figure 4 BOEs of metals among smokers, ENDS users, dual users stratified by cigarettes/day and past 30-day nonusers (weighted adjusted geometric mean and 95% confidence interval). Note. Groups whose bars do not share a letter above the bar are significantly different (p < 0.05). Groups whose bars share a letter do not significantly differ from each other (p ≥ 0.05). Geometric mean ratios, and more exact p-values are shown in Table S6 in the Supplemental Materials. Adjusted geometric means and confidence interval endpoints were derived from a weighted regression analysis with covariates for age, sex, race/ethnicity, and BMI and were computed by exponentiating predicted population margins with covariate values fixed at the observed means. The analysis was weighted to represent the US adult civilian, noninstitutionalized population of never, current, and recent (within 1-year) former tobacco users. Current Smokers, N = 1341; 10 + CPD Dual Users, N = 61; < 10 CPD Dual Users, N = 54; ENDS Users, N = 151; Past 30-day Nonusers, N = 1845.
Figure 4 BOEs of metals among smokers, ENDS users, dual users stratified by cigarettes/day and past 30-day nonusers (weighted adjusted geometric mean and 95% confidence interval). Note. Groups whose bars do not share a letter above the bar are significantly different (p < 0.05). Groups whose bars share a letter do not significantly differ from each other (p ≥ 0.05). Geometric mean ratios, and more exact p-values are shown in Table S6 in the Supplemental Materials. Adjusted geometric means and confidence interval endpoints were derived from a weighted regression analysis with covariates for age, sex, race/ethnicity, and BMI and were computed by exponentiating predicted population margins with covariate values fixed at the observed means. The analysis was weighted to represent the US adult civilian, noninstitutionalized population of never, current, and recent (within 1-year) former tobacco users. Current Smokers, N = 1341; 10 + CPD Dual Users, N = 61; < 10 CPD Dual Users, N = 54; ENDS Users, N = 151; Past 30-day Nonusers, N = 1845.CC BY · PubMed Central

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Metadata

Authors
Holt, N. M., Shiffman, S., Black, R. A., Goldenson, N. I., Sembower, M. A., & Oldham, M. J.
Venue
Scientific Reports
Published
2023-05-05
Volume
13
Issue
1
ISSN
2045-2322
Cited by
54
References
2
Language
en
Funders
Juul Labs, Inc.

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