Serum cotinine and urinary 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanonol levels among non-Hispanic Asian American smokers and nonsmokers as compared to other race/ethnicities: data from NHANES 2011-2012

Concentrations of serum hydroxycotinine for US adult smokers aged ≥ 20 years by type of smoker

Cross-sectional survey data (N = 3264) from the National Health and Nutrition Examination Survey for 2013-2018 were used to investigate how serum hydroxycotinine concentrations vary among US adult smokers aged ≥ 20 years by smoker type. Those reporting using tobacco products during the last 5 days were classified as smokers. Smokers were classified as being cigarette only smokers, cigar only smokers, cigar and cigarette smokers, dual cigarette and e-cigarette smokers, e-cigarette only smokers, smokeless tobacco only users, and all other smokers. Regression models stratified by smoker type with log10 transformed values of serum hydroxycotinine as dependent variable were fitted to compute adjusted geometric means (AGM) for each type of smoker. The order in which various types of smokers were found to have AGMs for serum hydroxycotinine was cigarette and e-cigarette users (64.61 ng/mL), cigarette only smokers (53.17 ng/mL), smokeless tobacco only users (44.89 ng/mL), cigar and cigarette smokers (36.99 ng/mL), e-cigarette only users (32.52 ng/mL), smokers of miscellaneous tobacco products (20.32 ng/mL), and cigar smokers only (10.75 ng/mL). Compared to this as presented in a recent study, the order in which serum cotinine AGMs were: smokeless tobacco only users (272 ng/mL), cigarette only smokers (152.5 ng/mL), cigarette-e-cigarette or e-cigarette only users (146.3 ng/mL), smokers of miscellaneous tobacco products (105.5 ng/mL), cigar and cigarette smokers (92.5 ng/mL), cigar smokers only (65.1 ng/mL). Among cigarette only smokers, males had lower AGM than females (47.18 vs. 59.91 ng/mL, p < 0.01), but the reverse was true for smokeless tobacco only and miscellaneous smokers. In general, differences for hydroxycotinine levels did not exist among non-Hispanic white and non-Hispanic black smokers. Among US adults, cigarette only and dual cigarette-e-cigarette smokers had the highest, and cigar smokers had the lowest concentrations of serum hydroxycotinine.

Comparative analysis of the concentrations of serum cotinine and hydroxycotinine for US children, adolescents, and adults: impact of exposure to environmental tobacco smoke at home and other indoor environments

This study was carried out to investigate how serum cotinine and hydroxycotinine concentrations compare and vary by age, gender, race/ethnicity, smoking, and exposure to environmental tobacco smoke (ETS) at home and other indoor environments. Data from NHANES for 2013-2018 for US children aged 3-11 years (N = 3834), nonsmoker (N = 1963) and smoker (N = 247) adolescents aged 12-19 years, and nonsmoker (N = 10,334) and smoker (N = 3264) adults aged ≥ 20 years were analyzed by fitting regression models with log10 transformed values of serum cotinine and hydroxycotinine as dependent variables. Models stratified by age and smoking status were fitted. Those reporting using tobacco products during the last 5 days were classified as smokers. For cotinine, males had higher cotinine concentrations than females for children, adolescent smokers, and nonsmoker adults. Non-Hispanic Blacks were found to have lower concentrations of both cotinine and hydroxycotinine than non-Hispanic Whites for adult smokers (p < 0.01) only. The ratio of concentrations of those exposed to ETS at home to those not exposed to ETS at home for hydroxycotinine was 6.3 for nonsmoker adults and as low as 1.39 for adult smokers.

Re-visiting serum cotinine concentrations among various types of smokers including cigarette only smokers: some new, previously unreported results

Data (N = 11614) from National Health and Nutrition Examination Survey (NHANES) for 1999-2016 for US adults aged ≥ 20 years were analyzed by fitting regression models to estimate unadjusted and adjusted geometric means (AGM) for several different groups of smokers. Serum cotinine level ≥ 3.3 ng/mL was used to distinguish smokers from nonsmokers. AGMs for cigarette only, cigar only, dual cigarette/cigar, e-cigarette or dual e-cigarette/cigarette, and smokeless tobacco only smokers were estimated to be 152.5, 65.1, 92.5, 146.3, and 272.0 ng/mL, respectively. Males were found to have higher cotinine levels than females for dual cigarette and cigar smokers, but the reverse was observed for smokeless tobacco users. Non-Hispanic blacks had higher AGMs than non-Hispanic whites for cigarette only smokers, but the reverse was observed for dual cigarette and cigar smokers. For the first time, serum cotinine estimates for those self-reported nonsmokers who were classified to be smokers (29.4 ng/mL) and those smokers for whom self-reported data for use of tobacco products were missing were also estimated (113.8 ng/mL).

Concentrations of serum cotinine across stages of glomerular function among US adult smokers and nonsmokers

Data from National Health and Nutrition Examination Survey for 1999-2016 were used to investigate variabilities in serum cotinine levels for US adult smokers (N = 8951) and nonsmokers (N = 28,205) aged ≥ 20 years across the stages of glomerular function (GF). Those with serum cotinine levels < 3.3 ng/mL and did not report using any tobacco products during the last 5 days were classified as nonsmokers. Those with serum cotinine levels ≥ 3.3 ng/mL and reported using cigarettes, cigars, pipes, and/or water pipes with or without using e-cigarettes and/or smokeless tobacco products during the last 5 days were classified as nonsmokers. Those who had eGFR > 90 mL/min/1.73 m² were classified to be in GF stage 1 or GF-1, those with 60 ≤ eGFR ≤ 90 mL/min/1.73 m² were classified to be in GF-2, those with 45 ≤ eGFR < 60 mL/min/1.73 m² were classified to be in GF-3A, and those with 15 ≤ eGFR <45 mL/min/1.73 m² were classified to be in GF-3B/4. Among nonsmokers, except for females and non-Hispanic blacks, adjusted levels of serum cotinine (AGM) decreased relatively sharply from GF-1 to GF-2, stayed relatively stable at GF-2 and GF-3A, and then rose moderately to GF-3B/4. For example, for non-Hispanic whites, AGMs were 0.042, 0.033, 0.031, and 0.037 ng/mL at GF-1, GF-2, GF-3A, and GF-3B/4 respectively. Among smokers, except for females and non-Hispanic blacks, AGMs increased relatively sharply from GF-1 to GF-2 and then decreased from GF-2 to GF-3/4. For example, for males, AGMs were 151.9, 192.0, and 162.9 ng/mL at GF-1, GF-2, and GF-3/4 respectively. AGMs for male smokers were lower than for female smokers at GF-3/4 (162.9 vs. 197.2 ng/mL, p < 0.01). The order of AGMs by race/ethnicity was non-Hispanic blacks > non-Hispanic whites > Hispanics and others at every GF stage. AGMs at GF-3/4 were higher than AGMs at GF-1 for smokers.

Chronic Cigarette Smoking Associates Directly and Indirectly with Self-Reported Olfactory Alterations: Analysis of the 2011-2014 National Health and Nutrition Examination Survey

INTRODUCTION

Population-based studies show inconsistent effects of cigarette smoking on olfactory function. We aimed to identify direct and indirect associations between measures of smoking exposure/nicotine dependence and altered olfaction in a nationally representative sample of adults.

METHODS

NHANES 2011-2014 (n = 7418) participants (mean age = 57.8 ± 12.2 years) self-reported olfaction and related health and demographic risks. Affirmative answers to three questions defined altered olfaction (olfactory problems in the past years; worse ability since age 25; phantom smells). Smoking (never, former, current) was self-reported by chronicity (pack years, PY) and dependency (time to first cigarette upon waking) and verified by serum cotinine. Associations were tested with logistic regression, reporting odds ratios (ORs) and 95% confidence intervals (CIs), and mediation models.

RESULTS

Estimated prevalence of altered olfaction was 22.3%, with age-related increases. Nearly half of the sample were former/current smokers (47.4%). Controlling for olfactory-related risks, ≥10 PY smokers had significantly greater odds of altered olfaction versus never smokers (OR 1.36, CI: 1.06-1.74). The odds of altered olfaction were heightened among current smokers (≥10 PY) who also had high nicotine dependence (smoked ≤30 min of waking) (OR 1.41, CI: 1.01-1.99). Light smokers (≤10 PY smokers) did not show increased odds versus never smokers. Current smokers who also were heavy drinkers (≥4 drinks/day) had the highest odds for altered olfaction (OR 1.96, CI: 1.20-3.19). Olfactory-related pathologies (sinonasal problems, serious head injury, tonsillectomy, xerostomia) partially mediated the association between smoking and altered olfaction.

CONCLUSIONS

Chronic cigarette smoking was associated with increased odds of self-reported olfactory alterations, directly and indirectly via olfactory-related pathologies.

IMPLICATIONS

Analysis of the US nationally representative data revealed significant positive associations between chronic smoking and alterations in the sense of smell. Rates of smell alteration (self-reported problems in the past year, losses with aging, and phantom smells) increased from 23% among adults to 33% for chronic smokers and 38% for chronic smokers who also reported heavy drinking. Chronic smoking showed associations with smell alteration that were direct and indirect through exposure to olfactory-related pathologies (naso-sinus problems, dry mouth, head/facial injury). Smell alteration can impact smokers' quality of life by challenging the ability to sense warning odors, food flavor, and olfactory-stimulated emotions and memories.

Biomarkers of Exposure to Secondhand and Thirdhand Tobacco Smoke: Recent Advances and Future Perspectives

Smoking is the leading preventable disease worldwide and passive smoking is estimated to be the cause of about 1.0% of worldwide mortality. The determination of tobacco smoke biomarkers in human biological matrices is key to assess the health effects related to the exposure to environmental tobacco smoke. The biomonitoring of cotinine, the main nicotine metabolite, in human biofluids-including urine, serum or saliva-has been extensively used to assess this exposure. However, the simultaneous determination of cotinine together with other tobacco biomarkers and the selection of alternative biological matrices, such as hair, skin or exhaled breath, would enable a better characterization of the kind and extent of tobacco exposure. This review aims to perform a critical analysis of the up-to-date literature focused on the simultaneous determination of multiple tobacco smoke biomarkers studied in different biological matrices, due to the exposure to secondhand smoke (SHS) and thirdhand smoke (THS). Target biomarkers included both tobacco-specific biomarkers-nicotine and tobacco specific nitrosamine biomarkers-and tobacco-related biomarkers, such as those from polycyclic aromatic hydrocarbons, volatile organic compounds, metals and carbon monoxide. To conclude, we discuss the suitability of determining multiple biomarkers through several relevant examples of SHS and THS exposure.

Low Cotinine Glucuronidation Results in Higher Serum and Saliva Cotinine in African American Compared to White Smokers

Background: Tobacco exposure is often quantified by serum or saliva concentrations of the primary nicotine metabolite, cotinine. However, average cotinine concentrations are higher in African Americans (AA) compared with Whites with similar smoking levels. Cotinine is metabolized by UGT2B10 and CYP2A6, and low UGT2B10 activity is common in AA, due to the prevalence of a UGT2B10 splice variant.Methods: UGT2B10 activity was phenotyped in 1,446 smokers (34% AA) by measuring the percentage of cotinine excreted as a glucuronide. Urinary total nicotine equivalents (TNE), the sum of nicotine and 6 metabolites, were determined to quantify smoking dose, and cotinine and 3'-hydroxycotinine were quantified in saliva (study 1) or serum (study 2).Results: Ninety-seven smokers (78% AA) were null for UGT2B10 activity, and the saliva and serum cotinine levels, after adjustment for TNE and cigarettes per day (CPD), were 68% and 48% higher in these smokers compared with nonnull smokers (P < 0.001). After adjustment for TNE and CPD, salivary cotinine was 35% higher, and serum cotinine 24% higher in AA versus White smokers, but with additional adjustment for UGT2B10 activity, there were no significant differences in saliva and serum cotinine concentrations between these two groups.Conclusions: UGT2B10 activity significantly influences plasma cotinine levels, and higher cotinine concentrations in AA versus White smokers (after adjustment for smoking dose) result from lower levels of UGT2B10-catalyzed cotinine glucuronidation by AA.Impact: UGT2B10 activity or genotype should be considered when using cotinine as a tobacco exposure biomarker, particularly in populations such as AA with high frequencies of UGT2B10 nonfunctional variants. Cancer Epidemiol Biomarkers Prev; 26(7); 1093-9. ©2017 AACR.

Evaluating the relationship between biomarkers of potential harm and biomarkers of tobacco exposure among current, past, and nonsmokers: data from the National Health and Nutrition Examination Survey 2007-2012

Potential long-term health effects from tobacco products can be estimated by measuring changes in biochemical indicators of disease mechanisms like inflammation. This study assesses the potential relationships between biomarkers of potential harm (BOPH) and biomarkers of cigarette smoke exposure (BOE) based on data from the NHANES (2007-2012, n = 17,293 respondents). Statistically significant relationships were observed between white blood cells (WBC) and high-density lipoprotein (HDL) and BOE; between WBC and high-sensitivity C-reactive protein and smoking status; and between WBC and HDL and smoking intensity. This analysis suggests that WBC and HDL are useful BOPH in studies assessing the health risks of cigarette smoking.

Distributions of selected urinary metabolites of volatile organic compounds by age, gender, race/ethnicity, and smoking status in a representative sample of U.S. adults

Data from National Health and Nutrition Examination Survey for the years 2011-2012 were used to evaluate variability in the observed levels of 19 urinary metabolites of 15 parent volatile organic compounds (VOCs) by age, gender, race/ethnicity, and smoking status. Smokers were found to have statistically significantly higher adjusted levels than nonsmokers for selected urinary metabolites of acrolein, acrylamide, acrylonitrile, 1,3-butadiene, carbon-disulfide, crotonaldehyde, cyanide, N,N-dimethylformamide, ethylbenzene-styrene, propylene oxide, styrene, and xylene. Female nonsmokers were found to have lower adjusted levels of selected metabolites of acrolein, carbon-disulfide, and N,N-dimethylformamide than male nonsmokers but female smokers had higher levels of each of these metabolites than male smokers. In addition, female smokers also had higher adjusted levels of selected metabolites of 1,3-butadiene, crotonaldehyde, cyanide, and ethylbenzene-styrene. Thus, constituents other than VOCs in tobacco smoke affect excretion of certain VOC metabolites differently among males and females. Non-Hispanic whites (NHW) had higher adjusted levels than non-Hispanic blacks (NHB) for 8 metabolites. NHB had statistically significantly lower adjusted levels than Hispanics for 5 VOC metabolites and lower levels than non-Hispanic Asians (NHAS) for 6 metabolites. Hispanics had statistically significantly higher levels than NHAS for 5 metabolites. Levels of 11 of the 19 metabolites analyzed increased with increase in age. Exposure to environmental tobacco smoke at home was associated with increased levels of 9 metabolites. Increase in the number of days tobacco products were used during the last five days was associated with increased levels of 12 of the 19 VOC metabolites.

Exposure to second hand smoke at home and work among nonsmokers

Exposure to second hand smoke (SHS) is associated with adverse health effects. This study was undertaken to assess comparative levels of exposure to SHS at home and work among nonsmokers aged ⩾12 years. Data from National Health Examination Survey for 1999-2010 were analyzed to estimate exposure to SHS. Total number of subjects included in the study was 24,791. Those who self-reported not having used any tobacco products during the last five days were considered nonsmokers for the purpose of this study. Serum cotinine levels were used as the outcome variable to indicate the level of exposure to SHS. Adjusted serum cotinine levels for those with no exposure to SHS, exposure to SHS at work only, exposure to SHS at home only, and exposure to SHS at home and work were 0.047 (0.044-0.050)n g/mL, 0.055 (0.047-0.064) ng/mL, 0.522 (0.401-0.678) ng/mL, and 0.485 (0.280-0.0840) ng/mL respectively. Public efforts to reduce exposure to SHS at home should be strengthened.