Cotinine Concentrations Research Articles

Anabasine and Anatabine Exposure Attributable to Cigarette Smoking: National Health and Nutrition Examination Survey (NHANES) 2013-2014.

Anabasine and anatabine are minor alkaloids in tobacco products and are precursors for tobacco-specific nitrosamines (TSNAs). The levels of these two compounds have been used to differentiate tobacco product sources, monitor compliance with smoking cessation programs, and for biomonitoring in TSNA-related studies. The concentrations of urinary anabasine and anatabine were measured in a representative sample of U.S. adults who smoked cigarettes (N = 770) during the 2013–2014 National Health and Nutrition Examination Survey (NHANES) study cycle, which was the first cycle where urinary anabasine and anatabine data became available. Weighted geometric means (GM) and geometric least squares means (LSM) with 95% confidence intervals were calculated for urinary anabasine and anatabine categorized by tobacco-use status [cigarettes per day (CPD) and smoking frequency] and demographic characteristics. Smoking ≥20 CPD was associated with 3.6× higher anabasine GM and 4.8× higher anatabine GM compared with smoking <10 CPD. Compared with non-daily smoking, daily smoking was associated with higher GMs for urinary anabasine (1.41 ng/mL vs. 6.28 ng/mL) and anatabine (1.62 ng/mL vs. 9.24 ng/mL). Urinary anabasine and anatabine concentrations exceeded the 2 ng/mL cut point in 86% and 91% of urine samples from people who smoke (PWS) daily, respectively; in comparison, 100% of them had serum cotinine concentrations greater than the established 10 ng/mL cut point. We compared these minor tobacco alkaloid levels to those of serum cotinine to assess their suitability as indicators of recent tobacco use at established cut points and found that their optimal cut point values would be lower than the established values. This is the first time that anabasine and anatabine are reported for urine collected from a U.S. population-representative sample of NHANES study participants, providing a snapshot of exposure levels for adults who smoked during 2013–2014. The results of this study serve as an initial reference point for future analysis of NHANES cycles, where changes in the national level of urinary anabasine and anatabine can be monitored among people who smoke to show the effect of changes in tobacco policy.

Situations of Passive Smoking by Urine Cotinine Levels and Recognition of Passive Smoking in High School Students -Effectiveness of Smoking Prevention Education Using a Video Made by High School Students

We investigated a situation of passive smoking and its damaging effects among high school students. Urine cotinine concentration was measured and quantified. Additionally, we evaluated the awareness of passive smoking and smoking regulations in high school students, and the educational effect on passive smoking using a questionnaire survey and educational videos produced by high school students. We conducted a self-reporting questionnaire survey with high school students before and after watching the video produced by the high school students. We gathered the scores of the Kano Social Nicotine Dependence Questionnaire (KTSND) and awareness of smoking restrictions. Consent was obtained through the questionnaire before watching the video and collecting urine samples. Urine cotinine concentrations from 54 samples were evaluated and indicated within the low value. The KTSND score significantly decreased for those who responded to both questionnaires, after watching the video. Furthermore, analysis of the KTSND questionnaire items showed a significant decrease in scores for lifestyle, stress, and smoking location. This suggests that the video produced in this study has a certain amount of educational effect on passive smoking and that the student-led educational method is effective. The survey using the KTSND revealed that there were some students who were not exposed to passive smoking, but instead had high smoking tolerance. Going forward, it will be necessary to promote education on passive smoking and smoking prevention by incorporating the video lecture and urine cotinine concentration was measured, as in this study, to encourage behavior that decreases passive smoking among high school students.

Pre- and postnatal exposure to secondhand tobacco smoke and body composition at 12 years: periods of susceptibility.

ObjectiveThe study aimed to identify periods of heightened susceptibility to the effects of pre‐ and postnatal secondhand tobacco smoke (SHS) exposure on body composition at age 12 years.MethodsThe study used data from 217 children from the Health Outcomes and Measures of the Environment (HOME) Study, a prospective cohort in Cincinnati, Ohio. Using multiple informant models, the study estimated associations of maternal serum cotinine (16 and 26 weeks of pregnancy) and child serum cotinine concentrations (at age 12, 24, 36, and 48 months) with measures of body composition obtained with anthropometry and dual‐energy x‐ray absorptiometry at 12 years. We examined whether there were differences between these associations for pre‐ and postnatal exposure periods and potential effect measure modification by sex.ResultsPostnatal cotinine concentrations were associated with higher weight, BMI, body fat and lean mass, waist circumference, and visceral, android, and gynoid fat. Each 10‐fold increase in postnatal cotinine was associated with 76% increased risk of overweight or obesity (95% CI: 1.13‐2.75). Associations between prenatal concentrations and measures of body composition at 12 years were generally null.ConclusionsPostnatal exposure to SHS may increase adolescent adiposity and lean mass. Future studies should determine whether early‐life exposures to SHS are associated with other cardiometabolic risk markers.

Changes in the salivary cotinine cut-offs to discriminate smokers and non-smokers before and after Spanish smoke-free legislation

IntroductionHigh levels of cotinine in non-smokers indicate passive exposure to tobacco smoke. This study aims to evaluate variations in salivary cotinine cut-offs to discriminate smokers and non-smokers before and after the implementation of smoke-free legislation (Law 28/2005 and Law 42/2010) in a sample of the adult population of Barcelona, Spain. MethodsThis longitudinal study analyzes salivary cotinine samples and self-reported information from a representative sample (n = 676) of the adult population from Barcelona before and after the approval of smoke-free legislation. We calculated the receiver operating characteristic (ROC) curves, to obtain optimal cotinine cut-off points to discriminate between smokers and non-smokers overall, by sex and age, and their corresponding sensitivity, specificity, and area under the curve. We used linear mixed-effects models, with individuals as random effects, to model the percentage change of cotinine concentration before and after the implementation of both laws. ResultsThe mean salivary cotinine concentration was significantly lower post-2010 law (−85.8%, p < 0.001). The ROC curves determined that the optimal cotinine cut-off points for discriminating non-smokers and smokers were 10.8 ng/mL (pre-2005 law) and 5.6 ng/mL (post-2010 law), with a post-2010 law sensitivity of 92.6%, specificity of 98.4%, and an area under the curve of 97.0%. The post-2010 law cotinine cut-off points were 5.6 ng/mL for males and 1.9 ng/mL for females. ConclusionThe implementation of Spanish smoke-free legislation was effective in reducing secondhand smoke exposure and, therefore, also in reducing the cut-off point for salivary cotinine concentration. This value should be used to better assess tobacco smoke exposure in this population.

Assessing changes in nicotine consumption over two years in a population of Hanoi by wastewater analysis with benchmarking biomarkers

Monitoring the actual change in consumption of nicotine (a proxy for smoking) in the population is essential for formulating tobacco control policies. In recent years, wastewater-based epidemiology (WBE) has been applied as an alternative method to estimate changes in consumption of tobacco and other substances in different communities around the world, with high potential to be used in resource-scarce settings. This study aimed to conduct a WBE analysis in Hanoi, Vietnam, a lower-middle-income-country setting known for high smoking prevalence. Wastewater samples were collected at two sites along a sewage canal in Hanoi during three periods: Period 1 (September 2018), Period 2 (December 2018–January 2019), and Period 3 (December 2019–January 2020). Concentrations of cotinine, 3-hydroxycotinine, and nicotine ranged from 0.73 μg/L to 3.83 μg/L, from 1.09 μg/L to 5.07 μg/L, and from 0.97 μg/L to 9.90 μg/L, respectively. The average mass load of cotinine estimated for our samples was 0.45 ± 0.09 mg/day/person, which corresponds to an estimated daily nicotine consumption of 1.28 ± 0.25 mg/day/person. No weekly trend was detected over the three monitoring periods. We found the amount of nicotine consumption in Period 1 to be significantly lower than in Period 2 and Period 3. Our WBE estimates of smoking prevalence were slightly lower than the survey data. The analysis of benchmarking biomarkers confirmed that cotinine was stable in the samples similar to acesulfame, while paracetamol degraded along the sewer canal. Further refinement of the WBE approach may be required to improve the accuracy of analyzing tobacco consumption in the poor sewage infrastructure setting of Vietnam.

Investigation of exposure biomarkers in human plasma following differing levels of tobacco-specific N-nitrosamines and nicotine in cigarette smoke

Tobacco-specific N-nitrosamines (TSNAs) are strong carcinogens widely found in tobacco products, environmental tobacco smoke, lake, and wastewater. The main objective of this study was to investigate the effects of cigarette smoke with different yields of TSNAs (NNK, NNN, NAT, NAB) and nicotine on the levels of biomarkers of exposure in smokers’ plasma. Three hundred healthy volunteers were recruited comprising 60 smokers of each of 3 mg, 8 mg and 10 mg ISO tar yield cigarettes and 60 smokers who smoked 10 mg, 8 mg, and 3 mg for 14 days sequentially and 60 non-smokers. All study participants were male, aged from 21 to 45 years old, and were recruited from a same unit in Hebei, China. We measured the levels of NNAL, NAT, NNN, NAB and cotinine in plasma from 240 smokers and 60 non-smokers using a novel method established by online two-dimensional solid phase extraction-liquid chromatography-tandem mass spectrometry. The results showed that NNAL, NAT, NNN, NAB and cotinine in the plasma of smokers smoking cigarette with low TSNAs and nicotine were lower than that with high TSNAs and nicotine. When smokers switched from higher to lower TSNA yields of cigarettes, their plasma NNAL, NAT, NNN, NAB levels significantly decreased. The plasma concentrations of NNAL were significantly correlated with those of cotinine, NNN, NAT and NAB for smokers (p < 0.001). Similarly, the plasma concentrations of cotinine were significantly correlated with those of NNN, NAT and NAB for smokers (p < 0.001). The plasma NNAL, NAT, NNN, NAB and cotinine levels for smokers were significantly higher than those for non-smokers. These findings suggested that the total NNAL, NNN, NAT, NAB and cotinine in plasma were valid and reliable biomarkers for human exposure to TSNAs and nicotine.

Assessment of passive human exposure to tobacco smoke by environmental and biological monitoring in different public places in Wuhan, central China.

Passive exposure to tobacco smoke is a global public health problem, while there are few data on public place monitoring and general population exposure assessment in central China. This study aimed to examine the levels of airborne nicotine (n=256) in ten kinds of different public places in Wuhan, central China, and assess short-term and long-term smoke exposure in 340 non-smokers aged 18-67 who worked in these public places using tobacco biomarkers [i.e., cotinine and 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanol (NNAL), respectively]. The highest median concentration of airborne nicotine (17.0μg/m3) was observed in internet cafes, approximately 304-fold of the lowest value found in nurseries (55.9ng/m3). Among the other studied public places, restaurants had the highest median concentrations (ng/m3) of airborne nicotine (3,120), followed by subway stations (810), hotels (624), government officess (286), middle schools (269), health institutions (268), public institutions (190), and primary schools (140). Urinary cotinine and NNAL were found in almost all the participants, and the highest concentrations were found in non-smokers from the internet cafes [specific gravity (SG)-corrected urinary median concentrations: 23.1ng/mL, geometric mean (GM): 24.1ng/mL, range: 0.62-1679ng/mL] for cotinine and 104pg/mL (GM: 97.6pg/mL, range: 32.3-236pg/mL) for NNAL, respectively]. Urinary cotinine concentrations in male non-smokers (median: 2.02ng/mL) were significantly higher than those in female non-smokers (1.44) (P<0.01). Participants aged 18-27 were detected with the highest urinary cotinine and NNAL concentrations. Urinary cotinine and NNAL concentrations were significantly correlated with daily and monthly working hours, respectively. Besides, a positive correlation was observed between log-transformed urinary concentrations of cotinine and NNAL (r=0.32, P<0.001). This is the first time to report matched data on airborne nicotine and urinary cotinine/NNAL among employees in different public places. This study demonstrated ubiquitous exposure to environmental tobacco smoke in the studied public places.

Nicotine and cotinine quantification after a 4-week inhalation of electronic cigarette vapors in male and female mice using UPLC-MS/MS.

To detect the cotinine and nicotine serum concentrations of female and male C57BL/6J mice after a 4-week exposure to electronic (e)-cigarette vapors using ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS). This experimental study was carried out at an animal facility and laboratories, College of Pharmacy, King Saud University, Riyadh, Saudi Arabia, between January and August 2020. A 4-week exposure to e-cigarettes was carried out using male and female mice and serum samples were obtained for cotinine and nicotine quantification using UPLC-MS/MS. The chromatographic procedures involved the use of a BEH HSS T3 C18 column (100mm x 2.1mm, 1.7 μm) with acetonitrile as a mobile phase and 0.1% formic acid (2:98 v/v). The applied methodology has highly efficient properties of detection, estimation, and extraction, where the limit of quantification (LOQ) for nicotine was 0.57 ng/mL and limit of detection (LOD) for nicotine was 0.19 ng/mL, while the LOQ for cotinine was 1.11 ng/mL and LOD for cotinine was 0.38 ng/mL. The correlation coefficient was r2>0.99 for both compounds. The average recovery rate was 101.6±1.33 for nicotine and 100.4±0.54 for cotinine, while the precision and accuracy for cotinine and nicotine were less than 6.1. The serum cotinine level was higher in males (433.7±19.55) than females (362.3±16.27). This study showed that the gender factor might play a crucial role in nicotine metabolism.

Effect of Second-Hand Smoke Exposure on Establishing Urinary Cotinine-Based Optimal Cut-Off Values for Smoking Status Classification in Korean Adults.

Regulations for banning smoking in indoor public places and workplaces have increased worldwide in recent years. A consecutive Korean National Health and Nutrition Examination Survey (KNHANES) between 2008 and 2018 showed a trend toward significant decreases in self-reported tobacco smoke exposure and measured urinary cotinine concentrations. We established and compared each optimal cut-off value for assessing the effect of second-hand smoke (SHS) exposure on establishing urinary cotinine-based cut-off values for smoking status classification in a population setting controlled for racial and cultural diversity, using four KNHANES datasets consisting of the 2008, 2011, 2014, and 2018 surveys. A total of 18,229 Korean participants aged >19 years with measured urinary cotinine concentrations were enrolled. Self-reports of current smoking status showed that the prevalence of current smokers decreased from 22.9% to 18.2% between 2008 and 2018. During this period, the median value of urinary cotinine in nonsmokers decreased from 5.86 µg/L to 0.48 µg/L, whereas the median value showed no remarkable decrease in current smokers. The AUC-based optimal cut-off values of urinary cotinine concentration for distinguishing current smokers from nonsmokers decreased from 86.5 µg/L to 11.5 µg/L. Our study showed that decreased SHS exposure would result in decreased optimal cut-off values for distinguishing current smokers from nonsmokers. In addition, the study suggests that the range of urinary cotinine concentration to define SHS exposure for the trend monitoring of populationof SHS exposure is appropriate between 0.30 µg/L and 100 µg/L. In addition, our study showed the importance of determination of cotinine concentration, which would have allowed us to avoid mistakes in qualification to the study group in an increased use of e-cigarette setting.

A novel approach to assessing the effects of smoking on treatment response rate in muscle-invasive bladder cancer.

e16554 Background: Cigarette smoking is the strongest modifiable risk factor for bladder cancer and has been implicated in mechanisms of chemotherapy resistance. Prior studies examining tobacco exposure on chemotherapy response were limited by use of retrospective design and self-report assessment of smoking status, potentially under-estimating the association and risking bias towards the null. Cotinine is the central metabolite of nicotine and can be detected in saliva for up to 4 days after tobacco use. In this prospective cohort study, we tested the association between salivary cotinine level and pathologic response to neoadjuvant chemotherapy, assessed post-chemotherapy at the time of cystectomy, among patients with muscle-invasive bladder cancer (MIBC). Methods: Thirty-one patients with MIBC were prospectively recruited and surveyed on their smoking habits. Salivary cotinine was measured during chemotherapy using NicAlert test strips with cotinine concentration &gt; 10ng/mL indicating active smoking (cotinine = 1) and cotinine concentration &lt; 10ng/mL indicating no evidence of active tobacco use (cotinine = 0). Primary outcome was pathologic response at cystectomy, defined as complete response (pT0) or residual disease (pT1-4 or node+). For patients with prior history of tobacco use, the association between pre-chemotherapy cotinine level and post-chemotherapy response at cystectomy was assessed using a chi-squared test and an odds ratio with a 95% confidence interval (CI) using the Baptista-Pike method. Results: Thirty-one patients had cotinine levels measured during chemotherapy and 25 reported prior history of smoking. Of these 25 patients, 17 patients denied active smoking, 2 of whom had cotinine levels = 1 during chemotherapy. Response to chemotherapy by cotinine level among patients with prior history of tobacco use are shown in table 1. One patient declined cystectomy and was excluded from the analysis. The odds ratio of a complete response at cystectomy for patients with cotinine = 0 vs. cotinine = 1 was 3.86 (95% CI: 0.54-22.05) (p = 0.148). The odds ratio of residual disease with cotinine = 0 vs. cotinine = 1 was 0.26 (95% CI: 0.045-1.86) (p = 0.148). Conclusions: Prior smokers with no evidence of active tobacco use during curative chemotherapy were more than three-times as likely to demonstrate a complete response at the time of cystectomy compared to those with evidence of current tobacco use based on salivary cotinine levels. While this study was limited by a small sample size, it highlights a novel approach to tobacco use monitoring and the importance of continued smoking cessation counseling in patients with bladder cancer even after the diagnosis of cancer is made.[Table: see text]

Home gardens and distances to nature associated with behavior problems in alpine schoolchildren: Role of secondhand smoke exposure and biomarkers

Behavior problems in children are shaped by a complex intertwining of environmental, social, and biological factors. This study investigated whether more nature exposure was associated with less behavior problems and whether these associations were mediated by differences in secondhand smoke in the home, sleep problems, adiposity, and inflammation. We used cross-sectional data collected from 1251 schoolchildren (8-12 years old) in the Tyrol region of Austria and Italy. Information on sociodemographics, lifestyle, perinatal data, and housing conditions was obtained by questionnaire. Behavior problems in the past school year were rated by teachers using the Needleman questionnaire for classroom performance. We estimated nature exposure using a comprehensive naturalness index called "distance to nature" (D2N). This was calculated in several buffer sizes around the child's home and school. Presence of a home garden was assessed by self-report. Data on potential mediators including parental smoking in the home, child's urinary cotinine concentrations, sleep problems, body mass index, and urinary neopterin concentrations were also collected. Structural equation modeling was used to examine the multiple pathways between nature exposure and behavior problems. Children who lived in a home with a garden and those whose school was closer to nature exhibited less school behavior problems. The effect of proximity to nature from the school was directly associated with less behavior problems, and the effect of a home garden on behavior problems acted indirectly through a lower likelihood of secondhand smoke exposure. Associations were in unexpected directions between behavior problems and residential proximity to nature and depended on the outcome and context. Natural environments in school and home surroundings might be beneficial for school conduct and performance. Lower secondhand smoke exposure at home might be a pathway between home gardens and children's behavioral problems. Associations with residential proximity to nature in this study were in unexpected directions and warrant further investigation. These findings serve as a point of departure for investigating how proximal nature might activate health supportive pathways in children and simultaneously confer childhood health benefits via positive behavioral changes in their parents.

Optimum Urine Cotinine and NNAL Levels to Distinguish Smokers from Non-Smokers by the Changes in Tobacco Control Policy in Korea from 2008 to 2018.

We examined the age- and sex-specific distributions of biomarkers of tobacco smoke exposure to determine the optimal cutoffs to distinguish smokers from non-smokers over the last 10 years in Korea, during which smoking prevalence and secondhand smoke (SHS) exposure declined due to changes in tobacco control policy. We analyzed data from the Korea National Health and Nutrition Examination Survey on creatinine-adjusted urinary cotinine (2008-2018; 33 429 adults: 15 653 males and 17 776 females) and 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanol (NNAL; 2016-2018; 6337 adults: 3091 males and 3246 females). We determined the optimal cutoffs and confidence intervals (CIs) to distinguish smokers from non-smokers using receiver operator characteristic curve analysis and bootstrapping (1000 resamples). The optimal cutoff values of creatinine-adjusted urine cotinine and NNAL concentration were 20.9 ng/mg (95% CI: 20.8-21.0, sensitivity: 96.6%, specificity: 93.8%) and 8.9 pg/mg (95% CI: 8.8-8.9, sensitivity: 94.0%, specificity: 94.7%), respectively, in 2016-2018. The optimal cutoffs of both biomarkers increased with age and were higher in females than in males for NNAL concentration. In both sexes, the optimal cutoff of urine cotinine continuously declined over the study period. The optimal cotinine cutoff declined along with smoking prevalence and levels of SHS exposure due to enforcement of tobacco control policies, including smoke-free ordinances and tax increases. Monitoring of biomarkers of tobacco exposure appears necessary for verification of smoking status and regulatory use. Our results based on nationally representative data suggest that a large decrease in the optimal cutoff value of urine cotinine to distinguish smokers from non-smokers was caused by decreases in smoking prevalence and SHS exposure following enforcement of tobacco control policies over the last 10 years. We determined the optimal cutoff values of urine 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanol (NNAL), which were not previously reported in representative population in Asia, to enable more accurate estimation of exposure to tobacco smoke and proper assessment of disease risks. Gender- and age-specific differences in the optimal cutoffs require further study. Monitoring of biomarkers of tobacco smoke exposure seems necessary for verification of smoking status and regulatory use.

Association between Fathers' Use of Heated Tobacco Products and Urinary Cotinine Concentrations in Their Spouses and Children.

Heated tobacco products (HTPs) have become increasingly popular among smokers, especially among young adults in Japan in recent years. Assessments of secondhand tobacco smoke (SHS) exposure due to HTPs are scarce. The present study aimed to assess the urinary levels of total nicotine metabolites (TNMs) of non-smoking spouses and their children following SHS exposure due to their fathers’ use of HTPs. A total of 41 families including 129 participants were recruited between 2018 and 2021. The number of non-smoking spouses and children of the fathers who smoke combustion cigarettes, the fathers who use HTPs, and the fathers who are non-users or have never smoked was 27, 66, and 36, respectively. The urinary levels of TNMs, including cotinine (Cot) and 3′-hydroxycotinine (3-OHCot), were measured using liquid chromatography/tandem mass spectrometry (LC/MS/MS). The spouses and children of fathers who use HTPs had significantly higher levels of TNMs in their urine compared to those with fathers who were non-smokers or non-users. The current study is the first to assess SHS exposure due to HTP use, and to suggest the importance of strategies to prevent exposure to SHS from HTP use in public places and educational strategies to protect non-smokers from secondhand HTP aerosol exposure in households and other private places.

Secondhand Tobacco Smoke and Functional Impairments in Older Adults Living in the Community.

There has been no comprehensive examination of the potential association of SHS with broad functional limitation assessment in older adults, where functional limitations are burdensome and challenging. We examined 2258 community-dwelling non-smoking older adults from the Seniors-Enrica-2-cohort. At baseline (2017) and follow-up (2019) grip strength was measured with a Jamar dynamometer, lower-extremity performance with the Short Physical Performance Battery (SPPB), overall physical function using the physical component summary (PCS) of the Spanish version of the SF-12, frailty with a Deficits Accumulation Index (DAI), and mobility limitations with the Rosow-Breslau scale. Baseline exposure to SHS was assessed by serum cotinine, and past exposure was self-reported. Cross-sectional analyses were performed using linear and logistic regression models, whereas functional performance changes were examined using repeated measures models with robust SE estimates. Overall, the median (IQR) serum cotinine concentration was 0.079 (0.035-0.175) ng/ml, with 20 participants presenting concentrations ≥3 ng/ml. Compared to the unexposed, fully-adjusted models showed that the highest exposure group (≥0.239 ng/ml) presented lower grip strength (mean difference: -1.05 kg; 95% CI = -1.80, -0.31) and higher DAI scores (1.52; 95% CI = 0.38, 2.66) at baseline. Similarly, in models of self-reported past exposure, never-smokers who had lived with ≥2 smokers or been exposed to higher SHS cumulative doses showed lower baseline SPPB values, higher DAI scores, and higher prevalence of mobility limitations. In prospective analyses, those in the highest quartile of baseline cotinine presented harmful SPPB [-0.24 (-0.46, -0.02)] and DAI [1.28 (0.00, 2.55)] changes, and higher risk of mobility limitations [hazard ratio: 1.64; 95% CI = 1.01, 2.68] than the unexposed. SHS exposure over the life-course and during old age may accelerate functional decline. This manuscript provides a comprehensive examination of the relationship between secondhand smoke exposure and a broad range of functional limitations in older adults. Results show that: (i) non-smokers who had been exposed to higher cumulative doses of SHS in adulthood show worse physical function than non-exposed. (ii) Exposure to SHS during old age, as measured with cotinine concentrations, is associated with accelerated short-term functional declines. (iii) The effects of SHS are stronger among older adults with chronic morbidities. (iv) Results suggest that more efforts are needed to protect older adults from passive smoking, especially to those with chronic conditions because of their potential greater vulnerability to the effects of SHS.

Misleading qualification of active smokers based on carbon monoxide measurement of exhaled air

Abstract Funding Acknowledgements Type of funding sources: Public Institution(s). Main funding source(s): Centre of Postgraduate Medical Education Background Carbon monoxide (CO) concentration of exhaled air is widely used in clinical trials in assessment of active smoking due to its feasibility and cost-effectiveness. The concentration of nicotine metabolite cotinine in urine is used as an objective index of smoking. Purpose We aimed to compare self-reported smoking and smoking cessation (SC) with results of CO and cotinine concentration. Methods Patients after coronary angiography (n=62) were included in SC programme with a brief counselling. The self-reported smoking and SC was verified with urine cotinine assessment (NicAlert) and CO level in exhaled air (MicroCO). The criterium of SC was non-smoking (&amp;lt;1 cigarette ) in the last 7 days, NicAlert ≤2, MicroCO test≤6 parts per million (ppm). Results The mean age of patients was 61 ± 7.7 years, 49 (79%) patients were men, with median load of smoking 10 pack-years. 40 patients were assessed with both methods at baseline and follow-up visit. At baseline all the patients declaring at least 10 cigarettes daily had Nic Alert 6, but MicroCO indicated non-smoking in 25 (62,5%) patients. At follow up visit after 1 month, 35 (56,5%) patients declared SC and there was numerically higher level of misleading results of CO concentration in the whole group (p=0.077) and significantly higher in the group of patients who self-reported continuation of smoking (p=0.009)(Table 1). Conclusion Despite widespread and cost-effective measurement of CO the result should be carefully interpreted. It accurately indicates non-smoking patients, but the measurement in active smokers might be misleading with a significant group of patients with false negative results. To accurately assess active smokers the CO measurement should be supported with other method such as measurement of cotinine levels.

Geometric Mean Serum Cotinine Concentrations Confirm a Continued Decline in Secondhand Smoke Exposure among U.S. Nonsmokers-NHANES 2003 to 2018.

The objective of this study was to examine long-term trends in serum cotinine (COT) concentrations, as a measure of secondhand smoke (SHS) exposure, in U.S. nonsmokers using data from the National Health and Nutrition Examination Surveys (NHANES) from 2003 to 2018. We analyzed NHANES serum COT results from 8 continuous NHANES 2 year cycles from 2003 to 2018 using a liquid chromatography–tandem mass spectrometry assay that has been maintained continuously at the Centers for Disease Control and Prevention (CDC) since 1992. Serum COT concentrations (based on the geometric means) among nonsmokers in the U.S. decreased by an average of 11.0% (95% confidence interval (CI) [8.8%, 13.1%]; p < 0.0001) every 2 year cycle. From 2003 to 2018, serum COT concentrations in U.S. nonsmokers declined by 55.0%, from 0.065 ng/mL in 2003–2004 to 0.029 ng/mL in 2017–2018 (p < 0.0001). Significant decreases in serum COT concentrations were observed in all demographic groups. While disparities between these groups seems to be shrinking over time, several previously observed disparities in SHS exposure remain in 2017–2018. Serum COT concentrations of the non-Hispanic Black population remained higher than those of non-Hispanic Whites and Mexican Americans (p < 0.0001). Additionally, serum COT concentrations were significantly higher for children aged 3–5 years than other age groups (p ≤ 0.0002), and men continued to have significantly higher serum COT concentrations than women (p = 0.0384). While there is no safe level of exposure to SHS, the decrease in serum COT concentrations in the U.S. population as well as across demographic groupings represents a positive public health outcome and supports the importance of comprehensive smoke-free laws and policies for workplaces, public places, homes, and vehicles to protect nonsmokers from SHS exposure.

Impact of Secondhand smoking on Dyslipidaemia among non-smokers: findings from the 2015-2016 NHANES dataset in the United States

Abstract Funding Acknowledgements Type of funding sources: Public grant(s) – National budget only. Main funding source(s): This research was supported by the Brain Pool Program supported through the National Research Foundation of Korea, funded by the Ministry of Science and ICT (2020H1D3A1A04081265). Background Dyslipidemia is a prominent risk factor of mortality globally. While active smoking has been implicated in the burden of cardiovascular disease (CVD) worldwide, there is little understanding on the impact of subtle secondhand smoke exposure (SHSE) on dyslipidaemia among non-smokers. Purpose This study assessed the association of SHSE with dyslipidaemia among non-smoking adults from the 2015-2016 National Health and Nutrition Examination Survey (NHANES) in the United States. Method Participants for this study were 3,064 non-smoking adults (≥18years) identified through a multistage sampling method in the United States. Data on sociodemographic, lifestyle and history of CVD were collected using standard operating principles. Also, fasting blood samples were collected by trained personnel to determine blood lipid profiles. SHSE was defined as exposure to smoke from a burning cigarette (exhaled by a smoker) in an indoor environment or a blood cotinine concentration ≥ 0.05 ng/ml. Dyslipidemia was defined according to the National Cholesterol Education Program guidelines. Logistic regression was adopted to estimate the multivariable-adjusted odds ratio (aOR) and 95% confidence interval (CI) for the association between SHSE and dyslipidaemia at a two-sided P &amp;lt; 0.05. Results The mean age of respondents was 46.4 ± 18.0years, 63.2% were females, 36.2% reported SHSE, and 59.6% had dyslipidemia. The aOR and 95% CI among respondents with SHSE was 1.148 (1.147-1.149) in the entire sample. Similarly, odds of dyslipidaemia in the light of SHSE was 1.130 (1.129-1.131) among those &amp;lt; 60 years, 1.304 (1.300-1.308)] among those ≥ 60 years, 1.165 (1.163-1.167) among males and 1.214 (1.212-1.215) among females. Conclusion(s) SHSE was associated with higher odds of dyslipidaemia and might be an often missed risk factor in the risk of dyslipidaemia. Primary prevention strategies(s) might be necessary to reduce the impact of SHSE on the burden of dyslipidaemia and CVD worldwide.

Prenatal E‐Cigarette Use Disrupts Blood‐Brain Barrier (BBB) Integrity and Induces Pro‐Inflammatory Cytokines in Postnatal Brain

PurposeElectronic cigarette (e‐Cig) is often considered as a safer alternative to smoking for pregnant women however, its potential toxic effect on neonatal health warrants further investigation. Toxic effects of prenatal tobacco smoking on postnatal health have been reported in several studies however, regarding thorough investigation of e‐Cig exposure during pregnancy is currently unavailable. Due to the staggering growth in e‐Cig usage among pregnant women (10%), it has become critical to explore the consequences of maternal e‐cig use on postnatal health outcomes. Hence, in this study, we have evaluated the consequences of prenatal e‐Cig use during pregnancy on postnatal blood‐brain barrier (BBB) integrity, proinflammatory cytokine levels and behavioral outcomes in offspring.MethodPregnant CD1 mice (E5) were exposed to e‐Cig vapor (2.4% nicotine) till postnatal day (PD) 7. Weight of the offspring was measured up to PD 90. Nicotine and cotinine concentration in plasma and brain were measured in PD 7 offspring by LC‐MS/MS. The expression level of structural elements of the BBB including, tight junction proteins (ZO‐1, claudin‐5, occludin), astrocyte (GFAP), pericyte (PDGFRβ) and basement membrane (Laminin α1, Laminin α4) were analyzed in offspring using western blot and immunohistochemistry at PD 7, PD 23, PD 45 and PD 90. The expression level of pro‐inflammatory cytokines (IL‐1α, IL‐1β, IL‐2, IL‐4, IL‐5, IL‐6, IL‐7, IL‐10, IL‐12, IL‐17α, KC, LIX, MIP‐2 and TNF‐α) in brain were measured at PD 7 and PD 90. To evaluate behavioral outcomes, open field test, novel object recognition test and morris water maze test were performed on adolescent and adult offspring.ResultsReduced body weight was observed in e‐Cig exposed offspring at all time points till PD 90 compared to control (P &lt;0.05). Plasma concentration of nicotine and cotinine in PD 7 offspring was 3.215 ng/mL and 3.373 ng/mL respectively whereas in brain, these two concentrations were 43.72 ng/mL and 1.123 ng/mL respectively. Significantly reduced expression of brain tight junction proteins and GFAP were observed in male and female offspring at PD 7, PD 23, PD 45 and PD 90 (P &lt;0.05). Moreover, higher level of brain IL‐1α, IL‐6, IL‐7, IL‐10, IL‐17α, KC and TNF‐α was found in prenatally e‐cig exposed offspring at PD 7. However, only IL‐6 and IL‐17α were observed at higher levels in brain for prenatally e‐cig exposed adult offspring at PD 90 (P &lt;0.05). Additionally, disrupted motor, learning and memory function were observed in prenatally e‐Cig exposed adolescent and adult offspring.ConclusionOur findings suggest that prenatal e‐Cig exposure induces potential neurotoxic effects on neonates by disrupting postnatal blood‐brain barrier integrity and inducing proinflammatory brain cytokines which may result in alteration in neurological, cerebrovascular, and behavioral outcomes.

Abstract 547: Chronic Nicotine Exposure Affects Induced Pluripotent Stem Cell-derived Endothelial Cell Therapy In A Murine Model Of Peripheral Artery Disease

Treatment strategies for peripheral artery disease (PAD) remain limited due to the many challenges of surgical intervention. Stem cell therapy offer a promising option, but barriers exist to their clinical translatability. Among these barriers include lifestyle choices like nicotine use that may influence the efficacy of stem cell therapy. The objective of this study aims to examine the efficacy of iPSC-EC therapy for treatment of PAD in mice with prior chronic exposure to nicotine. We hypothesize that chronic nicotine exposure negatively affects the therapeutic potential of implanted iPSC-ECs in a murine model of PAD. NSG mice were implanted with an osmotic pump for controlled exposed to nicotine or saline (control) for 28 days. Plasma cotinine was measured to confirm nicotine exposure. After 28 days of nicotine or saline exposure, the mice underwent induction of hindlimb ischemia and before receiving an injection of 10 6 iPSC-ECs. A second dose of cells were injected to the ischemic limb on day 7 post-surgery. All mice were monitored for blood perfusion recovery using laser Doppler spectroscopy imaging. Survival of the transplanted cells in vivo were tracked by bioluminescence imaging. The mice receiving iPSC-ECs were also imaged for cell survival using bioluminescence imaging. At day 14 post-surgery, mice were euthanized, and the gastrocnemius muscle and thigh muscle were harvested for histological analysis. The results show that the average cotinine concentration in sera was ~200 ng/mL, which is within physiological range for a tobacco user. Blood perfusion recovery at day 14 showed trends of nicotine treated groups have hindered perfusion recovery, compared to those treated with saline. Importantly, nicotine exposure trended with poorer perfusion recovery after cell therapy. Bioluminescent imaging showed iPSC-ECs persisted in vivo for all groups with a gradual decline in cell numbers over time. In conclusion, nicotine exposure was associated with poorer blood perfusion recovery after iPSC-EC therapy, compared to control saline exposure, suggesting that chronic nicotine exposure may have adverse effects on the efficacy of iPSC-EC therapy for treatment of PAD.

Validation of a high-throughput method for simultaneous determination of areca nut and tobacco biomarkers in hair using microwave-assisted extraction and isotope dilution liquid chromatography tandem mass spectrometry

For people with habits of chewing betel nuts and smoking, the probability of suffering from oral cancer is ten to a hundred times higher than others. Due to the serious health consequences of areca nut and tobacco, a reliable cessation program is needed. Hair is the best option to document long-term exposure. Unfortunately, the research on betel nut in hair did not attract much attention. In this study, a high-throughput method based on microwave-assisted extraction (MAE) and isotope dilution liquid chromatography tandem mass spectrometry (LC-MS/MS) was developed to measure the four biomarkers of betel nuts and cigarettes, including areca alkaloids (arecoline), tobacco alkaloids (nicotine), and their metabolites (arecaidine and cotinine). The hair sample was washed, cut, weighed, and incubated for 3 min MAE with methanol/trifluoroacetic acid, then evaporated and reconstituted for LC-MS/MS analysis. The total experiment time was 50 min. The lower limits of quantification (LOQ) were 5–10 pg/mg. The intra-day and inter-day precision were 2.2–7.6%. Intra-day and inter-day accuracy were − 6.1–8.2%. The method showed good linearity (r2 > 0.995) over LOQ - 1000 pg/mg concentration ranges. It was successfully applied to analyze 11 subjects of regular areca nut chewers, also smokers. Eight samples were black hair; three samples were naturally black hair with partially gray hair. Measured concentrations in black hair were in the range 56.9 pg/mg to 3.2 ng/mg for arecoline, 12.8 pg/mg to 222.2 pg/mg for arecaidine, 3.8 ng/mg to 33.4 ng/mg for nicotine and 1.1 ng/mg to 6.1 ng/mg for cotinine. The results showed lower levels in gray hair. This method was utilized successfully to analyze pg/mg levels of arecoline, arecaidine, nicotine, and cotinine, and good recoveries were obtained. The mean concentration of arecaidine and cotinine in hair was 15% and 20% of arecoline and nicotine, respectively. A good positive correlation was found between the concentrations of these compounds and self-report. This method improved extraction speed, concentration, and analysis of samples and is useful for monitoring betel nut and smoking cessation programs.