Association between serum cotinine and total testosterone in adult males based on NHANES 2011-2016.

The relationship between smoking and testosterone levels in adult males remains a topic of ongoing debate. Serum cotinine is considered a reliable marker of both smoking intensity and exposure to tobacco smoke. Therefore, we aim to examine the association between serum cotinine levels and total testosterone concentrations in adult males using data from the U.S. National Health and Nutrition Examination Survey (NHANES) database. Our study assessed the relationship between serum cotinine and total testosterone using weighted linear regression models and subgroup analysis. A fully adjusted model with smooth curve fitting was employed to investigate the potential nonlinear association between serum cotinine and total testosterone. Threshold effects were analyzed to identify the inflection point between serum cotinine and total testosterone. Indeed, a total of 7797 participants were included in our study. After adjusting for potential confounding variables, the findings indicate a positive association between serum cotinine levels and total testosterone levels (ß: 0.05, 95%CI: 0.02, 0.09). Furthermore, applying smoothed curve fitting analysis and threshold effects, an inflection point was detected at a serum cotinine level of 487 ng/ml. Above this threshold, total testosterone levels declined with increasing serum cotinine levels. In conclusion, the findings of our study suggest a positive association between elevated serum cotinine levels and total testosterone levels in adult men. However, it is essential to note that this association may be reversed at excessively high serum cotinine concentrations.

Effect of polyunsaturated fatty acids intake on the occurrence of current asthma among children and adolescents exposed to tobacco smoke: NHANES 2007-2018.

BACKGROUND: Asthma is an airway inflammatory disease driven by multiple factors with a high incidence in children and adolescents. Environmental tobacco smoke exposure (TSE) and diet are inducing factors for asthma. The potential of omega-3 polyunsaturated fatty acids (PUFAs) to alleviate asthma symptoms by their anti-inflammatory effects has been explored. However, to date, no studies have explored the effect of dietary PUFAs intake on the asthma in children and adolescents exposed to tobacco smoke. OBJECTIVE: We aimed to examine the effect of dietary PUFAs intake on the current asthma in children and adolescents exposed to tobacco smoke. METHODS: Data of this cross-sectional were extracted from the National Health and Nutrition Examination Survey (NHANES) 2007-2018. Children and adolescents with serum cotinine concentration ≥ 0.05 ng/mL were defined to exposed to tobacco smoke. Dietary PUFAs intake information were obtained from 24 h recall interview. The weighted univariate and multivariate were utilized to explore the effect of PUFAs on the association of asthma and TSE, with adjusted odds ratios (AORs) and 95% confidence intervals (CIs). These moderating effects were further explored based on the age, gender and body mass index (BMI) and sedentary time. RESULTS: Totally, 7981 eligible children and adolescents were included, with the mean age of 11.96 ± 0.06 years old. Of whom, 1.024 (12.83%) had current asthma. After adjusted all covariates, we found children and adolescents with TSE had high occurrence of current asthma (AOR = 1.2, 95% CI 1.03-1.63); We also found omega-3 PUFAs intake (P for interaction = 0.010), not omega-6 PUFAs (P for interaction = 0.546), has a moderating effect on the association of TSE and current asthma. Moreover, we further observed that children and adolescents with TSE and low omega-3 PUFAs intake had high occurrence of current asthma (AOR = 1.58, 95% CI 1.19-2.10), while no significant association was found in children and adolescents with high omega-3 PUFAs intake (all P > 0.05). This moderating effect was more prominent in children and adolescents aged ≤ 12 years old (AOR = 1.62, 95% CI 1.06-2.47), girls (AOR = 2.14, 95% CI 1.15-3.98), overweight (AOR = 1.87, 95% CI 1.01-3.47) and sedentary time > 6 h (AOR = 1.96, 95% CI 1.00-3.86). CONCLUSION: We found dietary omega-3 PUFAs plays a moderating effect on the association of asthma and TSE in children and adolescents, especially in children and adolescents aged ≤ 12 years, girls, overweight or sedentary time > 6 h. This moderating effect suggested higher omega-3 intake has potential benefits in decreasing the occurrence of asthma in children and adolescents who exposed to tobacco smoke.

Cotinine exposure enhances the association of blood manganese and non-alcoholic fatty liver disease in American children: a cross-sectional study.

This cross-sectional survey aims to determine whether cotinine exposure would enhance the relationship between blood manganese (Mn) and non-alcoholic fatty liver disease (NAFLD) in children using the NHANES database. Restricted cubic spline (RCS) and logistic regression analyses were adopted to determine the potential relationship. Besides, we tested the robustness of the results by performing trend tests and subgroup analyses. The study finally enrolled 866 children aged 18 years and below. Blood Mn was linearly linked to NAFLD and the risk of NAFLD was increased with the blood Mn elevation (P < 0.05). There was a notable relationship between blood Mn and NAFLD in crude model 1, which was still significant upon adjustment of all the identified covariates (all P < 0.05). Under Mn exposure, the cotinine-exposed group had a higher risk of NAFLD than the cotinine-unexposed group. In conclusion, blood Mn level is an independent risk factor for pediatric NAFLD, and cotinine exposure can enhance this relationship to some degree. Therefore, reducing cotinine exposure may alleviate detrimental consequences related to exposure to heavy metals in children.

Urine levels of nicotine and its metabolites in young population exposed to second-hand smoke in nightclubs: a pilot study.

The aim of this study was to investigate the extent of second-hand smoke exposure in younger population visiting nightclubs in Croatia by comparing the levels of nicotine and its main metabolites cotinine and trans-3'-hydroxycotinine (3HC) in urine samples taken from 22 participants before and after spending about three hours in a nightclub, stratified by smoking status (smokers and non-smokers). The samples were prepared by liquid-liquid extraction and analysed with gas chromatography-mass spectrometry. The presence of nicotine, cotinine, and 3HC was confirmed in all urine samples. Their median concentrations significantly differed between the two measurements in non-smokers. Our findings show that even a three-hour exposure to second-hand smoke can significantly increase the levels of nicotine and its metabolites in urine, which are indicative of exposure to other, harmful tobacco smoke substances. They also call for raising awareness of the health risks of exposure to second-hand smoke in the general population and among individuals who frequent nightclubs in particular.

Association of magnesium deficiency, tobacco smoke exposure and hypertension in children and adolescents: evidence from the NHANES 2007-2018.

BACKGROUND: Recent studies suggested that the combination of tobacco smoke exposure (TSE) and dietary nutrients intake may be related to a higher or lower risk of hypertension. However, the relationship between dietary magnesium (Mg) intake, TSE and the odds of hypertension remain unclear. This study aimed to evaluate the association of TSE, dietary Mg intake and the odds of hypertension among children and adolescents. METHOD: Data of this study were extracted from the National Health and Nutrition Examination Surveys (NHANES) 2007-2018. Dietary Mg intake was calculated as the average of two days of dietary and supplementations intake. Serum cotinine concertation ≥ 0.05 µg/L or at least one-person smoking in the household was considered as exposing to the tobacco smoke. The weighted univariate and multivariate logistic regression models were utilized to explore the associations of dietary Mg intake, TSE and the odds of hypertension among children and adolescents with the evaluation index of odds ratio (ORs) and 95% confidence intervals (CIs). Subgroup analyses based on different age, gender and overweight were further assessed these associations. RESULTS: A total of 7,122 children and adolescents aged 8-17 years old and with the blood pressure measurement were included. Of which, 948 (13.31%) had hypertension. After adjusting all covariates, we observed children and adolescents exposed to tobacco smoke was related to higher odds of hypertension (OR = 1.34, 95%CI: 1.01-1.78); children and adolescents not reached the dietary Mg references intakes was related to higher odds of hypertension (OR = 1.48, (95%CI: 1.11-1.97); compared to children and adolescents non-TSE and reached the DRIs of Mg, those not reached the DRIs of Mg and exposed to tobacco smoke have the highest odds of hypertension (OR = 1.94, 95%CI: 1.30-2.89, P for trend = 0.002). These associations of dietary Mg intake, TSE and hypertension remain robust after the stratified analysis based on age, gender and overweight was conducted. CONCLUSION: Our findings suggested there were a robust association between dietary Mg intake, TSE and hypertension in children and adolescents. Those children and adolescents with deficiency dietary Mg intake and exposed to tobacco smoke may have the high odds of hypertension. More restrictions on smoking as well as Mg supplementation in the prevention and treatment of hypertension among children and adolescents might be justified.

Epigenetic Biomarker: Improving Estimates of Fetal Exposure to Cigarette Smoke.

The well-known cotinine test captures recent smoking, and survey responses are not always accurate. Now researchers propose a measure of DNA methylation in placental tissue that may be better than either.

Differential effects of environmental exposures on clinically relevant endophenotypes between sexes.

Sex and gender differences play a crucial role in health and disease outcomes. This study used data from the National Health and Nutrition Examination Survey to explore how environmental exposures affect health-related traits differently in males and females. We utilized a sex-stratified phenomic environment-wide association study (PheEWAS), which allowed the identification of associations across a wide range of phenotypes and environmental exposures. We examined associations between 272 environmental exposures, including smoking-related exposures such as cotinine levels and smoking habits, and 58 clinically relevant blood phenotypes, such as serum albumin and homocysteine levels. Our analysis identified 119 sex-specific associations. For example, smoking-related exposures had a stronger impact on increasing homocysteine, hemoglobin, and hematocrit levels in females while reducing serum albumin and bilirubin levels and increasing c-reactive protein levels more significantly in males. These findings suggest mechanisms by which smoking exposure may pose higher cardiovascular risks and greater induced hypoxia for women, and greater inflammatory and immune responses in men. The results highlight the importance of considering sex differences in biomedical research. Understanding these differences can help develop more personalized and effective health interventions and improve clinical outcomes for both men and women.

Modeling the Effects of Policies that Restrict Tobacco Retail Outlets on Prenatal Smoke Exposure and Perinatal Health Care Utilization.

Tobacco retail outlet (TRO) density has been associated with increased cotinine levels in pregnant persons and their children. As such, the higher densities of TROs may represent higher levels of active smoking during pregnancy. The purpose of this study is to simulate the reduction in cotinine (a biomarker of smoke exposure) and health care utilization that could occur in pregnant persons under enactment of several candidate TRO reduction policy recommendations. Using existing retail outlet data from the state of North Carolina and from the Newborn Epigenetic Study (NEST), the present study created hypothetical policy-informed datasets of TROs that a) limited the number of TROs to the same density as the 2014 San Francisco (SF) policy (Policy 1), b) set the minimum distance to 500 feet between TROs from a school and from other TROs (Policy 2), c) restricted the types of TROs to exclude pharmacies (Policy 3), and d) a combination of Policies 1-3 (Policy 4). We estimated the effects of each policy individually and in a separate model with their combined effects in terms of the reduction on cotinine levels and health care utilization, as measured by number of visits to the emergency department (ED). We found that the hypothetical policies were likely to be effective in reducing maternal cotinine and ED visits, with the majority of the mothers in the dataset demonstrating reductions in these outcomes after implementation of the policies. We found that Policy 1 led to moderate reductions in TRO exposure for the majority of the sample as well as stratified by race/ethnicity. Additionally, Policy 4 had slightly larger estimated effects than Policy 1, but could be more onerous to implement in practice. Overall, we identified evidence supporting the efficacy of TRO reduction strategies that could impact smoke exposure during pregnancy in our diverse sample in North Carolina.

Serum cotinine levels and adolescents' sleep health outcomes from NHANES 2005 to 2018.

The association between tobacco smoke exposure and sleep has been widely discussed, but the correlation between serum cotinine levels and sleep health outcomes in adolescents has not been well described. This study aimed to further evaluate the association between serum cotinine levels and sleep health outcomes in adolescents using data from the National Health and Nutrition Examination Survey (NHANES) from 2005 to 2018. This cross-sectional study included participants aged 16-19 years from the NHANES 2005-2018. A weighted multivariate logistic regression model was used for the primary analysis. A restricted cubic spline (RCS) model was employed to investigate the non-linear association between serum cotinine levels and trouble sleeping. Subgroup analyses based on population characteristics were also conducted. In total, 2630 participants were included, which are representative of the 11.5 million US adolescents. Higher serum cotinine levels (≥ 3 ng/ml) were significantly associated with trouble sleeping in the fully adjusted model (odds ratio [OR] 1.817). The RCS model revealed a non-linear relationship between serum cotinine levels and trouble sleeping. Subgroup analyses indicated that this relationship was consistent and stable across various population characteristics. Serum cotinine levels are associated with sleep health outcomes in adolescents, with high serum cotinine levels being linked to increased trouble sleeping and longer or shorter sleep duration.

Simultaneous Determination of Tobacco Smoke Exposure and Stress Biomarkers in Saliva Using In-Tube SPME and LC-MS/MS for the Analysis of the Association between Passive Smoking and Stress.

Passive smoking from environmental tobacco smoke not only increases the risk of lung cancer and cardiovascular disease but may also be a stressor triggering neuropsychiatric and other disorders. To prevent these diseases, understanding the relationship between passive smoking and stress is vital. In this study, we developed a simple and sensitive method to simultaneously measure nicotine (Nic) and cotinine (Cot) as tobacco smoke exposure biomarkers, and cortisol (CRT), serotonin (5-HT), melatonin (MEL), dopamine (DA), and oxytocin (OXT) as stress-related biomarkers. These were extracted and concentrated from saliva by in-tube solid-phase microextraction (IT-SPME) using a Supel-Q PLOT capillary as the extraction device, then separated and detected within 6 min by liquid chromatography-tandem mass spectrometry (LC-MS/MS) using a Kinetex Biphenyl column (Phenomenex Inc., Torrance, CA, USA). Limits of detection (S/N = 3) for Nic, Cot, CRT, 5-HT, MEL, DA, and OXT were 0.22, 0.12, 0.78, 0.39, 0.45, 1.4, and 3.7 pg mL-1, respectively, with linearity of calibration curves in the range of 0.01-25 ng mL-1 using stable isotope-labeled internal standards. Intra- and inter-day reproducibilities were under 7.9% and 14.6% (n = 5) relative standard deviations, and compound recoveries in spiked saliva samples ranged from 82.1 to 106.6%. In thirty nonsmokers, Nic contents positively correlated with CRT contents (R2 = 0.5264, n = 30), while no significant correlation was found with other biomarkers. The standard deviation of intervals between normal beats as the standard measure of heart rate variability analysis negatively correlated with CRT contents (R2 = 0.5041, n = 30). After passive smoke exposure, Nic levels transiently increased, Cot and CRT levels rose over time, and 5-HT, DA, and OXT levels decreased. These results indicate tobacco smoke exposure acts as a stressor in nonsmokers.

Shisha Consumption and Presence of Cotinine in Saliva Samples among Students in Public Universities in Coastal Kenya.

Background: Despite the well-known adverse health effects of tobacco, shisha use among students in tertiary institutions remains a public health concern. In Kenya, the literature on status of shisha after the 2017 ban is scanty. This study sought to ascertain actual shisha use among university students along the coastal strip. Methods: We investigated confirmed and self-reported shisha use. Using proportionate-to-size and snowball sampling methods, 380 respondents were enrolled from three universities. Sociodemographic characteristics and self-reported history of shisha use were documented using a participant-assisted questionnaire. Actual shisha use was determined qualitatively using 6 panel plus alcohol saliva test kit that detected cotinine use among other selected drugs. Results: Of the 380 participants, 278 (73%) were males and their median (IQR) age was 22 (20-23) years. This study reports 29% current use based on testing positive for cotinine. Among those who reported current ever use of shisha, 19% tested positive for cotinine, respectively. In the multivariable analysis, being separated (adjusted risk ratio (aRR): 2.06 (95% CI: 1.45-2.94)) compared to being single and studying for a degree compared to a diploma (aRR: 1.32 (95% CI: 1.10-1.58)) were associated with cotinine positive. The 4th year of study (aRR: 1.68 (95% CI: 1.22-2.33)) compared to the 1st year and reported knowledge of shisha (aRR: 1.84 (95% CI: 1.18-2.87)) were associated with cotinine positive. Conclusion: Nearly one-third of university students along the Kenyan coast are active shisha users. Saliva testing for cotinine is a more reliable method of reporting tobacco use. We recommend upscaling of health education, re-enforcement of the current ban on shisha consumption by concerned authorities, and saliva testing for cotinine while assessing current tobacco use.

Cotinine influences the effect of high and low nicotine concentrations on planarian motility differently.

Previous work from our laboratory showed that cotinine, a nicotine metabolite, reverses three nicotine-induced behavioral effects in freshwater planarians: motility decrease, seizure-like movements, and withdrawal-like behaviors. The present work explored whether cotinine, a nicotine metabolite, antagonized the nicotine-induced effects on planarian motility in a concentration-dependent manner. We found that nicotine decreased planarian motility at nicotine concentrations above 60 µM but increased planarian velocity at concentrations equal to or below 50 µM, in agreement with previous data. Cotinine did not affect planarian motility at a concentration range between 250 and 2750 µM. Furthermore, we found that cotinine alleviated the 100 µM nicotine-induced motility decrease in a concentration-dependent manner and reversed the low nicotine concentration motility increase, albeit in a concentration-independent manner. The apparent concentration-dependent alleviation of >60 µM nicotine-induced motility decrease by cotinine suggests an orthosteric relationship between nicotine and cotinine. On the other hand, the evident concentration-independent cotinine alleviation of the increase in motility induced by 50 µM nicotine suggests an allosteric relationship. Our data is consistent with the existing literature about the relationship between nicotine and cotinine in various models, reinforcing the case for the usefulness of the planarian model in pharmacological studies.

Determination of Cotinine, 3'-Hydroxycotinine and Nicotine 1'-Oxide in Urine of Passive and Active Young Smokers by LC-Orbitrap-MS/MS Technique.

Tobacco smoke is probably the most significant factor conducing to toxic xenobiotics exposure to humans. The aim of the study was to develop a rapid and sensitive method for the determination of selected nicotine metabolites in urine of tobacco smokers and passive smokers. The method for removing protein and extracting the metabolites involved the centrifugation of urine with acetonitrile. Cotinine, trans-3'-hydroxycotinine, and (2'S)-nicotine 1'-oxide in the supernatant were determined using the LC-Orbitrap-MS/MS technique, with the selected ion monitoring (SIM) and parallel reaction monitoring (PRM) modes used. The recovery of these analytes added to the urine samples ranged from 72% to 101%. Repeatability and reproducibility were less than 3.1% and 10.1%, respectively. The study was carried out among medical students. The group was selected as representatives of young people and who as future physicians should be more aware of the effects of nicotine use. Concentration levels of cotinine and trans-3'-hydroxycotinine determined in ng/mL in the urine of cigarette smokers were 70- and 58-fold higher, respectively, compared to passive smokers. Higher concentrations were recorded in the urine of those passively exposed to tobacco smoke than in non-smokers, confirming that passive exposure to tobacco smoke is not harmless to the human body. However, no significant differences were observed in the concentration of (1'S,2'S)-nicotine 1'-oxide in the samples of individuals from various groups.

Patterns of Marijuana Use and Nicotine Exposure in Patients Seeking Elective Aesthetic Procedures.

BACKGROUND: With the increasing legalization and popularity of marijuana, it is frequently and sometimes unintentionally combined with nicotine-containing products. As a consequence, patients may fail to accurately report usage during preoperative examinations or remain unaware of the inclusion of nicotine. This poses a challenge for clinicians in identifying preoperative nicotine exposure. This study aimed to establish normative data on the use of marijuana and nicotine in plastic surgery patients and correlate it with urine nicotine and cotinine levels. METHODS: All consecutive patients presenting to the authors' clinic seeking elective procedures were identified. Patients were surveyed on marijuana and nicotine use, and provided a urine sample for analysis. The survey responses, urine results, surgical treatments, and clinical outcomes were followed up prospectively. RESULTS: A total of 135 patients completed the survey and were categorized as nonusers (50%), active nicotine users (19%), active marijuana users (7%), active users of both (13%), or past users (11%). Marijuana users who denied nicotine use showed significantly elevated nicotine and cotinine levels compared with nonusers (average nicotine level, 23.1 ± 13.5 ng/mL [P = 0.00007]; average cotinine level, 221.2 ± 141.8 ng/mL [P = 0.0002]). Fewer than a third of active marijuana or nicotine users reported active use of these products during clinical encounters. There was no difference in urine levels, reported use, or other patient characteristics in patients with and without postoperative complications. CONCLUSION: This is the first descriptive study to document elevated urine nicotine levels in self-reported marijuana users in an urban, diverse patient population seeking elective plastic surgery procedures.

Association between serum cotinine levels and urinary incontinence in adults in the United States: a population-based cross-sectional analysis.

Environmental tobacco smoke (ETS) exposure has been shown to be associated with a variety of diseases, but evidence regarding the association between it and urinary incontinence (UI) is limited. Cotinine, a metabolite of nicotine in the human body, can more accurately quantify the level of human exposure to tobacco smoke. The study utilized data from seven survey cycles (2007-March 2020 Pre-pandemic) of the National Health and Nutrition Examination Survey (NHANES) program. Weighted multivariable logistic regression analysis, subgroup analysis, interaction tests, smooth curve fitting, and threshold effect models were used to analyze the relationship between serum cotinine and UI. Additionally, a 1:1 nearest neighbor propensity score matching (PSM) method was employed to minimize the impact of confounding factors. Before and after PSM, serum cotinine levels were higher in individuals with UI than those without (P < 0.05). Both before and after PSM, UI was positively correlated with serum cotinine levels, with a significantly increased risk of urinary incontinence when serum cotinine levels were in the Q3 range (before PSM: OR = 1.89, 95% CI = 1.59-2.24; after PSM: OR = 1.60, 95% CI = 1.28-2.00). Smooth curve fitting before and after PSM showed an approximate J-shaped non-linear dose-response relationship between log-transformed serum cotinine levels and UI. This study indicates that among American adults, there is a positive relationship between serum cotinine levels and UI, which is also significant in self-reported non-smoking populations. Therefore, reducing exposure to environmental tobacco smoke (e.g., avoiding second-hand smoke) in work and daily life may help alleviate the occurrence of UI, and serum cotinine levels have the potential to be a tool for predicting the degree of risk of developing UI.

Effect of dietary antioxidant quality score on tobacco smoke exposure and asthma in children and adolescents: a cross-sectional study from the NHANES database.

BACKGROUND: Asthma is a common non-communicable disease in children, and airway inflammation is the main pathological change of asthma. Tobacco smoke exposure (TSE) can cause systematic inflammation and oxidative stress, which may further aggravate the progression of asthma. Dietary antioxidants can relieve the inflammation and oxidative stress in human body. This study aims to assess the effect of overall antioxidant capacity of dietary intake, evaluating by dietary antioxidant quality score (DAQS), in the association between TSE and childhood asthma. METHODS: Data of this cross-sectional study were extracted from the National Health and Nutrition Examination Surveys (NHANES) 2007-2018. DAQS was calculated based on the daily dietary intake of selenium, zinc, magnesium, vitamin A, C and E. TSE was measured by serum cotinine concentration. The weighted univariate and multivariate logistic regression models were employed to evaluate the role of DAQS in the association between TSE and asthma among children and adolescents. Subgroup analysis was conducted to further evaluate the association based on gender. RESULTS: Totally 11,026 children and adolescents were included, of whom 1,244 (11.28%) had asthma. After adjusted all covariates, TSE was associated with the high odds of childhood asthma (OR = 1.26, 95%CI = 1.05-1.52). Among children exposed to tobacco smoke, those with higher DAQS level (OR = 1.15, 95%CI: 0.88-1.50) had a reduced risk of asthma compared with those children with lower DAQS level (OR = 1.43, 1.08-1.89), especially among girls (OR = 1.42, 95%CI: 0.93-2.17). CONCLUSION: High DAQS may have a moderating effect on asthma in children; that is, the higher DAQS, the lower the odds of asthma in children who exposed to tobacco smoke. Our study provides a reference for developing more targeted strategies for prevention and treatment of asthma in children.

Association between serum cotinine and muscle mass: results from NHANES 2011-2018.

PURPOSE: Recently, the detrimental effect of cigarette smoking on muscle metabolism has attracted much attention, but the relationship between cigarette smoking and muscle mass is poorly understood. Thus, this study investigated the association between exposure to cigarette smoke, defined based on serum cotinine, and muscle mass in the US population. METHODS: We utilized National Health and Nutrition Examination Survey (NHANES) data between 2011 and 2018 for analysis. Data on serum cotinine, muscle mass (quantified by appendicular skeletal muscle mass index, ASMI), and covariates were extracted and analyzed. Weighted multivariate linear regression analyses and smooth curve fittings were performed to investigate the association between serum cotinine and ASMI. Subgroup analyses were stratified by gender, race and smoking status. When nonlinearity was detected, the threshold effects were analyzed using a two-piecewise linear regression model. RESULTS: In total, 8004 participants were included for analysis. The serum level of cotinine was negatively associated with ASMI in the fully adjusted model. Furthermore, comparing participants in the highest vs. the lowest tertile of serum cotinine, we found that ASMI decreased by 0.135 Kg/m2. In subgroup analysis stratified by gender and race, the association between serum cotinine and ASMI remained significant in all genders and races. In addition, the association remained significant among current and former smokers, but not among those who never smoked. Smooth curve fittings showed nonlinear relationships between serum cotinine and ASMI, with the inflection points identified at 356 ng/mL. CONCLUSIONS: Our study revealed that serum cotinine was negatively related to muscle mass. This finding improves our understanding of the deleterious effects of cigarette smoking on muscle mass and highlights the importance of smoking cessation for muscle health.

Association of electronic-cigarette, number of cigarettes, and marijuana use with high-risk Human Papillomavirus (HPV) among men and women: A cross-sectional analysis of a nationally representative sample.

BACKGROUND: Smoking is associated with an increased risk of HPV infection. However, the use of e-cigarettes and marijuana, number of cigarettes, and serum cotinine concentrations in relation with HPV (6, 11, 16, 18) and high-risk HPV (16 or 18) infections in underserved and understudied populations remain poorly understood. METHODS: Data included 687 males and 664 females among whom 489 were White, 375 were Black and 342 were Hispanics from the NHANES 2013-2016 with HPV and high-risk HPV infections. Smoking history included current and past smokers, number of cigarettes, use of e-cigarettes, marijuana, and serum cotinine levels. Weighted multivariable-adjusted logistic regression models were conducted. RESULTS: High-risk HPV infection was associated with current smoking history plus ≥ 20 cigarettes/day (OR=1.92, 95 % CI=1.09, 3.37) in the overall population. E-cigarettes use (5 days) was positively associated with high-risk HPV infection (OR=2.43, 95 % CI=1.13, 5.22) in the overall population, with similar findings with e-cigarette (past 30 days) among women and Whites. CONCLUSION: High number of cigarettes, e-cigarette usage and marijuana were associated with HPV and high-risk HPV infections in the overall population. Most of these associations remained significant when stratified by gender and race/ethnicity. Increasing use of e-cigarettes and marijuana in these population warrants further investigation for the prevention of HPV infection and related cancers.

Secondhand Nicotine Absorption From E-Cigarette Vapor vs Tobacco Smoke in Children.

Importance: With the prevalence of e-cigarette use (vaping) increasing worldwide, there are concerns about children's exposure to secondhand vapor. Objective: To compare nicotine absorption among children who are (1) exposed to secondhand tobacco smoke only or (2) exposed to secondhand vapor only with (3) those exposed to neither. Design, Setting, and Participants: The US Continuous National Health and Nutrition Examination Survey (NHANES) is a repeat cross-sectional survey. Participants are interviewed in their homes and, several days after, visit a mobile examination center to provide biological specimens. This study uses data from a nationally representative sample of US households from 2017 to 2020. Participants were children aged 3 to 11 years with serum cotinine levels incompatible with current firsthand nicotine use (ie, <15 µg/L). The final analysis was conducted on January 9, 2024. Exposures: Reported exposure to secondhand smoke or vapor indoors in the past 7 days (only secondhand smoke, only secondhand vapor, or neither). Covariates included age, sex, ethnicity, family income, body weight, and height. Main Outcomes and Measures: The primary outcome was serum cotinine concentration, an objective biomarker of nicotine absorption. Geometric mean cotinine levels and 95% CIs were calculated using log-normal tobit regression, accounting for the complex survey design and weights. Results: The mean (SD) age of the 1777 children surveyed was 7.4 (2.6) years, 882 (49.6%) were female, and 531 (29.9%) had family incomes below the poverty level. Nicotine absorption, as indexed by serum cotinine level, was highest among children only exposed to secondhand smoke (0.494 µg/L µg/L; 95% CI, 0.386-0.633 µg/L), followed by those exposed only to secondhand vapor (0.081 µg/L; 95% CI, 0.048-0.137 µg/L), equating to 83.6% (95% CI, 71.5%-90.5%; P < .001) lower nicotine absorption. Among children with no reported secondhand exposure, the geometric mean cotinine level was 0.016 µg/L (95% CI, 0.013-0.021 µg/L), or 96.7% (95% CI, 95.6%-97.6%; P < .001) lower than for those with exposure to secondhand smoke. Results were similar after covariate adjustment. Conclusions and Relevance: In this cross-sectional study of US children, nicotine absorption was much lower in children who were exposed to secondhand vapor vs secondhand smoke, but higher than in those exposed to neither. These findings suggest that switching from smoking to vaping indoors may substantially reduce, but not eliminate, children's secondhand exposure to nicotine and other noxious substances.

Gas chromatography-mass spectrometry determination of nicotine and cotinine in urine: A study of the effect of passive smoking.

RATIONALE: Recent data suggest that passive smoking has a risk comparable to active smoking. Passive smoking is considered dangerous in children and is suspected as a cause of asthma. However, some reports are opposing such claims, indicating the need for solid results and large-scale studies. This scientific work aims to develop a method for the determination of nicotine (NCOT) and major nicotine's metabolite cotinine (COT) in urine samples, using gas chromatography-mass spectrometry (GC-MS). METHODS: Analysis was performed using a gas chromatograph Agilent Technologies 7890A with an MS 5975C inert XL, EI/CI MSD with Triple-Axis detector. For sample preparation, liquid-liquid extraction was applied after an optimization study with different extraction media. Eventually, 1 mL of dichloromethane was selected for the extraction of 0.5 mL of urine. Suitable chromatographic conditions were found for the rapid and accurate determination of NCOT and COT. Injection of 2 µL was performed using GC-MS, and selected ion monitoring (SIM) analysis was performed with the following ions (m/z): 162 (quantifier ion) and 84, 133, 161 qualifier ions for NCOT, and 176 (quantifier ion) and 98, 118, 119, 147 qualifier ions for COT. Nicotine-D4 (NCOT-D4) and cotinine-D3 (COT-D3) were used as internal standards with quantifier ions 101 and 166, respectively. The retention time (Rt) for NCOT was 7.557 min and 9.743 min for COT. RESULTS: The method was validated following international principles, assessing characteristics such as absolute recovery, carryover, linearity, specificity, selectivity, accuracy, precision, and stability. The method showed a linear dynamic range from 0.5 to 50 ng/mL, and the limits of detection and quantification were for both NCOT and COT 0.2 and 0.5 ng/mL, respectively. Validation results were found satisfactory. Finally, the method was applied to the analysis of 60 clinical pediatric samples obtained from Aristotle University's pediatric clinic to check for possible exposure to smoke. Concentration levels ranged between 0.5 and 16.2 ng/mL for NCOT and between 1.0 and 25.1 ng/mL for COT. CONCLUSIONS: A rapid, sensitive, accurate, and simple method was developed and used as a tool for the confirmation of passive smoking in children. It is the first method applied to the analysis of such samples belonging to nonsmokers of young age. The total runtime of the GC-MS analysis was short (20 min), and the pretreatment protocol was simple, giving the ability for analysis of a large number of samples on a daily routine basis.