Bridging Differences in Cohort Analyses of the Relationship between Secondhand Smoke Exposure during Pregnancy and Birth Weight: The Transportability Framework in the ECHO Program.

BACKGROUND: Estimates for the effects of environmental exposures on health outcomes, including secondhand smoke (SHS) exposure, often present considerable variability across studies. Knowledge of the reasons behind these differences can aid our understanding of effects in specific populations as well as inform practices of combining data from multiple studies. OBJECTIVES: This study aimed to assess the presence of effect modification by measured sociodemographic characteristics on the effect of SHS exposure during pregnancy on birth weights that may drive differences observed across cohorts. We also aimed to quantify the extent to which differences in the cohort mean effects observed across cohorts in the Environmental influences on Child Health Outcomes (ECHO) consortium are due to differing distributions of these characteristics. METHODS: We assessed the presence of effect modification and transportability of effect estimates across five ECHO cohorts in a total of 6,771 mother-offspring dyads. We assessed the presence of effect modification via gradient boosting of regression trees based on the H-statistic. We estimated individual cohort effects using linear models and targeted maximum likelihood estimation (TMLE). We then estimated transported effects from one cohort to each of the remaining cohorts using a robust nonparametric estimation approach relying on TMLE estimators and compared them to the original effect estimates for these cohorts. RESULTS: Observed effect estimates varied across the five cohorts, ranging from significantly lower birth weight associated with exposure [-167.3g; 95% confidence interval (CI): -270.4, -64.1] to higher birth weight with wide CIs, including the null (42.4g; 95% CI: -15.0, 99.8). Transported effect estimates only minimally explained differences in the point estimates for two out of the four cohort pairs. DISCUSSION: Our findings of weak to moderate evidence of effect modification and transportability indicate that unmeasured individual-level and contextual factors and sources of bias may be responsible for differences in the effect estimates observed across ECHO cohorts. https://doi.org/10.1289/EHP13961.

Early-life tobacco smoke exposure and stroke risk: a prospective study of 341,783 and 352,737 UK Biobank participants.

INTRODUCTION: Stroke is a life-threatening condition that causes a major medical burden globally. The currently used methods for the prevention or prediction of stroke have certain limitations. Exposure to tobacco in early life, including smoking during adolescence and maternal smoking during pregnancy, can affect adolescent development and lead to several negative outcomes. However, the association between early-life tobacco exposure and stroke is not known. METHODS: In this prospective cohort study, for the analyses involving exposure to maternal smoking during pregnancy and age of smoking initiation, we included 304,984 and 342,893 participants, respectively., respectively from the UK Biobank. Cox proportional hazard regression model and subgroup analyses were performed to investigate the association between early-life tobacco exposure and stroke. Mediation analyses were performed to identify the mediating role of biological aging in the association between early tobacco exposure and stroke. RESULTS: Compared with participants whose mothers did not smoke during pregnancy, participants whose mothers smoked during pregnancy showed an 11% increased risk of stroke (HR: 1.11, 95% CI: 1.05-1.18, P < 0.001). Compared with participants who never smoked, participants who smoked during adulthood, adolescence and childhood showed a 22%, 24%, and 38% increased risk of stroke during their adulthood, respectively. Mediation analysis indicated that early-life tobacco exposure can cause stroke by increasing biological aging. CONCLUSION: This study reveals that exposure to tobacco during early life is associated with an increased risk of experiencing a stroke, and increased biological aging can be the underlying mechanism.

Association between secondhand smoke exposure and serum sex hormone concentrations among US female adults: a cross-sectional analysis using data from the National Health and Nutrition Examination Survey, 2013-2016.

OBJECTIVE: To estimate the association between secondhand smoke (SHS) exposure and serum sex hormone concentrations in female adults (never smokers and former smokers). DESIGN: Cross-sectional analysis. SETTING: US National Health and Nutrition Examination Survey, 2013-2016. OUTCOME MEASURES: Serum sex hormone measures included total testosterone (TT) and oestradiol (E2), sex hormone-binding globulin (SHBG), the ratio of TT and E2 and free androgen index (FAI). Isotope dilution-liquid chromatography tandem mass spectrometry was used to measure serum TT and E2. SHBG was measured using immunoassay. The ratio of TT and E2 and FAI were calculated. SHS exposure was defined as serum cotinine concentration of 0.05-10 ng/mL. PARTICIPANTS: A total of 622 female participants aged ≥20 years were included in the analysis. RESULTS: For never smokers, a doubling of serum cotinine concentration was associated with a 2.85% (95% CI 0.29% to 5.47%) increase in TT concentration and a 6.29% (95% CI 0.68% to 12.23%) increase in E2 in fully adjusted models. The never smokers in the highest quartile (Q4) of serum cotinine level exhibited a 10.30% (95% CI 0.78% to 20.72%) increase in TT concentration and a 27.75% (95% CI 5.17% to 55.17%) increase in E2 compared with those in the lowest quartile (Q1). For former smokers, SHBG was reduced by 4.36% (95% CI -8.47% to -0.07%, p for trend=0.049) when the serum cotinine level was doubled, and the SHBG of those in Q4 was reduced by 17.58% (95% CI -31.33% to -1.07%, p for trend=0.018) compared with those in Q1. CONCLUSION: SHS was associated with serum sex hormone concentrations among female adults. In never smokers, SHS was associated with increased levels of TT and E2. In former smokers, SHS was associated with decreased SHBG levels.

Association between lipid profiles and cigarette smoke among adults in the Persian cohort (Shahedieh) study.

OBJECTIVES: Exposure to cigarette smoke introduces a large amount of nicotine into the bloodstream through the lungs. So, smoking can be a risk factor for many diseases. The present study was conducted to investigate the effect of active and passive cigarette smoke on the blood lipid profile and dyslipidemia. METHODS: This cross-sectional study was performed on 5052 individuals who participated in the recruitment phase of the Shahedieh cohort study. A logistic regression model was used to investigate the relationship between smoking exposure status and lipid profiles. RESULTS: The prevalence of abnormal low-density lipoprotein-cholesterol (LDL-C), abnormal HDL-C, abnormal total cholesterol (TC), abnormal triglyceride (TG), and dyslipidemia were 254 (5.00%), 562 (11.10%), 470 (9.30%), 1008 (20.00%), and 1527 (30.20%), respectively. Adjusting for confounders, it was observed that current smokers had higher odds of having abnormal HDL-C [OR (95% CI), 2.90 (2.28-3.69)], abnormal TG [OR (95% CI), 1.71 (1.38-2.13)] and dyslipidemia [OR (95% CI), 1.86 (1.53-2.25)]. Ex-smokers also had greater odds of abnormal HDL-C [OR (95% CI), 1.51 (1.06-2.16)] compared to non-smokers who were not exposed to cigarette smoke. CONCLUSIONS: The findings indicated that current smokers had higher TG and lower HDL. So, necessary measures should be taken to reduce smoking. The findings also showed that the prevalence of abnormal TG and HDL in ex-smokers was lower than in current smokers. Therefore, the existence of incentive policies to quit smoking seems necessary.

Association between passive smoking and dental caries status in children: A cross-sectional analytical study.

BACKGROUND: Several risk factors contribute to the development of dental caries in children, including sociodemographic, dietary, oral hygiene-related and other miscellaneous factors. Maternal smoking was highly associated with dental caries when compared to smoking by fathers or other household members. OBJECTIVES: The aim of the study was to determine the prevalence of dental caries and their association with exposure to environmental tobacco smoke (ETS) among 5- to 10-year-old students attending private and government schools. MATERIAL AND METHODS: A cross-sectional analytical study was conducted among schoolchildren. Data was collected from the primary caregivers using a pre-tested form to assess the ETS exposure under 5 domains based on history: antenatal exposure; exposure during the index period; exposure in the school neighborhood; exposure in restaurants/roadside stalls; and exposure in bus stops/railway stations. Dental caries was assessed based on the World Health Organization (WHO) guidelines from 1997. The association was reported using prevalence ratios (PRs) (95% confidence interval (CI)). RESULTS: Data was obtained from 211 schoolchildren attending government (39.8%) and private schools (60.2%). The overall prevalence (95% CI) of dental caries was 49.3% (42.5-56.1%). Among all the risk factors evaluated in the study, exposure to ETS was associated with a significantly increased risk of dental caries. The adjusted prevalence ratio (APR) of ETS exposure varied with the mother's educational status and high sugar exposure, although this was statistically insignificant. CONCLUSIONS: The prevalence of dental caries among schoolchildren aged 5 to 10 years in the city was moderate and similar to the national average. Among the risk factors assessed in the study, antenatal exposure to ETS was found to significantly increase the prevalence of dental caries by 41% after adjusting for other factors. Therefore, it is important to educate parents on the causal role of ETS exposure in dental caries.

[A study on the dual use of e-cigarettes and cigarettes among adolescents in Shandong Province].

Objective: To understand the current status and its associated factors of dual use of e-cigarettes and cigarettes among adolescents in Shandong Province and explore the reasons for dual use behavior. Methods: A self-administered survey was conducted among 7 999 middle school students who were selected by stratified multi-stage cluster sample method. Data were weighted and analyzed by the SPSS 25.0 complex program. Results: In Shandong Province, the prevalence rates of attempting and current dual use of e-cigarettes and cigarettes among adolescents appeared as 7.7% and 1.3%, respectively. Male, friends smoking, and secondhand smoke exposure in the past 7 days were risk factors for dual use. Compared with cigarette smokers, dual users have no differences in cognition and behavior in quitting smoking (P>0.05). The main reason for dual users to smoke e-cigarettes was curiosity. Conclusions: Dual use of e-cigarettes and cigarettes is common among adolescents in Shandong Province, and its influencing factors are similar to traditional cigarettes. Dual use is not a transitional stage for smoking cessation. Dual users are more likely to continue smoking in the future, which should be paid attention and concern.

Prevalence of Wheezing and Its Association with Environmental Tobacco Smoke Exposure among Rural and Urban Preschool Children in Mpumalanga Province, South Africa.

BACKGROUND: This study aimed to investigate the prevalence of wheezing and its association with environmental tobacco smoke exposure among rural and urban preschool children in Mpumalanga province, South Africa, an area associated with poor air quality. METHODS: In this study, parents/caregivers of preschool children (n = 3145) completed a modified International Study of Asthma and Allergies in Childhood (ISAAC) questionnaire. Data were analysed using multiple logistic regression models. RESULTS: The overall prevalence of Wheeze Ever was 15.14%, with a higher prevalence in urban preschoolers than rural preschoolers (20.71% vs. 13.30%, p < 0.000). Moreover, the total prevalence of Asthma Ever was 2.34%. The prevalence was greater in urban preschoolers than in rural preschoolers (3.92% vs. 1.81%, p < 0.001). In the final adjusted model, both urban- and rural-area children who lived with one or more people who smoked in the same household (WE: OR 1.44, 95% CI 1.11-1.86) (CW: OR 2.09, 95% CI 1.38-3.16) and (AE: OR 2.49, 95% CI 1.12-5.54) were found to have an increased likelihood of having Wheeze Ever, Current Wheeze, and Asthma Ever as compared to those who lived with non-smokers. CONCLUSIONS: The implementation of smoking limits and prohibition is crucial in areas that are frequented or utilized by children. Hence, it is imperative for healthcare providers to actively champion the rights of those who do not smoke within the society, while also endorsing legislative measures aimed at curtailing the extent of tobacco smoke exposure.

New Estimates of Smoking-Attributable Mortality in the U.S. From 2020 Through 2035.

INTRODUCTION: The often-cited Centers for Disease Control and Prevention (CDC) estimate of 480,000 annual U.S. smoking-attributable deaths (SADs), including 439,000 first-hand smoke deaths, derives from 2005 to 2009 data. Since then, adult smoking prevalence has decreased by 40%, while the population has grown and the smoking population aged. An updated estimate is presented to determine whether the CDC figure remains accurate or has changed substantially. In addition, the likely annual smoking-related mortality toll is projected through 2035. METHODS: A well-established model of smoking prevalence and health effects is employed to estimate annual SADs among individuals exposed to first-hand smoke in the U.S. for two distinct periods: 2005-2009 and 2020-2035. The estimate for 2005-2009 serves as a benchmark to evaluate the reliability of the model's estimate in comparison to CDC's. The projections for 2020-2035 provide up-to-date figures for SADs, predicting how annual SADs are likely to change in the coming years. Data were collected between 2005 and 2020. The analysis was conducted in 2023. RESULTS: This study's estimate of 420,000 first-hand smoke deaths over 2005-2009 is 95.7% of CDC's estimate during the same period. The model projections indicate that SADs among individuals who currently smoke or formerly smoked have increased modestly since 2005-2009. Beginning in 2020, annual SADs will remain relatively stable at approximately 450,000 before starting to decline around 2030. CONCLUSIONS: These findings suggest that the CDC estimate of the annual mortality burden of smoking remains valid. Despite U.S. population growth and the aging of the smoking population, substantial reductions in smoking will finally produce a steady, if gradual, decline in SADs beginning around 2030.

Association Between Secondhand Smoke Exposure and Nonalcoholic Fatty Liver Disease in the General U.S. Adult Nonsmoker Population.

INTRODUCTION: Smoking is a cause of nonalcoholic fatty liver disease (NAFLD), but the dose-response relationship between secondhand smoke exposure (SHS) and NAFLD is unclear. This study sought to determine the relationship between SHS and NAFLD risk among adult nonsmokers in the United States. AIMS AND METHODS: Data from 7412 adult nonsmokers aged ≥20 years who participated in the National Health and Nutrition Examination Survey (NHANES) between 2007 and 2016 were used in this study. SHS was defined as a nonsmoker with a serum cotinine concentration of 0.05-10.00 ng/mL. NAFLD was identified using the U.S. fatty liver index (USFLI), hepatic steatosis index (HSI), and fatty liver index (FLI). Weighted multivariable logistic regression and restricted cubic spline models were applied to evaluate the relationship between SHS and NAFLD risk. RESULTS: The participants had a weighted mean age of 49.2 years, and 55.5% were female. SHS was associated with NAFLD (odds ratio [OR] 1.22; 95% confidence interval CI: 1.05 to 1.42), showing a linear dose-response relationship (natural log of cotinine level: OR 1.10, 95% CI: 1.05 to 1.17). Sensitivity analyses using different NAFLD definitions (HSI: OR 1.21, 95% CI: 1.01 to 1.46; FLI: OR 1.26, 95% CI: 1.06 to 1.49), excluding participants taking hepatotoxic drugs, and propensity score-adjusted analysis yielded similar results. The association between SHS and NAFLD was consistent in analyses stratified by age, sex, and race/ethnicity. CONCLUSIONS: Among this nationally representative sample of U.S. adults, SHS had a linear dose-response relationship with the risk of NAFLD, suggesting that measures to lower SHS might lower NAFLD risk. IMPLICATIONS: This study assessed the association between secondhand smoke exposure and the risk of nonalcoholic fatty liver disease (NAFLD) using data from 7412 adult nonsmokers aged 20 years or older who participated in the United States NHANES between 2007 and 2016. Secondhand smoke exposure was measured using serum cotinine levels. Three different noninvasive indexes were used to measure NAFLD. Secondhand smoke exposure was associated with an increased risk of NAFLD, with a linear dose-response relationship. The results of sensitivity analyses and subgroup analyses were consistent.

Sources of Tobacco Smoke Exposure and Their Associations With Serum Cotinine Levels Among US Children and Adolescents.

INTRODUCTION: We assessed tobacco smoke exposure (TSE) levels based on private and public locations of TSE according to race and ethnicity among US school-aged children ages 6-11 years and adolescents ages 12-17 years. AIMS AND METHODS: Data were from 5296 children and adolescents who participated in the National Health and Nutrition Examination Survey (NHANES) 2013-2018. Racial and ethnic groups were non-Hispanic white, black, other or multiracial, and Hispanic. NHANES assessed serum cotinine and the following TSE locations: homes and whether smokers did not smoke indoors (home thirdhand smoke [THS] exposure proxy) or smoked indoors (secondhand [SHS] and THS exposure proxy), cars, in other homes, restaurants, or any other indoor area. We used stratified weighted linear regression models by racial and ethnic groups and assessed the variance in cotinine levels explained by each location within each age group. RESULTS: Among 6-11-year-olds, exposure to home THS only and home SHS + THS predicted higher log-cotinine among all racial and ethnic groups. Non-Hispanic white children exposed to car TSE had higher log-cotinine (ß = 1.64, 95% confidence interval [CI] = 0.91% to 2.37%) compared to those unexposed. Non-Hispanic other/multiracial children exposed to restaurant TSE had higher log-cotinine (ß = 1.13, 95% CI = 0.23% to 2.03%) compared to those unexposed. Among 12-17-year-olds, home SHS + THS exposure predicted higher log-cotinine among all racial and ethnic groups, except for non-Hispanic black adolescents. Car TSE predicted higher log-cotinine among all racial and ethnic groups. Non-Hispanic black adolescents with TSE in another indoor area had higher log-cotinine (ß = 2.84, 95% CI = 0.85% to 4.83%) compared to those unexposed. CONCLUSIONS: TSE location was uniquely associated with cotinine levels by race and ethnicity. Smoke-free home and car legislation are needed to reduce TSE among children and adolescents of all racial and ethnic backgrounds. IMPLICATIONS: Racial and ethnic disparities in TSE trends have remained stable among US children and adolescents over time. This study's results indicate that TSE locations differentially contribute to biochemically measured TSE within racial and ethnic groups. Home TSE significantly contributed to cotinine levels among school-aged children 6-11 years old, and car TSE significantly contributed to cotinine levels among adolescents 12-17 years old. Racial and ethnic differences in locations of TSE were observed among each age group. Study findings provide unique insight into TSE sources, and indicate that home and car smoke-free legislation have great potential to reduce TSE among youth of all racial and ethnic backgrounds.

Discriminative Accuracy of Chronic Obstructive Pulmonary Disease Screening Instruments in 3 Low- and Middle-Income Country Settings.

Importance: Most of the global morbidity and mortality in chronic obstructive pulmonary disease (COPD) occurs in low- and middle-income countries (LMICs), with significant economic effects. Objective: To assess the discriminative accuracy of 3 instruments using questionnaires and peak expiratory flow (PEF) to screen for COPD in 3 LMIC settings. Design, Setting, and Participants: A cross-sectional analysis of discriminative accuracy, conducted between January 2018 and March 2020 in semiurban Bhaktapur, Nepal; urban Lima, Peru; and rural Nakaseke, Uganda, using a random age- and sex-stratified sample of the population 40 years or older. Exposures: Three screening tools, the COPD Assessment in Primary Care to Identify Undiagnosed Respiratory Disease and Exacerbation Risk (CAPTURE; range, 0-6; high risk indicated by a score of 5 or more or score 2-5 with low PEF [<250 L/min for females and <350 L/min for males]), the COPD in LMICs Assessment questionnaire (COLA-6; range, 0-5; high risk indicated by a score of 4 or more), and the Lung Function Questionnaire (LFQ; range, 0-25; high risk indicated by a score of 18 or less) were assessed against a reference standard diagnosis of COPD using quality-assured postbronchodilator spirometry. CAPTURE and COLA-6 include a measure of PEF. Main Outcomes and Measures: The primary outcome was discriminative accuracy of the tools in identifying COPD as measured by area under receiver operating characteristic curves (AUCs) with 95% CIs. Secondary outcomes included sensitivity, specificity, positive predictive value, and negative predictive value. Results: Among 10 709 adults who consented to participate in the study (mean age, 56.3 years (SD, 11.7); 50% female), 35% had ever smoked, and 30% were currently exposed to biomass smoke. The unweighted prevalence of COPD at the 3 sites was 18.2% (642/3534 participants) in Nepal, 2.7% (97/3550) in Peru, and 7.4% (264/3580) in Uganda. Among 1000 COPD cases, 49.3% had clinically important disease (Global Initiative for Chronic Obstructive Lung Disease classification B-D), 16.4% had severe or very severe airflow obstruction (forced expiratory volume in 1 second <50% predicted), and 95.3% of cases were previously undiagnosed. The AUC for the screening instruments ranged from 0.717 (95% CI, 0.677-0.774) for LFQ in Peru to 0.791 (95% CI, 0.770-0.809) for COLA-6 in Nepal. The sensitivity ranged from 34.8% (95% CI, 25.3%-45.2%) for COLA-6 in Nepal to 64.2% (95% CI, 60.3%-67.9%) for CAPTURE in Nepal. The mean time to administer the instruments was 7.6 minutes (SD 1.11), and data completeness was 99.5%. Conclusions and Relevance: This study demonstrated that screening instruments for COPD were feasible to administer in 3 low- and middle-income settings. Further research is needed to assess instrument performance in other low- and middle-income settings and to determine whether implementation is associated with improved clinical outcomes.

Urinary cotinine assessment of maternal smoking and environmental tobacco smoke exposure status and its associations with perinatal outcomes: a cross-sectional birth study.

Tobacco consumption and environmental tobacco smoke (ETS) exposure remains an important public health concern. Pregnant women require particular attention as active and passive smoking during pregnancy are associated with multiple adverse perinatal outcomes. This study aimed to biochemically validate self-reported smoking and ETS exposure status among pregnant women, to more precisely ascertain its association with adverse perinatal outcomes. Data refers to 595 pregnant women who sought prenatal care in a public hospital in Porto, Portugal. A standard questionnaire on smoking and ETS-related variables was completed. Urinary cotinine (UC) concentrations were assessed by solid-phase competitive ELISA, in maternal urine samples collected on the day of delivery. The results showed that the optimal UC cut-off value to distinguish smokers from non-smokers and within non-smokers those who were exposed to ETS from those non-exposed in the third trimester of pregnancy was 74.1 ng/mL (sensitivity and specificity of 96.7% and 98.0%, respectively) and 1.6 ng/mL (sensitivity of 66.2% and specificity of 75.7%, respectively). The agreement between maternal self-reported and UC-based smoking status was very good (κ=0.919, p<0.001), but much lower for ETS exposure (κ=0.386, p<0.001). Maternal active smoking in the third trimester of pregnancy was associated with a significant decrease in birth weight, length and head circumference of 157.66 g (95% CI: -245.81, -69.52; p<0.001), 0.78 cm (95% CI: -1.22, -0.34; p=0.001) and 0.39 cm (95% CI: -0.70, -0.07; p=0.016), respectively. Maternal ETS exposure in the third trimester of pregnancy was associated with a non-significant increase in birth weight of 38.37 g (95% CI: -28.91, 105.64; p=0.263). Furthermore, maternal smoking cessation was associated with the increase of approximately 172 g in birth weight (95% CI: 50.00, 293.19). As such, there is an urgent need for increased public health awareness campaigns to encourage smoking cessation during pregnancy, in order to improve perinatal outcomes.

Investigating the association between smoking, environmental tobacco smoke exposure and reward-related brain activity in adolescent experimental smokers.

Reduced anticipatory reward-related activity, especially in the ventral striatum (VS), may underly adolescent vulnerability to develop nicotine dependence. It remains unclear whether nicotine uptake caused by environmental tobacco smoke (ETS) exposure, known to be associated with future smoking, might prompt similar changes in the brain's reward system, rendering adolescents vulnerable for development of nicotine dependence. To address this question, we tested whether current ETS exposure and monthly smoking are associated with VS hypoactivity for non-drug rewards in experimental smoking adolescents. One-hundred adolescents performed a monetary incentive delay task while brain activity was measured using fMRI. To test the hypothesized relationship, we used a variety of approaches: (1) a whole-brain voxel-wise approach, (2) an region-of-interest approach in the VS using frequentist and Bayesian statistics and (3) a small volume voxel-wise approach across the complete striatum. The results converged in revealing no significant relationships between monthly smoking, ETS exposure and reward-related brain activation across the brain or in the (ventral) striatum specifically. However, Bayesian statistics showed only anecdotal evidence for the null hypothesis in the VS, providing limited insight into the (non-)existence of the hypothesized relationship. Based on these results, we speculate that blunted VS reward-related activity might only occur after relatively high levels of exposure or might be associated with more long term effects of smoking. Future studies would benefit from even larger sample sizes to reliably distinguish between the null and alternative models, as well as more objective measures of (environmental) smoking via using devices such as silicone wristbands.

Change in exposure of children to second-hand smoke with impact on children's health and change in parental smoking habits after smoking ban in Bavaria - a multiple cross-sectional study.

BACKGROUND: Concerns about smoking displacement from public places to private amenities aroused following smoking ban implementation in Bavaria in 2008. We analysed children's exposure to second-hand smoke (SHS) before and after the ban, its effect on children's health and prevalence of active smoking in adults. METHODS: Six cross-sectional surveys (n = 32,443) on pre-school children in Bavaria were analysed, two surveys before the smoking ban in years 2004 and 2005 (S1 and S2) and four after the ban in 2008, 2012, 2014 and 2016 (S4, S6, S7 and S8). Using multivariable logistic regression, we analysed change in children's intra- and extrauterine SHS exposure and its adverse health effects (Asthma, wheezing, bronchitis and neurodermatitis) as well as change in parental active smoking. RESULTS: The response rates were 78% for S1, 73% for S2, 61% for S4, 62% for S6, 56% for S7 and 54% for S8. Odds of parents never smoked at home in presence of children increased significantly from before to after the ban with odds ratios (OR) 1.17 (CI95% 1.01-1.35), 1.65 (CI95% 1.39-1.95), 2.85 (CI95% 2.32-3.51), 2.24 (CI95% 1.84-2.72) and 3.66 (CI95% 2.89-4.63) for S2, S4, S6, S7 and S8, respectively with S1 as reference. Compared to S4, odds of parents who were not actively smoking is significantly higher in S7 (OR = 1.13 (CI95% 1.03-1.24)) and S8 (OR = 1.24 (CI95% 1.13-1.36)). The odds of mothers who never smoked during pregnancy increased over time with OR = 1.22 (CI95% 1.06-1.40) for S2 and 1.57 (CI95% 1.33-1.86) for S8 compared to S1. Adverse health effects related to children's exposure to SHS are significantly less in S8 compared to S1. CONCLUSION: After 11 years of smoking ban in Bavaria, smoking displacement to homes was disproved. Exposure of children to SHS intrauterine and at home is decreasing. Number of parents who are not actively smoking is increasing over time. Prevalence of health problems in children related to exposure to SHS is decreasing.

The impact of second-hand smoke on ear, nose, and throat diseases and head and neck cancers in Japan: a cross-sectional study using a questionnaire and secondary data from the national health and nutrition survey.

BACKGROUND: The risk of head and neck cancers (HNCs) and ear, nose, and throat (ENT) diseases due to second-hand smoke (SHS) have not been fully assessed. OBJECTIVE: To determine which ENT diseases or HNCs are associated with SHS. MATERIAL AND METHODS: Data from a survey of a cross-sectional sample of ENT patients (n = 1228) on SHS exposure were compared to control-subject data (n = 6598) from a Japan National Health Survey. Multivariate logistic regression and estimated odds ratios (ORs) determined whether SHS-disease associations were related to exposure location and disease occurrence. RESULTS: SHS was significantly associated with acute tonsillitis (OR in workplaces, 2.24 [95% CI, 1.34-3.75]; OR in restaurants, 4.24 [95% CI, 2.50-7.19]; OR in leisure places, 4.72 [95% CI, 2.93-7.62]); recurrent tonsillitis (OR in restaurants, 4.24 [95% CI, 2.52-7.13]; OR in leisure places, 5.29 [95% CI, 3.31-8.46]); facial palsy (OR in home, 2.18 [95% CI, 1.25-3.81]; OR in leisure places, 3.41 [95% CI, 1.97-5.89]); hypopharyngeal cancer (OR in home, 2.51 [95% CI, 1.18-5.36]; OR in workplaces, 2.53 [95% CI, 1.24-5.15]); and laryngeal cancer (OR in home, 2.44 [95% CI, 1.04-5.68]; OR in leisure places, 2.25 [95% CI, 1.00-5.07]). CONCLUSIONS AND SIGNIFICANCE: SHS may contribute to HNCs and ENT diseases, suggesting that merely being in the presence of smokers could increase the risk of head and neck morbidities.

Tobacco smoke exposure and fractional exhaled nitric oxide levels among U.S. adolescents.

BACKGROUND: Fractional exhaled nitric oxide (FeNO) can objectively guide clinical practice in the assessment, diagnosis, and treatment of eosinophilic airway inflammation. FeNO values may be affected by current smoking, but the role of tobacco smoke exposure (TSE) is understudied. OBJECTIVE: This study investigated the associations between biochemically validated and self-reported TSE and FeNO levels among U.S. nonsmoking adolescents without asthma. METHODS: National Health and Nutrition Examination Survey 2007-2012 data were used. TSE was assessed via serum cotinine and self-reported measures. We assessed FeNO continuously and using cutpoints of >35 ppb and >50 ppb to indicate likely eosinophilic inflammation in children and adults, respectively. We conducted linear and logistic regression adjusting for potential covariates. RESULTS: Overall, 34.0% of adolescents had low cotinine (0.05-2.99 ng/ml), 6.2% had high cotinine (≥3.00 ng/ml), and 11.9% had home TSE. Compared to adolescents with no/minimal cotinine, adolescents with high cotinine were at reduced odds to have FeNO >35 ppb (adjusted odds ratio [aOR] = 0.54, 95%CI = 0.43,0.69). Adolescents with low cotinine had lower FeNO values (ß = -2.05, 95%CI = -3.61,-0.49), and were also at decreased odds to have FeNO >35 ppb (aOR = 0.74, 95%CI = 0.66,0.83) and FeNO >50 ppb (aOR = 0.62, 95%CI = 0.53,0.72). Adolescents with home TSE were at reduced odds to have FeNO >50 ppb (aOR = 0.72, 95%CI = 0.57,0.91) than adolescents without home TSE. Adolescents with a higher number of cigarettes/day smoked inside their home were at reduced odds to have FeNO >35 ppb (OR = 0.98, 95%CI = 0.97,0.99) and FeNO >50 ppb (OR = 0.98, 95%CI = 0.96,0.99). CONCLUSIONS: TSE was associated with decreased FeNO levels. The addition of TSE may be clinically important when interpreting thresholds for FeNO.

Decreased head circumference at birth associated with maternal tobacco smoke exposure during pregnancy on the Japanese prospective birth cohort study.

Maternal tobacco smoke exposure during pregnancy impairs fetal body size, including head circumference (HC) at birth; however, the mechanism still remains unclear. This analysis using a large prospective cohort study evaluated the impact of maternal tobacco exposure on their offspring's HC and the relationship with placental weight ratio (PWR) and placental abnormalities. Parents-children pairs (n = 84,856) were included from the 104,065 records of the Japan Environmental and Children's Study. Maternal perinatal clinical and social information by self-administered questionnaires, offspring's body size, and placental information were collected. Data were analyzed with binominal logistic regression analysis and path analysis. Logistic regression showed significantly elevated adjusted odds ratio (aOR) (1.653, 95% CI 1.387-1.969) for the impact of maternal smoking during pregnancy on their offspring's smaller HC at birth. Maternal exposure to environmental tobacco smoke in the non-smoking group did not increase aOR for the smaller HC. Path analysis showed that maternal smoking during pregnancy decreased the offspring's HC directly, but not indirectly via PWR or placental abnormalities. The quitting smoking during pregnancy group did not increase aOR for the smaller HC than the non-smoking group, suggesting that quitting smoking may reduce their offspring's neurological impairment even after pregnancy.

Associations of exposure to secondhand smoke with hypertension risk and blood pressure values in adults.

BACKGROUND: The effects of environmental chemical exposure on blood pressure (BP) have been confirmed, but the association between exposure to secondhand smoke (SHS) and hypertension risk and BP in the general population remains unknown. METHODS: Cross-sectional associations between SHS exposure and hypertension risk and BP values were evaluated using data for subjects who participated in the National Health and Nutrition Examination Survey (NHANES), 1999-2016. Logistic regression and linear regression were performed after adjusting for age, sex, race, alcohol consumption, poverty-to-income ratio (PIR), body mass index (BMI), estimated glomerular filtration rate, physical activity, diabetes, cardiovascular disease, and NHANES cycle. Restricted cubic spline models were created to display the potential nonlinear association between SHS and BP levels. RESULTS: Higher risk of hypertension was found at the highest SHS concentrations (OR = 1.13, 95% CI 1.04, 1.24, P for trend = 0.007). Additionally, SHS exposure had a strong positive association with systolic blood pressure (SBP) but was negatively associated with diastolic blood pressure (DBP). Furthermore, the nonlinear model result showed a significant association between SHS and SBP (P = 0.017); however, the nonlinear model result was not significant for SHS or DBP. CONCLUSIONS: Our results suggest a potential association between high SHS exposure and the risk of hypertension. Further research is needed to elucidate the underlying mechanisms.

Global trends in the prevalence of secondhand smoke exposure among adolescents aged 12-16 years from 1999 to 2018: an analysis of repeated cross-sectional surveys.

BACKGROUND: Secondhand smoke exposure can cause morbidity and premature mortality. However, the global prevalence of, and trends in, secondhand smoke exposure among adolescents are poorly documented. We aimed to assess the prevalence of, and trends in, secondhand smoke exposure among adolescents from 1999 to 2018. METHODS: We did an analysis of the most recent data from the Global Youth Tobacco Survey (GYTS), a nationally representative, self-administered, school-based cross-sectional survey of tobacco use and related factors among adolescents aged 12-16 years worldwide. Data from 142 countries and territories that had done a GYTS between 2010 and 2018, comprising 711 366 participants, were used to assess the prevalence of secondhand smoke exposure. Data from 131 countries and territories that had done two or more surveys between 1999 and 2018, comprising 1 405 458 participants, were used to assess trends in secondhand smoke exposure. The frequency of secondhand smoke exposure at home, in public places, or in any place was defined as follows, based on students' responses: 1 or more days, 3 or more days, 5 or more days, or daily during the past 7 days. FINDINGS: Based on the most recent surveys done in 142 countries between Jan 1, 2010, and Dec 31, 2018, the global prevalence of secondhand smoke exposure in any place was 62·9% (95% CI 61·7-64·1) on 1 or more days, 51·0% (49·8-52·1) on 3 or more days, 40·1% (38·9-41·2) on 5 or more days, and 32·5% (31·5-33·6) daily during the past 7 days. The prevalence of secondhand smoke exposure at home was 33·1% (95% CI 32·1-34·1) on 1 or more days, 20·1% (19·3-20·9) on 3 or more days, 14·9% (14·2-15·7) on 5 or more days, and 12·3% (11·7-13·0) daily during the past 7 days; and in public places the prevalence of secondhand smoke exposure was 57·6% (56·4-58·8) on 1 or more days, 43·4% (42·2-44·6) on 3 or more days, 30·3% (29·2-31·5) on 5 or more days, and 23·5% (22·5-24·5) daily during the past 7 days. Between Jan 1, 1999, and Dec 31, 2018, the prevalence of secondhand smoke exposure (on ≥1 day during the past 7 days) in any place decreased in 57 (43·5%) of 131 countries, increased in 27 (20·6%), and remained unchanged in 47 (35·9%). Although the prevalence of secondhand smoke exposure at home decreased in 86 (65·6%) countries, the prevalence in public places did not change in 46 (35·1%) countries and increased in 40 (30·5%). INTERPRETATION: Secondhand smoke exposure among adolescents remains a serious public health challenge worldwide. Although the prevalence of secondhand smoke exposure at home decreased in most countries, the prevalence in public places increased or remained unchanged in most countries between 1999 and 2018. These findings emphasise the need to strengthen smoke-free policies, especially in public places. FUNDING: Youth Team of Humanistic and Social Science of Shandong University, Jinan, China. TRANSLATION: For the Chinese translation of the abstract see Supplementary Materials section.

What differs former, light and heavy smokers? Evidence from a post-conflict setting.

BACKGROUND: Evidence suggests that people who live in regions affected by the armed conflict are more likely to smoke. OBJECTIVE: The purpose of this study was to assess factors associated with smoking status in a sample of students in the northern Kosovo province. MATERIALS AND METHODS: A total of 514 students enrolled in University in Kosovska Mitrovica, Kosovo, were recruited between April to June 2015 at Student Public Health Center during mandatory health checks. Participants filled in socio-demographic and behavioral questionnaire and Beck Depression Inventory (BDI). Based on responses about smoking, students were categorized in non-smokers, former smokers, light smokers (1-13 cigarettes/day) and heavy smokers (> 13 cigarettes/day). RESULTS: Of 514 students, 116 (22.6%) classified themselves as smokers. Higher education level of fathers (Odds ratio [OR]=2.89, 95% confidence interval [CI] 1.30-6.44, p=0.009), not living with smokers (OR=0.42, 95%CI 0.15-0.97, p=0.017) and longer exposure to second hand smoke (OR=1.07, 95%CI 1.01-1.13, p=0.036) was associated with former smoking. Studying medical and natural sciences (OR=2.07, 95%CI 1.05-4.18, p=0.040), consuming alcohol (OR=2.98, 95%CI 1.19-10.03, p=0.020), living with smokers (OR=2.88, 95%CI 1.49-5.56, p=0.002), longer exposure to second hand smoke (OR=1.06, 95%CI 1.01-1.11, p=0.019) and having a more intense depressive symptoms (OR=1.08, 95%CI 1.03-1.13, p=0.002) was associated with light smoking. Being male (OR=0.22, 95%CI 0.07-0.41, p=0.001), older (OR=1.47, 95%CI 1.21-1.78, p=0.001), living with smokers (OR=3.78, 95%CI 1.69-8.07, p=0.001), longer daily exposure to second-hand smoke (OR=1.10, 95%CI 1.04-1.16, p=0.001), and having more severe depressive symptoms (OR=1.12, 95%CI 1.07-1.18, p=0.001) were associated with heavy smoking. CONCLUSION: Smoking prevention and cessation programs should include the entire community, because exposure to environmental second hand smoke may facilitate initiation and more intense smoking. Screening of student smokers for depression should be prioritized in the process of rebuilding the framework for primary and secondary prevention in the post-conflict period.