Evaluating the validity of self-reported smoking in Mexican adolescents

Low-intensity daily smoking and mortality risk among Mexican women

OBJECTIVE

To examine the association between low-intensity smoking (10 or less cigarettes per day) and all-cause and cause-specific mortality risk among women who smoke and by age at cessation among women who previously smoked.

METHODS

In this study, 104 717 female participants of the Mexican Teachers' Cohort Study were categorised according to self-reported smoking status at baseline (2006/2008) and were followed for mortality through 2019. We estimated HRs and 95% CIs for all-cause and cause-specific mortality using multivariable Cox proportional hazards regression models with age as the underlying time metric.

RESULTS

Smoking as few as one to two cigarettes per day was associated with higher mortality risk for all causes (HR: 1.36; 95% CI 1.10 to 1.67) and all cancers (HR: 1.46; 95% CI 1.05 to 2.02), compared with never smoking. Similarly, slightly higher HRs were observed among participants smoking ≥3 cigarettes per day (all causes HR: 1.43; 95% CI 1.19 to 1.70; all cancers HR: 1.48; 95% CI 1.10 to 1.97; cardiovascular disease HR: 1.58; 95% CI 1.09 to 2.28).

CONCLUSIONS

In this large study of Mexican women, low-intensity smoking was associated with higher mortality risk for all causes and all cancers. Interventions are needed to promote cessation among women who smoke at low-intensity in Mexico, regardless of how few cigarettes they smoke per day.

Sex differences in clinical risk factors in obese ischemic stroke patients with a history of smoking

Clinical risk factors associated obesity and smoking, as well as their combined effect, are not fully understood. This study aims to determine sex differences in risk factors in a population of acute ischemic stroke (AIS) patients who are obese and with a history of previous or current smoking.

METHODS

A retrospective analysis of risk factors in male and female AIS patients with baseline data of obesity and current or previous history of smoking, smoking, and obesity alone was determined. The primary predictor and outcome are risk factors associated with male and female AIS patients. Baseline risk factors were analyzed using a multivariate regression analysis to determine specific risk factors linked with the combined effect of obesity and current or previous history of smoking''.

RESULTS

Male obese AIS patients who are current or previous smokers were more likely to be older patients(OR = 1.024, 95% CI, 1.022-1.047, P = 0.033) that present with coronary artery disease (OR = 1.806, 95% CI, 1.028-3.174, P = 0.040), a history of alcohol use (OR = 2.873, 95% CI, 1.349-6.166, P = 0.006), elevated serum creatinine (OR = 4.724, 95% CI, 2.171-10.281, P < 0.001) and systolic blood pressure (OR = 1.029, 95% CI, 1.011-1.047, P < 0.002). Females were more associated with depression (OR = 0.432, 95% CI, 0.244-0.764, P = 0.004), previous TIA (OR = 0.319, 95% CI, 0.142-0.714, P < 0.005), and higher levels of HDL (OR = 0.938, 95% CI, 0.915-0.962, P < 0.001).

CONCLUSION

Our results reveal sex differences in risk factors in obese AIS patients with a current or past history of smoking. This finding emphasizes the need to develop management strategies to improve the care of obese AIS patients who are either current or former smokers.

Evaluation of common carotid artery wall stiffness by shear wave elastography in smokers and non-smokers

INTRODUCTION

Smoking is one of the most important preventable causes of cardiovascular diseases. Vascular disease caused by smoking is associated with vascular endothelial damage, platelet aggregation, and adhesion. In our study, we examined the effect of chronic smoking on vessel wall stiffness in smokers and control group by measuring carotid artery wall stiffness by shear wave ultrasonography.

METHODS

Sixty-two smokers of similar ages and genders, and 67 people who never smoked in the last ten years were included as the control group in this cross-sectional study. Arterial wall stiffness over the common carotid arteries of all participants was measured by shear wave elastography (SWE). In addition, each patient's blood pressure, fasting blood glucose, body mass index (BMI), HDL and LDL cholesterol measurements were recorded.

RESULTS

Arterial wall stiffness values in smokers were found to be statistically significantly higher than in non-smokers. The mean of SWE measurements of the smokers was 47.3 ± 6.2 kPa, and that of the control group was 42.9 ± 4 kPa. The mean values of HDL and LDL of the smokers were 46.9 ± 5.6 mg/dL and 147.3 ± 9.3 mg/dL, respectively, and those of the control group were 50.3 ± 5.1 mg/dL and 136.9 ± 5.9 mg/dL. The LDL cholesterol values were statistically significantly higher in smokers compared to the control group, and HDL cholesterol values were statistically significantly lower in smokers.

CONCLUSIONS

In our study, the arterial wall stiffness values measured by the SWE technique were higher in smokers than non-smokers.

Black Americans' Diminished Return of Educational Attainment on Tobacco Use in Baltimore City

BACKGROUND

Socioeconomic status (SES) indicators such as educational attainment are fundamental factors affecting health. One mechanism through which education affects health is by reducing the likelihood of engaging in high-risk behaviors such as smoking. However, according to the marginalization-related diminished returns (MDRs) theory, the association between education and health may be weaker for marginalized populations such as Black than White, primarily due to racism and discrimination. However, little is known about the racial variations in the differential associations between educational attainment and tobacco use in a local setting.

AIM

This study aimed to investigate the differential association between educational attainment and tobacco use among racial groups in a community sample in Baltimore City.

METHODS

This cross-sectional study used data from a community survey conducted in 2012-2013 in Baltimore City among adults aged 18 years or older. The participants were 3501 adults. Univariate, bivariate, and logistic regression analyses were performed using Stata to investigate the racial difference in the association between education and two outcomes: current smoking status and menthol tobacco product use.

RESULTS

The study found that adults with a graduate degree were less likely to be current smokers (adjusted odds ratio [AOR]: 0.10, 95% confidence interval [CI]: 0.08-0.13) and menthol tobacco users (AOR: 0.10, 95% CI: 0.07-0.14) compared to those with less than high school diploma. The inverse associations between educational attainment and current smoking (AOR: 1.83, 95% CI: 1.05-3.21) and menthol tobacco product use (AOR: 4.73, 95% CI: 2.07-10.80) were weaker for Back individuals than those who were White.

CONCLUSION

Due to MDRs of educational attainment, while highly educated White adults show a low risk of tobacco use, educated Black adults remain at a disproportionately increased risk. The study emphasizes the need for better policies and programs that address minorities' diminished return of education for tobacco use.

Fathers' preconception smoking and offspring DNA methylation

BACKGROUND

Experimental studies suggest that exposures may impact respiratory health across generations via epigenetic changes transmitted specifically through male germ cells. Studies in humans are, however, limited. We aim to identify epigenetic marks in offspring associated with father's preconception smoking.

METHODS

We conducted epigenome-wide association studies (EWAS) in the RHINESSA cohort (7-50 years) on father's any preconception smoking (n = 875 offspring) and father's pubertal onset smoking < 15 years (n = 304), using Infinium MethylationEPIC Beadchip arrays, adjusting for offspring age, own smoking and maternal smoking. EWAS of maternal and offspring personal smoking were performed for comparison. Father's smoking-associated dmCpGs were checked in subpopulations of offspring who reported no personal smoking and no maternal smoking exposure.

RESULTS

Father's smoking commencing preconception was associated with methylation of blood DNA in offspring at two cytosine-phosphate-guanine sites (CpGs) (false discovery rate (FDR) < 0.05) in PRR5 and CENPP. Father's pubertal onset smoking was associated with 19 CpGs (FDR < 0.05) mapped to 14 genes (TLR9, DNTT, FAM53B, NCAPG2, PSTPIP2, MBIP, C2orf39, NTRK2, DNAJC14, CDO1, PRAP1, TPCN1, IRS1 and CSF1R). These differentially methylated sites were hypermethylated and associated with promoter regions capable of gene silencing. Some of these sites were associated with offspring outcomes in this cohort including ever-asthma (NTRK2), ever-wheezing (DNAJC14, TPCN1), weight (FAM53B, NTRK2) and BMI (FAM53B, NTRK2) (p < 0.05). Pathway analysis showed enrichment for gene ontology pathways including regulation of gene expression, inflammation and innate immune responses. Father's smoking-associated sites did not overlap with dmCpGs identified in EWAS of personal and maternal smoking (FDR < 0.05), and all sites remained significant (p < 0.05) in analyses of offspring with no personal smoking and no maternal smoking exposure.

CONCLUSION

Father's preconception smoking, particularly in puberty, is associated with offspring DNA methylation, providing evidence that epigenetic mechanisms may underlie epidemiological observations that pubertal paternal smoking increases risk of offspring asthma, low lung function and obesity.

Assessing tobacco use in Swedish young adults from self-report and urinary cotinine: a validation study using the BAMSE birth cohort

OBJECTIVES

Studies on health effects of tobacco often rely on self-reported exposure data, which is subjective and can lead to misclassification. The aim of this study was to describe the prevalence of cigarette smoking, snus and e-cigarette use, as well as to validate self-reported tobacco use among young adults in Sweden.

METHOD

Participants of a population-based Swedish cohort (n=3052), aged 22-25 years, assessed their tobacco use in a web questionnaire. Urinary cotinine was analysed in a subsample of the study population (n=998). The agreement between self-reported tobacco use and urinary cotinine was assessed using Cohen's Kappa coefficient (κ) at a cut-off level of 50 ng/mL.

RESULTS

Patterns of tobacco use differed between men and women. Among men, 20.0% reported daily snus use, 5.8% daily cigarette smoking and 5.6% any e-cigarette use. In contrast, 3.2% of the women reported daily snus use, 9.0% daily cigarette smoking and 2.4% any e-cigarette use. Among the tobacco use categories, daily snus users had the highest levels of cotinine. Of reported non-tobacco users, 3.5% had cotinine levels above the cut-off, compared with 68.0% among both occasional cigarette smokers and snus users, 67.5% among all e-cigarette users and 94.7% and 97.8% among daily cigarette smokers and snus users, respectively. Agreement between self-reported tobacco use and urinary cotinine was classified as strong for daily use of cigarettes (κ=0.824) and snus (κ=0.861), while moderate to weak for occasional smoking (κ=0.618), occasional snus use (κ=0.573) and any e-cigarette use (κ=0.576).

CONCLUSIONS

We found high validity of self-reported tobacco use in our study population, particularly for daily tobacco use. Further, we found that daily snus users were exposed to high levels of cotinine. Together with previous findings, our results indicate good validity of self-reported tobacco use among young adults.

Systematic review of intervention functions, theoretical constructs and cultural adaptations of school-based smoking prevention interventions in low-income and middle-income countries

OBJECTIVE

To identify the approaches and strategies used for ensuring cultural appropriateness, intervention functions and theoretical constructs of the effective and ineffective school-based smoking prevention interventions that were implemented in low-income and middle-income countries (LMICs).

DATA SOURCES

Included MEDLINE, EMBASE, Global Health, PsycINFO, Web of Science and grey literature which were searched through August 2022 with no date limitations.

ELIGIBILITY CRITERIA

We included randomised controlled trials (RCTs) with ≥6 months follow-up assessing the effect of school-based interventions on keeping pupils never-smokers in LMICs; published in English or Arabic.

DATA EXTRACTION AND SYNTHESIS

Intervention data were coded according to the Theoretical Domains Framework, intervention functions of Behaviour Change Wheel and cultural appropriateness features. Using narrative synthesis we identified which cultural-adaptation features, theoretical constructs and intervention functions were associated with effectiveness. Findings were mapped against the capability-motivation and opportunity model to formulate the conclusion. Risk of bias was assessed using the Cochrane risk of bias tool.

RESULTS

We identified 11 RCTs (n=7712 never-smokers aged 11-15); of which five arms were effective and eight (four of the effective) arms had a low risk of bias in all criteria. Methodological heterogeneity in defining, measuring, assessing and presenting outcomes prohibited quantitative data synthesis. We identified nine components that characterised interventions that were effective in preventing pupils from smoking uptake. These include deep cultural adaptation; raising awareness of various smoking consequences; improving refusal skills of smoking offers and using never-smokers as role models and peer educators.

CONCLUSION

Interventions that had used deep cultural adaptation which incorporated cultural, environmental, psychological and social factors, were more likely to be effective. Effective interventions considered improving pupils' psychological capability to remain never-smokers and reducing their social and physical opportunities and reflective and automatic motivations to smoke. Future trials should use standardised measurements of smoking to allow meta-analysis in future reviews.

The distributional effects of tobacco tax increases across regions in Mexico: an extended cost-effectiveness analysis

BACKGROUND

Several studies have shown the beneficial effects of tobacco fiscal policy, but distributional effects have been less examined, especially at the subnational level. The objective of this study is to analyse the distributional effects of a one-peso tobacco tax increase (roughly equivalent to tripling the current excise tax) on health, poverty, and financial outcomes at the subnational level in Mexico.

METHODS

We employ an extended cost-effectiveness analysis that estimates life-years gained, smoking attributable deaths averted, treatment costs averted, number of persons avoiding poverty and catastrophic health expenditures, and additional tax revenues by income group across five regions.

RESULTS

With the one-peso tax increase (or 44% price increase), about 1.5 million smokers would quit smoking across the five regions, resulting in nearly 630 thousand premature deaths averted and 12.6 million life years gained. The bottom income quintile would gain three times more life years gains than the top quintile (ratio 3:1), and the largest gain for the most deprived would occur in the South (ratio 19:1), the region with the highest poverty incidence. Costs averted and additional tax revenues would reach 44.6 and 16.2 billion pesos, respectively. Moreover, 251 thousand individuals would avoid falling into poverty, including 53.2 in the lowest income quintile, and 563.9 thousand would avoid catastrophic health expenditures. Overall, the bottom income group would obtain 26% of the life years gained and 24% of the cost averted, while only paying 3% of the additional tax revenue.

CONCLUSIONS

The most significant gains from a substantial cigarette price increase would be for the poorest 20%, especially in the South, the most impoverished region of Mexico. Therefore, tobacco taxes are an opportunity for governments to advance in equity and towards the achievement of sustainable development goals on non-communicable diseases.

Participation in Physical Education Classes and Health-Related Behaviours among Adolescents from 67 Countries

The present study sought to examine the associations between participation in physical education (PE) classes and a range of health-related behaviours among adolescents. Secondary analysis of self-reported data from the Global Student Health Survey, collected between 2010 and 2017 from 222,121 adolescents (N = 117,914 girls; 49.0%; aged 13–17 years) from 67 countries and five world regions, was carried out. Participation in PE classes (0, 1–2, ≥3 days/week) was the independent variable. Physical activity (PA); sedentary behaviour (SB); active travel to school; fruit, vegetables, and alcohol consumption; and smoking; as well as adopting ≥5 of these healthy behaviours; were the dependent variables. Complex samples logistic regressions were performed to explore the associations between participation in PE classes and health-related behaviours. The results revealed that 18.2% of adolescents did not take part in PE classes. A total of 56.7% and 25.1% of adolescents reported participating in PE classes on 1–2 and ≥3 days/week, respectively. Only 26.8% of adolescents adopted ≥5 healthy behaviours. Participation in PE classes was positively associated with PA, active travel, fruit consumption, and vegetable consumption (only for ≥3 days/week), but was negatively associated with meeting SB recommendations, and with not smoking (only for girls and ≥3 days/week). Overall, PE participation was positively associated with adopting ≥5 healthy behaviours, with favourable results found for those who attended more PE classes. The findings revealed a positive association between participation in PE classes and a range of health-related behaviours among adolescents. This suggests that, worldwide, quality PE should be delivered at least 3 days per week up to daily to promote healthy lifestyles among adolescents.

Sugarcane Workweek Study: Risk Factors for Daily Changes in Creatinine

INTRODUCTION

Agricultural workers laboring in thermally stressful environments are at increased risk for kidney injury and chronic kidney disease of unknown origin (CKDu), and their environmental and occupational exposures have been considered to be important risk factors. This study examined the effects of repeated kidney stress from the simultaneous strain of work and other factors experienced by workers in Guatemala during a typical workweek.

METHODS

We collected data from 107 sugarcane workers across 7 consecutive work shifts. Data included information on daily occupational, meteorological, environmental, and lifestyle factors. We used multivariable linear mixed models to evaluate associations of these factors with percent change in creatinine.

RESULTS

We observed that increasing wet bulb globe temperature (β = 2.5%, 95% confidence interval [CI] = 0.3%, 4.7%) and increasing diastolic blood pressure (β = 6.2%, 95% CI = 0.9%, 11.6%) were associated with increases in creatinine across the shift, whereas consumption of water from chlorinated dormitory tanks as compared to artesian well water (β = -17.5%, 95% CI = -29.6%, -5.4%) and increasing number of rest breaks (β = -5.8%, 95% CI = -9.0%, -2.6%) were found to be protective against increases in creatinine. Workers reporting drinking tank water had lower concentrations of urine creatinine-corrected arsenic, lead, uranium, and glyphosate compared to workers reporting the use of well water or municipal water.

CONCLUSION

These results reinforce the need to focus on preventive actions that reduce kidney injury among this worker population, including strategies to reduce heat stress, managing blood pressure, and examining water sources of workers for nephrotoxic contaminants.

LifeFirst: Impact of a school-based tobacco and supari cessation intervention among adolescent students in Mumbai, India

INTRODUCTION

The youth are a vulnerable population-group for tobacco-related harms. Schools are an excellent setting for health promotion; yet there is a dearth of school-based cessation interventions, rarely evaluated for their impact. Here, we assess the impact of the LifeFirst program: an ongoing tobacco and supari (areca nut) cessation intervention delivered to students from corporation schools in Mumbai city.

METHODS

We used a prospective quasi-experimental design with an intervention and a control arm embedded within an ongoing LifeFirst program in select schools. We used a difference-in-difference analysis with baseline and end-line surveys to assess the program's impact on students' knowledge about harms, students' refusal skills, and prevalence of tobacco/supari use. We report our work using the TREND statement checklist.

RESULTS

A total of 959 students registered in the LifeFirst program. In our analysis, we included 827 students who completed both the baseline and end-line surveys. Postintervention, we found both tobacco and supari use reduced substantially among the intervention group while tobacco use increased among the control group. The difference-in-difference estimates show a statistically significant reduction of 17.9 and 38.1 percentage points in the intervention group for tobacco and supari use respectively, beyond the reduction in the control group.

CONCLUSIONS

The LifeFirst program was successful in reducing tobacco and supari use among the study participants and protected students in the intervention group against new uptake of tobacco. It helped improve knowledge score and refusal skills among students. Implementation and evaluation of similar school-based programs should be considered as part of a multi-strategy approach to reducing tobacco use among young people.

Factors Associated With the Differences Between Self-Report Smoking and Urinary Cotinine Criteria

During self-reporting, respondents underreport their smoking status for various reasons. We aimed to evaluate the difference between smoking status self-reporting and urinary cotinine tests in Korea respondents. Logistic regression analyses were performed to identify factors associated with the differences between self-reporting and urinary cotinine criteria. The dependent variable was the underreporting of smoking status; independent variables were sociodemographic, health status, and secondhand smoke (SHS) exposure. Total underreporting was 3.6% when Cot ≥164 and 4.0% when Cot-variable (classified) criteria underreported. Positive associations were found between smoking and age, education, drinking, and SHS. Underreporting in the nonsmoker group (odds ratio [OR] = 2.336; confidence interval [CI] = 1.717-3.179) was significantly associated with SHS, but this difference was nonsignificant in the ex-smoker group (OR = 1.184; CI = 0.879-1.638). Underreporting was 3.6% to 4.0%, and C-statistics was about 0.7, indicating that outcomes could be classified. SHS in nonsmokers was positively associated with underreporting; however, only the nonsmoker group had positive associations, demonstrating unintentional underreporting due to SHS.

A comparison of self-reported to cotinine-detected smoking status among adults in Georgia

BACKGROUND

Self-reported measures of tobacco use may have limited validity, particularly among some populations. This study aims to validate self-reported smoking measures among Georgian adults participating in the 2016 STEPS survey using cotinine biomarker measurements, and to explore potential differences according to sociodemographic characteristics. Additionally, this paper examines how the estimated prevalence of smoking in the population varies according to measurement type.

METHODS

Using the WHO standardized STEPS methodology, adults self-reported their smoking status. In a later stage of the survey, a subset of participants provided a urine sample, which was tested for cotinine. Using each participant's objective cotinine measurement and their self-reported smoking status, we calculated the sensitivity, specificity and positive predictive value of self-reported smoking. Next, we calculated the estimated prevalence of smokers according to the type of measurement.

RESULTS

Results indicated high sensitivity (83.37%, 95% CI: 76.79-88.37%) among males and relatively low sensitivity (38.60% CI: 29.23-48.90%) among females. According to self-report, the prevalence of smokers was 26.44% (23.61-29.48%), while according to cotinine detection, the prevalence of smokers was 32.27% (29.16-35.55%). Among all subgroups, the self-reported prevalence of smoking was significantly lower than the cotinine-detected prevalence.

CONCLUSIONS

To the best of our knowledge, this is the first time that the validity of the STEPS self-reported tobacco indicator has been tested. Self-reported measures of smoking status may lead to an under-estimation of smoking prevalence among Georgian adults, especially women. These findings suggest that integration of biochemical measures of smoking into tobacco use studies may be an important investment.

Changes over time in Lithuanian schoolchildren's attitudes toward addictive behaviors: Promoting and preventing factors

Background

Concern is growing about the high prevalence of traditional and new forms of addictive behaviors among young people due to the health risks and a better understanding of the factors causing these behaviors is needed.

Aim

To evaluate tendencies in the attitudes of Lithuanian schoolchildren toward addictive behaviors over a three year period and to ascertain the promoting and preventing factors of such behaviors.

Methods

The researchers developed a survey which was conducted twice over a three year period. The sample consisted of pupils in the 5^th, 9^th and 12^th grades (N = 1590, age range 11–19 years) from both urban and rural areas.

Results

Both the recognition of and involvement in addictive behaviors significantly increased with age. Motivation to abstain due to internal factors decreased with age and increased among pupils already involved in addictive behaviors. Time- and age-related differences were found regarding substance abuse and behavioral addictions. Whilst betting adverts were increasingly noticed over time, smoking adverts were decreasingly noticed over the three year period and it was concomitant with inconsistent changes in self-reported involvement in these behaviors.

Conclusions

Most significant changes in the attitudes of Lithuanian pupils toward addictive behaviors occur between the ages of 11 and 15 years. However, age-related changes differ for the pupils’ attitudes toward substance abuse and behavioral addictions. Increasing awareness of the potential risk of addictive behaviors does not prevent their increasing prevalence with age. Increased risk of involvement in addictive behavior correlates with decreased internal motivation to abstain from addictive behavior and decreased recognition of its potential risks. No clear correlation was found between significant changes in noticing adverts and involvement in addictive behaviors.

Discrepancy between Self-Reported and Urine Cotinine-Verified Environmental Tobacco Smoke Exposure among Rural Pregnant Women in China

Prenatal exposure to environmental tobacco smoke (ETS) is the most modifiable risk factor associated with adverse child-health outcomes. However, few longitudinal studies are implemented to compare the rates of discrepancy between self-reported (SR) and urinary cotinine (UC)-verified ETS exposure during the three trimesters of pregnancy, especially in rural areas. The objectives of this study were to assess the discrepancy between SR and UC-verified ETS exposure among rural women employing three measures throughout pregnancy, and to explore predictors related to these differences. This study used a prospective prenatal cohort consisting of 420 pregnant women whose ETS exposure was entirely evaluated by both SR and UC verification across three trimesters of pregnancy. Environmental tobacco exposure was assessed via SR verification, and was validated using the limit of detection for UC. The discrepancy rates were determined for each trimester. Multivariate logistic regression was used to assess the predictors associated with these differences. The discrepancy rates between SR and UC verification were 25.2%, 17.1%, and 20.5% (first, second, and third trimester, respectively). The highest inconsistency occurred in the first trimester. After adjusting for confounding factors, the following variables were found to have statistically significant associations with the discrepancy rate between SR and UC-verified ETS exposure: the number of smokers in the family and household income for all three trimesters, township site for the second and third trimester, and gravidity for the last trimester. The SR rate of ETS exposure among rural pregnant women is underreported, while the UC-verified rate is higher. More smokers in the family and gravidity may increase the risk of ETS exposure for pregnant women. Biochemical validation is warranted throughout pregnancy for the adoption of home-smoking bans and the promotion of community-based smoke-free programs.

Underestimation of Self-Reported Smoking Prevalence in Korean Adolescents: Evidence from Gold Standard by Combined Method

The objective of this study was to evaluate the validity of self-reported smoking prevalence in Korean adolescents by using an improved gold standard by a combined method. Using a stratified sampling method, we selected 13 schools from among 397 high schools that participated in the 2015 Korean Youth Health Risk Behavior Web-Based Survey (KYRBS). A second survey (repeated self-reporting questionnaire and urinary cotinine test) was conducted on 1058 students who completed the KYRBS. The gold standard of current smoker was defined as those either self-reporting as a smoker in the second survey or having a urinary cotinine concentration ≥50 ng/mL. The current smoking prevalence in the first survey (KYRBS) was 7.9% (boys 16.5% and girls 1.8%), which was lower than the results based on gold standard (11.3% total, boys 21.9% and girls 3.7%). The sensitivity and specificity of self-reported smoking status was 62.5% and 99.0%, respectively. In particular, the sensitivity of girls (43.5%) was lower than that of boys (67.0%). The self-reported smoking prevalence in Korean adolescents was underestimated, particularly among girls. Careful attention should be paid to interpreting adolescents’ smoking prevalence, and supplementary surveys or periodic validity tests need to be considered in Asian countries.

Environmental Tobacco Exposure and Urinary Cotinine Levels in Smoking and Nonsmoking Adolescents

Objective

We aimed to evaluate the association between environmental tobacco smoke (ETS) exposure and urinary cotinine levels in current adolescent smokers and nonsmokers. The secondary objective was to explore the association between ETS exposure and nicotine dependence in adolescent smokers.

Methods

Using the results from a validation study for the 2012 Global Youth Tobacco Survey in Mexico, we quantified urinary cotinine levels in adolescent smokers and nonsmokers. We fitted a multivariate regression model to assess the association between household exposure to ETS and cotinine levels in adolescent smokers and nonsmokers. In addition, using the questionnaire's answers for morning cravings, we fitted a multivariate Poisson regression model to explore the association between household ETS exposure and nicotine dependence in adolescent smokers.

Results

For each day of household ETS exposure, cotinine levels increase by 5% in adolescent smokers compared to a 2% increase in nonsmokers, adjusting for the number of cigarettes smoked per week, age and sex (exp(β) 1.05; 95% confidence interval [CI] [1.00, 1.10]; p = .041). Morning cravings increase 11% for each day of household ETS exposure adjusting for the number of cigarettes smoked per week, age and sex (prevalence ratio [PR] 1.11; 95% CI [0.99, 1.25]; p = .064).

Conclusions

There is an association between ETS exposure and cotinine levels, and ETS may contribute to nicotine dependence in adolescent smokers. If confirmed, avoiding ETS exposure could prove helpful for addiction control and quitting in adolescents.

Implications

Evidence suggests that ETS increases cotinine levels in nonsmokers and adult smokers. However, no study has explored the association between ETS exposure and cotinine levels and addiction in adolescent smokers. This paper provides evidence of an association between ETS exposure and cotinine levels in adolescent smokers: each day of environmental tobacco smoke exposure at home increased cotinine levels by 5% among smokers. In addition, morning cravings in adolescent smokers increased 11% for every day of ETS exposure. ETS exposure is a significant source of nicotine for adolescent smokers and could play an important role in addiction.

The Role of Maternal Adverse Childhood Experiences and Race in Intergenerational High-Risk Smoking Behaviors

INTRODUCTION

A history of adversity in childhood is associated with cigarette smoking in adulthood, but there is less evidence for prenatal and next-generation offspring smoking. We investigated the association between maternal history of childhood adversity, pregnancy smoking, and early initiation of smoking in offspring, overall and by maternal race/ethnicity.

METHODS

Data on maternal childhood exposure to physical abuse, household alcohol abuse, and household mental illness, prenatal smoking behaviors, and offspring age of smoking initiation were analyzed from the US National Longitudinal Survey of Youth 1979 (NLSY79, n = 2999 mothers) and the NLSY79 Children and Young Adults Survey (NLSYCYA, n = 6596 children). Adjusted risk ratios were estimated using log-linear regression models. We assessed multiplicative interaction by race/ethnicity for all associations and a three-way interaction by maternal exposure to adversity and race/ethnicity for the association between prenatal and child smoking.

RESULTS

Maternal exposure to childhood physical abuse was significantly associated with 39% and 20% increased risks of prenatal smoking and child smoking, respectively. Household alcohol abuse was associated with significantly increased risks of 20% for prenatal smoking and 17% for child smoking. The prenatal smoking-child smoking relationship was modified by maternal exposure to household alcohol abuse and race. There were increased risks for Hispanic and white/other mothers as compared to the lowest risk group: black mothers who did not experience childhood household alcohol abuse.

CONCLUSIONS

Mothers in this national sample who experienced adversity in childhood are more likely to smoke during pregnancy and their offspring are more likely to initiate smoking before age 18. Findings varied by type of adversity and race/ethnicity.

IMPLICATIONS

These findings support the importance of a life-course approach to understanding prenatal and intergenerational smoking, and suggest that maternal early-life history is a potentially important risk factor that could be targeted with screening and interventions to reduce smoking in pregnant women and their children.

Tobacco use and second-hand smoke exposure in young adolescents aged 12-15 years: data from 68 low-income and middle-income countries

BACKGROUND

Tobacco use is an important risk factor for non-communicable diseases worldwide. However, the global extent and prevalence of tobacco use in adolescents is poorly described. Using previously collected survey data, we aimed to assess tobacco use and second-hand smoke exposure in young adolescents aged 12-15 years in 68 low-income and middle-income countries.

METHODS

We used data from the Global School-based Student Health Survey (2006-13) and the China Global Tobacco Youth Survey (2013), which are school-based surveys of young adolescents aged 12-15 years that assess health behaviours using a standardised, anonymous, self-reported questionnaire. We calculated the prevalence of current tobacco use and exposure to second-hand smoke in young adolescents from 68 low-income and middle-income countries that collected these data in the surveys. We used a multilevel model to estimate the association between parental tobacco use, second-hand smoke, and adolescent tobacco use, adjusting for sex, age, school, school class, country's purchasing power parity, smoking initiation age, national prevalence of tobacco use among adults, year the WHO FCTC was ratified for each country, proxy of socioeconomic status, and survey year.

FINDINGS

The mean prevalence of current tobacco use was 13·6%, ranging from 2·8% in Tajikistan to 44·7% in Samoa. In most countries, the prevalence of tobacco use was higher for boys than girls, and higher for adolescents aged 14-15 years than for those aged 12-13 years. The overall prevalence of second-hand smoke exposure was 55·9%, ranging from 16·4% in Tajikistan to 85·4% in Indonesia. Parental tobacco use (as reported by the young adolescents), especially maternal use, was associated with tobacco use in young adolescents (odds ratio 2·06, 95% CI 1·93-2·19, for maternal and 1·29, 1·23-1·35 for paternal use). Second-hand smoke exposure was also a risk factor for young adolescents' tobacco use (2·56, 2·43-2·69). However, the prevalence of tobacco use was not associated with a country's purchasing power parity.

INTERPRETATION

Tobacco use and second-hand smoke exposure were frequent among young adolescents aged 12-15 years in low-income and middle-income countries. Parental tobacco use and second-hand smoke exposure were strongly associated with young adolescents' tobacco use. The data emphasise the need to strengthen tobacco control interventions and programmes in young adolescents from low-income and middle-income countries.

FUNDING

This work was partly supported by the Young Scholars Program of Shandong University (2015WLJH51), the Shandong Provincial Natural Science Foundation (ZR2012HQ033), and the National Natural Science Foundation (81302496).