Advertising Exposure From Online and Offline Sources and Youth Tobacco Use: Findings From the Adolescents, Place, and Behavior Study.

INTRODUCTION: Tobacco use among adolescents is an ongoing public health concern. Youth tobacco use has been associated with advertising, from both online sources and retail environments. AIMS AND METHODS: This study examined associations between exposure to tobacco advertisements from tobacco retail outlets (TROs), internet, and social media sources and ever tobacco use among adolescents. Data were obtained from youth, aged 11-17 years (N = 401) from Richmond, VA. Bayesian index and group index models were fitted to estimate indices of exposure to (1) social media use, (2) tobacco ads on social media, and (3) TRO store visits and their association with ever tobacco use. The most important components of the exposure indices were also determined based on the index component weights from the Bayesian index models. RESULTS: In Bayesian index models of single exposures, each exposure index was significantly associated with tobacco use. In the best-fitting model, social media tobacco ads (odds ratio [OR] = 2.2; 95% credible interval [CI]: 1.2, 4.5) and TRO store visits (OR = 1.6; 95% CI: 1.1, 2.3) were significantly associated with ever tobacco use, as was older age (OR = 1.4; 95% CI: 1.2, 1.8). Index component weights revealed Snapchat ad frequency as the most important platform in the social media index and convenience stores as the most important type of store in the TRO index. CONCLUSIONS: Exposure to pro-tobacco advertisements on social media and visits to TROs are associated with adolescent ever tobacco use. Results provide support for policies that would restrict the promotion of tobacco products at TROs and on social media. Tobacco regulations and interventions targeting convenience stores and Snapchat may be warranted to reduce youth tobacco use. IMPLICATIONS: Current evidence provide support for policies that would restrict the promotion of tobacco products at TROs and on social media. Findings suggest that regulations and interventions that specifically target advertisements in convenience stores and on Snapchat may be currently warranted to reduce youth tobacco use.

Tobacco and Nicotine Product Use Transitions by Race and Ethnicity: Results from a Latent Transition Analysis Using Data from the Truth Longitudinal Cohort (2020-2022).

OBJECTIVE: To examine use and frequency patterns across e-cigarettes, cigarettes, and little cigars, cigars, and cigarillos (LCCs) over time and determine whether patterns differ by race and ethnicity. METHODS: Data was obtained from the Truth Longitudinal Cohort of youth and young adults between September 2020 and June 2022. Latent class and transition analyses were used to classify participants (N = 4448) into subgroups, based on frequency of tobacco product use in the past 30 days, and to estimate the probability of use pattern transitions by race and ethnicity, adjusted for the effects of gender, financial situation, parental education, household tobacco use, and sensation seeking. RESULTS: Four latent classes were identified: former/noncurrent users, predominantly frequent to daily (FTD) e-cigarette users, predominantly FTD e-cigarette and LCC users, and predominantly FTD cigarette with polytobacco users. Use trajectories differed by race and ethnicity. A lower proportion of those who identified as non-Hispanic Black (60.0%) remained e-cigarette and LCC users, relative to those who identified as non-Hispanic White (86.0%), Hispanic or Latino (86.0%), and another race and ethnicity (79.0%). A lower proportion of those who identified as Hispanic or Latino (54.0%) and another race and ethnicity (59.9%) remained cigarette with polytobacco users, relative to those who identified as non-Hispanic White (76.0%) and non-Hispanic Black (72.0%). A greater proportion of non-Hispanic Black respondents transitioned from e-cigarette and LCC user to former/noncurrent user (40.0%) and polytobacco user to e-cigarette and LCC user (11.0%), relative to other racial/ethnic groups. CONCLUSION: More research is needed to determine why tobacco use trajectories differ by race and ethnicity. Such research will be important in informing comprehensive approaches that promote evidence-based prevention policies and programs.

Electronic Cigarette Nicotine Flux, Nicotine Yield, and Particulate Matter Emissions: Impact of Device and Liquid Heterogeneity.

INTRODUCTION: Electronic cigarettes (ECIGs) heat a nicotine-containing liquid to produce an inhalable aerosol. ECIG power (wattage) and liquid nicotine concentration are two factors that predict nicotine emission rate ("flux"). These factors can vary greatly across devices and users. AIMS AND METHODS: The purpose of this study was to examine ECIG device and liquid heterogeneity in "real world" settings and the association with predicted nicotine flux, nicotine yield, and total particulate matter (TPM) emissions. Past 30-day ECIG users (n = 84; mean age = 23.8 years [SD = 9.6]) reported device and liquid characteristics. Device power was measured via multimeter, device display screens, or obtained via labeling. Liquid nicotine concentration was obtained via labeling or through chemical analysis. Predicted nicotine flux, nicotine yield, and TPM associated with 10 4-second puffs were calculated for participants' primary devices. RESULTS: Participants' primary devices were box mods (42.9%), disposable vapes (20.2%), and pod mods (36.9%). Most participants (65.5%) reported not knowing their primary device wattage. Rebuildable/box mods had the greatest power range (11.1-120.0 W); pod mod power also varied considerably (4.1-21.7 W). Unlike device wattage, most participants (95.2%) reported knowing their liquid nicotine concentration, which ranged from 3.0 to 86.9 mg/ml (M = 36.0, SD = 29.3). Predicted nicotine flux varied greatly across products (range =12.0-160.1 µg/s, M = 85.6 µg/s, SD = 34.3). Box mods had the greatest variability in wattage and predicted nicotine flux, nicotine yield, and TPM yield. CONCLUSIONS: ECIG device and liquid heterogeneity influence nicotine and other toxicant emissions. Better measurement of ECIG device and liquid characteristics is needed to understand nicotine and toxicant emissions and to inform regulatory policy. IMPLICATIONS: ECIG device and liquid heterogeneity cause great variability in nicotine flux and toxicants emitted. These data demonstrate the need to examine device and liquid characteristics to develop empirically informed, health-promoting regulatory policies. Policies may include setting product standards such that ECIG products cannot (1) have nicotine fluxes much greater than that of a cigarette to decrease the risk of dependence, (2) have nicotine fluxes that are very low and thus would have minimal appeal to cigarette smokers and may serve as starter products for youth or nontobacco users, and (3) emit large amounts of particulate matter and other toxicants.

Relative increases in direct-to-consumer menthol ads following 2020 FDA guidance on flavoured e-cigarettes.

OBJECTIVE: To examine potential changes in email and direct mail advertisements for flavoured e-cigarettes following the 2020 Food and Drug Administration (FDA) flavour guidance. METHODS: Digital copies of e-cigarette advertisements were obtained from Mintel Comperemedia (November 2019-May 2020) and coded for the presence of flavours. Χ2 tests were used to determine changes in the prevalence of email and direct mail advertisements for e-cigarettes with menthol, non-menthol and no flavours. RESULTS: Following FDA guidance, the relative proportion of menthol-flavoured e-cigarette advertisements sent via email significantly increased from 22.5% to 52.2%. No changes were found for e-cigarette advertisements mentioning no flavours, nor non-menthol-flavoured e-cigarettes, sent via email or direct mail. CONCLUSIONS: The 2020 FDA flavour guidance was followed by an increased proportion of direct-to-consumer email advertisements of menthol-flavoured e-cigarette products.

E-cigarette Device Type, Source, and Use Behaviors of Youth and Young Adults: Findings from the Truth Longitudinal Cohort (2020-2021).

Background: E-cigarette device types vary in the amount of nicotine delivered to users. Given that youth and young adults are using pod-based and disposable e-cigarettes with high nicotine concentrations, it is important to determine how e-cigarette use behaviors associated with nicotine dependence may differ across e-cigarette device type. Methods: Baseline information was collected from September 2020 to March 2021 and follow-up information was collected from July to October 2021 from the Truth Longitudinal Cohort. The final analytic sample included respondents (aged 15-24) who reported current use of e-cigarettes at either baseline or follow-up and provided information on the 4-item E-cigarette Dependence Scale (EDS). Differences in endorsement of items from the EDS by e-cigarette device type (pod-based, disposable, or tank) were assessed using chi-square tests. Results: Participants (N = 308) were evenly split on age (15-20, 21+) and gender. Most 15-20-year-olds used disposable e-cigarettes, while those 21+ years primarily used tank devices. Although EDS score did not differ by e-cigarette device type, positive endorsement of two items from the EDS significantly differed by e-cigarette device type. More tank users endorsed reaching for a device without thinking about it (tank: 92.6%; pod-based: 79.0%; disposables: 79.9%, p = 0.04) and vaping more before going into a situation where vaping is not allowed (tank: 92.9%; pod-based: 71.0%; disposables: 73.0%, p < 0.01). Conclusions: Findings have the potential to inform policy implementation by providing evidence for specific targets for regulatory action that can help to reduce the burdens of e-cigarette use among youth and young adults, as results suggest that tank device users are more likely to endorse use behaviors associated with nicotine dependence.

Vaping-Know the Truth: Evaluation of an Online Vaping Prevention Curriculum.

BACKGROUND: Unacceptably high levels of e-cigarette use among youth paired with growing research about the dangers of vaping demonstrate a critical need to develop interventions that educate young people to reject e-cigarette use and promote cessation for current users. Vaping: Know the Truth (VKT) is a free digital learning experience prioritizing middle and high school students that aims to improve students' knowledge about the dangers of using e-cigarettes and provide quitting resources for those who already vape. The current study was designed to evaluate whether students receiving the curriculum increased knowledge of the dangers of vaping. METHODS: The outcome measures were calculated as the change in the number of correct responses from the pre- to post-module assessments among middle and high school students who completed four modules of the VKT curriculum (N = 103,522). Linear regression was performed to determine the association between the student's pre-module assessment score and the knowledge change score after completion of the four modules. RESULTS: Students' e-cigarette knowledge significantly improved by an average of 3.24 points (SD: 3.54), following implementation of the VKT curriculum. This indicates that participants answered more than 3 additional questions correctly, on average, after the intervention. CONCLUSION: Findings demonstrate that the Vaping: Know the Truth curriculum is an effective resource for increasing knowledge among youth about the harms associated with e-cigarette use. Further research is needed to evaluate whether the intervention is associated with behavioral outcomes over time.

The Association Between Health Literacy and Tobacco Use: Results from a Nationally Representative Survey.

Dual use of conventional cigarettes and electronic cigarettes presents an emerging public health issue. Previous research has demonstrated a negative relationship between health literacy and conventional cigarette (CIG) use. However, the relationship between health literacy and e-cigarette (ECIG) use remains unclear. This studies examines the possible association of health literacy and CIG, ECIG, or dual use. A multinomial regression was used to model the association between health literacy and current CIG use, current ECIG use, or dual tobacco use status using state-optional data from the 2016 Behavioral Risk Factor Surveillance System (BRFSS; N = 40,404). One-third of the sample (N = 13,478; 33.3%) had initiated tobacco use. Approximately 36.6% of participants exclusively used cigarettes. A smaller proportion of participants were dual users of ECIG and CIGs (7.0%) and e-cigarette exclusive users (4.5%). After adjusting for covariates, higher levels of oral health literacy was associated with lower odds of current dual use. However, there was no significant association between written HL and either conventional cigarette use or electronic cigarette use or after adjusting for covariates. Oral messaging around the dangers of CIG use may be effective at lowering odds of CIG or dual use, especially for those with higher levels of HL. Further research is needed to examine how to best disseminate information regarding the health risks of ECIGs.

Transitions in Frequent to Daily Tobacco and Nicotine Use among Youth and Young Adults.

Objective: To examine use and frequency patterns across e-cigarettes, cigarettes, and little cigars, cigarillos, and cigars (LCCs) over time. Methods: Data were obtained from the Truth Longitudinal Cohort (TLC), a nationally representative longitudinal cohort of youth and young adults. Latent class analysis was conducted to classify participants (n = 5274) into subgroups based upon frequency of use of cigarettes, e-cigarettes, and little cigars, cigarillos, and cigars (LCCs) in the past 30 days. Latent transition analysis was used to estimate the probability of use pattern transitions across 23 months (February 2018 to December 2019), adjusted for the effects of gender, race/ethnicity, financial situation, sensation seeking, parent education, and household smoking. Findings: Findings reveal four groups of tobacco product users: (1) frequent to daily cigarette users (9%), (2) frequent to daily cigarette and LCC users (3%), (3) frequent to daily e-cigarette users (10%), and (4) former or noncurrent tobacco users (78%). Although most respondents (69-94%) retained their initial user patterns during the observation period, results also indicate shifts between user groups. Notably, 14% of frequent to daily cigarette and LCC users transitioned to frequent to daily cigarette use, while 6% of frequent to daily cigarette and LCC users, 9% of frequent to daily cigarette users, and 4% of former or noncurrent tobacco users transitioned to frequent to daily e-cigarette use. Conclusion: Although most frequent to daily tobacco users stay with their primary product, there are transitions between frequent to daily cigarette, e-cigarette, and LCC use. Transition patterns may influence risk for nicotine addiction among youth and young adults. Thus, policies focused on preventing and reducing all tobacco use are needed to curb the risk of nicotine addiction among youth and young adults.

Influence of Flavors and Nicotine Concentration on Nicotine Dependence in Adolescent and Young Adult E-Cigarette Users.

Objective: The objective of this study is to examine the relationships between e-cigarette flavors, nicotine concentration, and their interaction on measures of nicotine dependence.Methods: Survey data are drawn from a cross-sectional convenience sample of past 30-day e-cigarette users aged 15 to 24 years (N = 2037) collected between October 2020 and November 2020. Participants were asked to provide information about the e-cigarette products they used most regularly. Only those with available information on flavors (fruit, mint, menthol/ice, and tobacco), nicotine concentration (0-2.9%, 3-4.9%, and 5% or greater), and time to first vape after waking (within 30 minutes, greater than 30 minutes) were included in analyses (N = 1430). Generalized linear regression models were used with log link and binary distribution to assess the relationship between flavors, nicotine concentration, and nicotine dependence. Effect modification by nicotine concentration was assessed using an interaction term for flavors by nicotine concentration. Models were adjusted for age, race/ethnicity, gender, and financial situation.Findings: Fruit, mint, and menthol flavor user groups had a very similar dose-response relationship between nicotine concentration and prevalence of vaping within 30 minutes. These groups showed that the prevalence of vaping within 30 minutes gradually increased as nicotine concentration increased. Meanwhile, tobacco flavor user groups demonstrated a decrease in prevalence of vaping within 30 minutes, as nicotine concentration increased.Conclusion: Results highlight the need for understanding how e-cigarette product characteristics like flavors and nicotine concentration can facilitate nicotine dependence to e-cigarettes. Findings suggest that comprehensive e-cigarette product regulation of all flavors and reducing nicotine concentration will help to reduce the risk for nicotine dependence among young people.

Cannabis use among cancer survivors in the United States: Analysis of a nationally representative sample.

BACKGROUND: Research on cannabis use among those with a history of cancer is limited. METHODS: Prevalence of past-year cannabis use among individuals with and without a cancer history and predictors of use within these 2 groups were determined using data from the Population Assessment of Tobacco and Health study, a nationally representative, longitudinal survey conducted in the United States (waves 1-4; 2013-2018). Discrete time survival analyses were used to estimate baseline (wave 1) predictors (physical health status, mental health status, pain, and demographic variables) on past-year engagement with cannabis within individuals who reported a cancer diagnosis at wave 1 (n = 1022) and individuals who reported never having cancer at any wave (n = 19,702). RESULTS: At the most recent survey, 8% of cancer survivors reported past-year cannabis use, compared with 15% of those without a cancer history. Across 4 time points, an estimated 3.8% of cancer survivors engaged with cannabis, as compared to 6.5% of those without a cancer history. Across both groups, older age and having health insurance were associated with lower likelihood of engaging in cannabis use, whereas greater levels of pain were associated with higher likelihood of engaging in cannabis use. Among those without a cancer history, being female, White, and having better mental health status were associated with lower likelihood of engaging in cannabis use. CONCLUSIONS: Although cannabis use prevalence is lower among cancer survivors, the reasons for use are not markedly different from those without a cancer history. Continued monitoring of use, reasons for use, and harms or benefits is warranted. LAY SUMMARY: Results from this study, which uses data from the Population Assessment of Tobacco and Health Study, indicate that cannabis use is generally increasing across cancer survivors and those without a history of cancer. Cancer survivors are using cannabis at slightly lower rates than those without a history of cancer. Factors related to pain seem to be more prevalent in cancer populations relative to the general population, and could be contributing to cannabis use within cancer survivor populations.

Identifying the Best Questions for Rapid Screening of Secondhand Smoke Exposure Among Children.

INTRODUCTION: Many children suffer from secondhand smoke exposure (SHSe), which leads to a variety of negative health consequences. However, there is no consensus on how clinicians can best query parents for possible SHSe among children. We employed a data-driven approach to create an efficient screening tool for clinicians to quickly and correctly identify children at risk for SHSe. METHODS: Survey data from mothers and biospecimens from children were ascertained from the Neurodevelopment and Improving Children's Health following Environmental Tobacco Smoke Exposure (NICHES) study. Included were mothers and their children whose saliva were assayed for cotinine (n = 351 pairs, mean child age = 5.6 years). Elastic net regression predicting SHSe, as indicated from cotinine concentration, was conducted on available smoking-related questions and cross-validated with 2015-2016 National Health and Nutrition Examination Survey (NHANES) data to select the most predictive items of SHSe among children (n = 1670, mean child age = 8.4 years). RESULTS: Answering positively to at least one of the two final items ("During the past 30 days, did you smoke cigarettes at all?" and "Has anyone, including yourself, smoked tobacco in your home in the past 7 days?") showed area under the curve = .82, and good specificity (.88) and sensitivity (.74). These results were validated with similar items in the nationally representative NHANES sample, area under the curve = .82, specificity = .78, and sensitivity = .77. CONCLUSIONS: Our data-driven approach identified and validated two items that may be useful as a screening tool for a speedy and accurate assessment of SHSe among children. IMPLICATIONS: The current study used a rigorous data-driven approach to identify questions that could reliably predict SHSe among children. Using saliva cotinine concentration levels as a gold standard for determining SHSe, our analysis employing elastic net regression identified two questions that served as good classifier for distinguishing children who might be at risk for SHSe. The two items that we validated in the current study can be readily used by clinicians, such as pediatricians, as part of screening procedures to quickly identify whether children might be at risk for SHSe.

Effect of Prenatal Smoke Exposure on Birth Weight: The Moderating Role of Maternal Depressive Symptoms.

INTRODUCTION: Both prenatal smoke exposure and depression have been linked to lower birth weight, a risk factor for morbidity and mortality. Few studies have looked at the interaction between these risk factors and none have used a biomarker to objectively measure prenatal smoke exposure. The current study sought to examine independent and interactive effects of cotinine and depression on birth weight. The effect of race was also explored. METHOD: Data were drawn from a prospective study of pregnant women (N = 568) in the southeastern United States. Maternal demographic, health information, depressive symptoms, and birth data were collected via self-report and medical record abstraction. Prenatal blood samples were assayed for cotinine. RESULTS: Controlling for covariates, multiple regression analyses indicated that both cotinine and depressive symptoms independently predicted lower birth weight and a significant interaction was also observed. Upon probing the interaction, a negative association between cotinine levels and birth weight was found in the context of higher depression but not lower depression scores. Similarly, logistic regression analyses revealed a significant interaction between cotinine and depression, such that cotinine predicted having a baby less than 2500 g among women who fell above the indicated cutoff score. African American women had the highest levels of cotinine and lowest weight babies; however, race was not a significant moderator. CONCLUSIONS: Results suggest prenatal smoke exposure has a greater negative effect on birth weight for women endorsing co-occurring depressive symptoms. Findings can inform targeted interventions and assist medical providers with identifying women at increased risk for poor perinatal outcomes. IMPLICATIONS: Despite the common occurrence of smoking during pregnancy and prenatal depression, the interaction between these risk factors on birth weight has rarely been examined. Further, the extant results have been mixed, likely due in part to difficulties in measurement. The current study was the first to use prenatal cotinine to assess bias-free, continuous levels of prenatal smoke exposure. Results indicate that prenatal cotinine was a significant predictor of birth weight only in the context of maternal depressive symptoms. These findings have important implications for mitigating negative perinatal outcomes for pregnant women and their children.

Determinants of Youth-Reported Past 30-Day Tobacco Use.

The objective of this study was to utilize cross-sectional surveys to identify factors associated with past 30-day tobacco use among a sample youth and to determine whether regional differences exist. Data were obtained from the Virginia Youth Survey (2015 and 2017). Multinomial logistic regression models were used to examine associations between measures of past 30-day tobacco use and region, sex, grade, race/ethnicity, tobacco advertisement exposure, and presence of tobacco-free policies in the home and personal vehicles. These correlates were selected based upon existing literature on youth tobacco use. Past 30-day cigarette use, combustible tobacco use, non-combustible tobacco use, and dual product use were associated with region, sex, grade, and race/ethnicity. Specifically, youth residing in the Southwestern region of the state, males, and non-Hispanic White students and youth of other race/ethnicity were more likely to report past 30-day tobacco use. Additionally, higher levels of exposure to tobacco advertisements was also associated with past 30-day tobacco use. Future research needs to investigate the mechanisms by which youth tobacco use may differ by region, to help guide and target future policy and programming related to tobacco prevention and control at the local level.

Student Attitudes Toward Tobacco Use and Tobacco Policies on College Campuses.

We utilized a mixed methods approach to assess student attitudes towards tobacco use and campus tobacco policies. Interviews (N = 21), focus groups (N = 2 groups, 4-5 participants each), and an online survey (N = 636) were conducted among a sample of students attending a 4-year, urban, public university in the Mid-Atlantic region of the United States. In interviews and focus groups, students expressed skepticism about a tobacco-free campus policy due to perceived violations of personal rights and challenges with enforcement. Of the sample surveyed, 9.2% and 20.6% had used cigarettes or e-cigarettes within the past 30 days. The majority of students agreed that colleges have a responsibility to adopt tobacco-free policies that reduce the risk of tobacco addiction (62.4%) and ensure smoke-free air to breathe (81.5%). However, more than half (56.3%) also indicated that a policy allowing for designated smoking areas for cigarettes was best for campus, which runs counter to a comprehensive tobacco-free policy. Academic year, gender, and race/ethnicity were significant factors associated with support for tobacco-free policies. Current smokers and vapers were less likely to support tobacco-free policies that reduce the risk of tobacco addiction (OR = 0.3, 95% CI 0.1, 0.7 for smokers; OR = 0.3, 95% CI 0.1, 0.6 for vapers), but not policies that ensure smoke-free air to breathe. E-cigarettes pose a unique obstacle to tobacco-free policies, as students perceived e-cigarettes to be less harmful than cigarettes. To implement a tobacco-free campus policy, students suggested educational campaigns that focus on the potential health benefits of a tobacco-free campus.

Perceived harms of and exposure to tobacco use and current tobacco use among reproductive-aged women from the PATH study.

Data for this study were obtained from reproductive-aged women (aged 18-44 years, at wave 1) from waves 1 (2013-2014) and 2 (2014-2015) of the Population Assessment of Tobacco and Health Study (n = 13,241). Bivariate and multinomial regression analyses were performed associating past 30-day use of cigarettes only, e-cigarettes only, and dual use with perceptions of harm, exposure to tobacco product use, and sociodemographic variables. Cross-sectional and longitudinal analyses were conducted. Of all reproductive-aged women included in the analyses, 75.5 percent reported no tobacco use, 16.9 percent reported cigarette use only, 1.5 percent reported e-cigarette use only, and 6.1 percent reported dual use within the past 30 days. Perceived harm, tobacco exposure, pregnancy status, age, race/ethnicity, income, education, and sexual orientation were associated with the past 30-day use, cross-sectionally at wave 1. Similar associations were found for longitudinal analyses using wave 2 data, except for income and education, which were no longer associated. The results of this study contribute to knowledge regarding the prevalence and correlates of tobacco use across exclusive cigarette, exclusive e-cigarette, and dual use among reproductive-aged women.

The role of genetic and environmental influences on the association between childhood ADHD symptoms and BMI.

BACKGROUND/OBJECTIVES: Although childhood attention deficit hyperactivity disorder (ADHD) has been previously associated with concurrent and later obesity in adulthood, the etiology of this association remains unclear. The objective of this study is to determine the shared genetic effects of ADHD symptoms and BMI in a large sample of sibling pairs, consider how these shared effects may vary over time, and examine potential sex differences. SUBJECT/METHODS: Sibling pair data were obtained from the National Longitudinal Study of Adolescent to Adult Health (Add Health); childhood ADHD symptoms were reported retrospectively during young adulthood, while three prospective measurements of BMI were available from young adulthood to later adulthood. Cholesky decomposition models were fit to this data using Mx and maximum-likelihood estimation. The twin and sibling sample for these analyses included: 221 monozygotic (MZ) pairs (92 male-male, 139 female-female), 228 dizygotic (DZ) pairs (123 male-male, 105 female-female), 471 full-sibling (FS) pairs (289 male-male, 182 female-female), 106 male-female DZ twin pairs, and 234 male-female FS pairs. RESULTS: The magnitude of the association between childhood ADHD symptoms and BMI changed over time and by sex. The etiological relationship between childhood ADHD symptoms and the three prospective measurements of BMI differed for males and females, such that unique or non-shared environmental influences contributed to the relationship within males and genetic factors contributed to the relationship within females. Specifically, among females, genetic influences on childhood ADHD symptoms were partially shared with those effecting BMI and increased from adolescence to later adulthood (genetic correlation = 0.20 (95% CI: 0.07-0.36) in adolescence and 0.24 (95% CI: 0.10, 0.41) in adulthood). CONCLUSION: Genetic influences on ADHD symptoms in childhood are partially shared with those effecting obesity. However, future research is needed to determine why this association is limited to females.

Associations between maternal cytokine levels during gestation and measures of child cognitive abilities and executive functioning.

Preclinical studies demonstrate that environmentally-induced alterations in inflammatory cytokines generated by the maternal and fetal immune system can significantly impact fetal brain development. Yet, the relationship between maternal cytokines during gestation and later cognitive ability and executive function remains understudied. Children (n = 246) were born of mothers enrolled in the Newborn Epigenetic Study - a prospective pre-birth cohort in the Southeastern US. We characterized seven cytokines [IL-1ß, IL-4,IL-6, IL-12p70, IL-17A, tumor necrosis factor-α (TNFα), and interferon-γ (IFNγ)] and one chemokine (IL-8) from maternal plasma collected during pregnancy. We assessed children's cognitive abilities and executive functioning at a mean age of 4.5 (SD = 1.1) years. Children's DAS-II and NIH toolbox scores were regressed on cytokines and the chemokine, controlling for maternal age, race, education, body mass index, IQ, parity, smoking status, delivery type, gestational weeks, and child birth weight and sex. Higher IL-12p70 (ßIL-12p70 = 4.26, p = 0.023) and IL-17A (ßIL-17A = 3.70, p = 0.042) levels were related to higher DAS-II GCA score, whereas higher IL-1ß (ßIL-1B = -6.07, p = 0.003) was related to lower GCA score. Higher IL-12p70 was related to higher performance on NIH toolbox measures of executive functions related to inhibitory control and attention (ßIL-12p70 = 5.20, p = 0.046) and cognitive flexibility (ßIL-12p70 = 5.10, p = 0.047). Results suggest that dysregulation in gestational immune activity are associated with child cognitive ability and executive functioning.

Replication of the Interaction of PRKG1 and Trauma Exposure on Alcohol Misuse in an Independent African American Sample.

In the present study, we sought to replicate recent findings of Polimanti et al. (2017), who conducted a genome-wide gene-by-environment interaction study (GEWIS) and identified a gene-by-trauma interaction that predicts alcohol misuse among African Americans.  Consistent with the findings published by Polimanti and colleagues, results of the current study demonstrated an interaction effect, b = 0.41, of trauma exposure and rs1729578 in the intron of PRKG1 on alcohol misuse in a subsample of ancestral African Americans. The minor allele (rs1729578*C) was positively associated with increased alcohol use disorder symptoms in trauma-exposed subjects and negatively associated in non-trauma-exposed subjects.  This effect, however, was only significant for one out of three alcohol outcome measures we investigated, suggesting the interaction may be most salient when predicting higher severity of alcohol misuse. Additionally, the effect did not remain significant after we accounted for testing the effect on three different outcome variables. Also in line with the original study, the gene-by-environment effect was not demonstrated among the ancestral European subsample.  The findings suggest this gene variant may increase an individual's susceptibility to environmental influences, both adverse and supportive.

Associations Between Initial Subjective Experiences with Tobacco and Self-Reported Recent Use in Young Adulthood.

BACKGROUND: Youth tobacco use behaviors are predictive of patterns in adulthood and effect long-term health outcomes. Yet, few studies have examined the effect of initial subjective experiences (ISEs) during first tobacco use, which has been found to be an indicator of individuals. sensitivity to nicotine and vulnerability to dependence. OBJECTIVE: The present study aimed to determine the prevalence of ISEs across a variety of tobacco products, evaluate the factor structure of ISEs by first tobacco product used, and examine the relationship between ISEs and recent (30-day) use of tobacco products across time, using a university sample. METHODS: Exploratory factor analyses were conducted to identify latent factors present with respect to items measuring ISEs with tobacco, separately by tobacco product (e.g. cigarettes, cigars, hookah, e-cigarettes). Factor scores for positive and negative ISEs were calculated. Multiple logistic regression analyses were conducted to examine associations between ISEs and recent use of each tobacco product, adjusted for age at first use, sex, race/ethnicity, and cohort. RESULTS: ISEs differ by the first tobacco product used. Associations between factor scores for positive and negative ISEs and recent use were found across a variety of tobacco products. Overall, positive ISEs were more strongly associated with recent use, relative to negative ISEs. CONCLUSIONS: Further research is needed to identify genetic and biological pathways and social contexts influencing initial subjective experiences with tobacco use, in efforts to delay the initiation for tobacco use and reduce risk for continued use among young adults.

Genotype × Environment Interaction in Smoking Behaviors: A Systematic Review.

INTRODUCTION: There has been rapid growth in research exploring gene-environment interaction (G×E) contributing to smoking behaviors. Yet, no systematic review exists to date. METHODS: This article aims to review evidence on the contribution of G×E to the risk of smoking. Through a search of electronic databases (ie, Google Scholar, PubMed, ScienceDirect, and Elsevier) up until May 2014, 16 studies of G×E focused on smoking behaviors were identified. These studies were compared in terms of: research design and sample studied, measure of smoking behavior and environments used, genes explored, and G×E in relation to these factors. RESULTS: Thirteen of 16 studies (81.2%) found at least one significant G×E association. Wide variation in analytic methods was found across studies, especially with respect to the phenotypes of interest, environmental measures used, and tests conducted to estimate G×E. Heterogeneity across studies made it difficult to compare findings and evaluate the strength of evidence for G×E. CONCLUSIONS: G×E research on smoking contains studies that are methodologically different, making it difficult to assess the current state of the evidence. To decrease heterogeneity, we offer recommendations related to: (1) choice of measurement for environmental variables, (2) testing and reporting of main and interaction effects, (3) treatment of covariates, (4) reporting gene-environment correlation, and (5) conducting sensitivity analyses and checking for scaling artifacts. Continued study is needed to identify mechanisms by which genes and environmental factors combine to influence smoking behaviors. IMPLICATIONS: No comprehensive review of G×E studies of smoking behavior has previously been published. The present article seeks to fill this gap by providing a comprehensive review of: how G×E has been defined, how twin and molecular genetic methodologies have been used to test for G×E, and which genes and environmental factors are associated with smoking behaviors. Variations in methodological approaches make it difficult to interpret and summarize findings, so recommendations for future research are provided as a means to more easily compare and replicate findings across studies.