Prevalence of smoking assessed biochemically in an urban public hospital: a rationale for routine cotinine screening

Temporal Dynamics of Smoking Urges: Investigating Morning Cravings, Nicotine Dependence, and Smoking Behaviors

BACKGROUND

Understanding the relationship between different dimensions of nicotine cravings and smoking behavior is crucial for addressing nicotine dependence. This study examined how morning cravings and past-week cravings relate to nicotine intake, as measured by salivary cotinine, and the mediating role of cigarettes per day (CPD) and time to first cigarette (TTFC).

METHODS

Data were obtained as part of the Pennsylvania Adult Smoking Study (PASS), a community-based study of adult smokers. Participants (N = 353) completed structured questionnaires assessing smoking behaviors, cravings, and nicotine dependence. Salivary cotinine levels were measured to assess nicotine intake. Regression and path analyses were conducted to evaluate associations among craving phenotypes, smoking behaviors, and nicotine intake.

RESULTS

Morning cravings were significantly associated with both TTFC (β = -0.62, p < 0.001) and CPD (β = 0.27, p = 0.001), while past-week cravings were associated only with CPD (β = 0.14, p = 0.01). TTFC and CPD were both predictors of cotinine levels (β = -0.33, p < 0.001 and β = 0.22, p < 0.001, respectively). The total standardized effect of morning cravings on cotinine was 0.27, significantly greater than the effect of past-week cravings (0.05). Path analysis indicated that the influence of morning cravings on cotinine was mediated through both TTFC and CPD, whereas past-week cravings affected cotinine only via CPD.

CONCLUSIONS

Morning cravings demonstrate a stronger association with nicotine intake than past-week cravings, primarily through their effect on TTFC and CPD. These findings highlight the importance of targeting morning cravings in smoking cessation interventions. Future research should explore the role of neurobiological mechanisms, such as cortisol dynamics, in shaping nicotine cravings and smoking behavior.

Structurally Guided Engineering of Flavin-dependent Nicotine Dehydrogenase

Nicotine is a toxic alkaloid found in tobacco leaves that contaminates the environment when the leaves are smoked. In the present study, developed an enzyme technology for nicotine biodegradation and addressed biodetection applications. Recombinant wild-type nicotine oxidase/dehydrogenase from Pseudomonas sp. HZN6 (Nox-WT) was overexpressed and purified to ensure homogeneity. Nox-WT was clearly classified as a flavin adenine dinucleotide (FAD)-containing dehydrogenase, which catalyzes rapid nicotine oxidation in its reductive half-reaction; however, its oxidative half-reaction with O2 was slow and was identified as the rate-limiting step. An imbalance in the rate between the two half-reactions limits the overall catalytic turnover of Nox-WT. According to kinetic behavior, incomplete flavin recovery and substrate inhibition were also identified as obstructed issues that limit the enzyme efficiency. Nox-WT engineering has been performed to address these problems. The modeled structure of Nox-WT was constructed using AlphaFold to design candidate residues for site-directed mutagenesis. Using systematic screening through rapid kinetic techniques, all the limitations were eliminated in the engineered triple mutated Nox-Y338F/H364V/W423H. The mutations at Y338F and H364V expanded the tunnel for O2 accessibility, resulting in 21-fold faster FAD oxidation by O2 in this mutant than in Nox-WT. Mutation at W423H disrupted the binding of nicotine; therefore, substrate inhibition was removed, and FAD was fully recovered. Nox-Y338F/H364V/W423H potentially transforms nicotine considerably faster than Nox-WT without loss of enzyme thermostability. Overall, using a rational design, we successfully engineered an effective mutant of Nox that would be useful for future applications.

High cotinine levels as an associated factor with frailty status in older adults: evidence from the NHANES study

INTRODUCTION

Smoking has been recognized as a contributing factor to frailty in older adults. Nevertheless, it remains uncertain whether the degree of smoking has a discernible impact on frailty among older smokers. This cross-sectional study was conducted to investigate the correlation between serum cotinine levels, a biomarker reflecting tobacco exposure, and the presence of frailty within a nationally representative cohort of older adults.

METHOD

A total of 1626 individuals aged ≥ 60 who identified as smokers were included in the analysis. Participants were selected based on self-reported current smoking status. According to the Fried Phenotype, frailty is assessed through five dimensions: unintentional weight loss, slow walking speed, weakness, self-reported exhaustion, and low physical activity. Participants with three or more of these conditions were categorized as frailty, those with at least one but less than three as pre-frailty, and those with none as robust. Multinomial logistic regression models were employed to explore the relationship between serum cotinine level quartiles, with the lowest quartile as the reference group, and the various frailty statuses, with robustness as the reference category. These models were adjusted for covariates, including age, sex, race/ethnicity, alcohol drinking, daily protein intake, systolic blood pressure, serum albumin level, depressive symptoms, and cognitive function. The data used for this analysis were sourced from the National Health and Nutrition Examination Survey for the years 2011 to 2014.

RESULTS

The median age of the participants was 69.0 years. The majority were male (62.2%) and non-Hispanic White (49.0%). The distribution of frailty statuses among the participants revealed that the highest proportion had pre-frailty (50.7%), followed by robustness (41.1%), and frailty (8.2%). Multinomial logistic regression showed that participants in the 4th quartile of serum cotinine level exhibited a higher probability of pre-frailty versus robustness (Odds ratio [OR] 1.599, 95% confidence interval [CI] 1.017, 2.513, P = 0.042). Participants in the 3rd quartile of serum cotinine level had higher odds of frailty versus robustness (OR 2.403, 95% CI 1.125, 5.134, P = 0.024). Moreover, participants whose serum cotinine levels were higher than the literature cutoffs (≥ 15 ng/ml) were more likely to be pre-frail (Odds ratio [OR] 1.478, 95% confidence interval [CI] 1.017, 2.150, P = 0.035) or frail (Odds ratio [OR] 2.141, 95% confidence interval [CI] 1.054, 4.351, P = 0.041).

CONCLUSIONS

A higher serum cotinine level is linked to an elevated probability of pre-frailty and frailty among older smokers. Initiatives geared towards assisting older smokers in reducing or quitting their smoking habits might possibly play a crucial role in preventing pre-frailty and frailty.

Effects of 3D ultrasonography and 3D printed images on maternal-fetal attachment and its correlation with overall smoking within pregnancy: a pilot study

BACKGROUND

Smoking in pregnancy continues to cause significant morbidity to mothers and babies and contributes to tremendous costs to society. Maternal-fetal attachment (MFA) may differentiate smokers who quit or pregnant smokers from non-smokers. Researchers have recommended utilizing interventions that improve MFA to help decrease smoking within pregnancy.

METHODS

We performed a randomized clinical trial of pregnant smokers (n = 33) using an MFA-informed, intention-to-treat protocol. We recruited pregnant smokers and provided timeline follow back (TLFB) interviews from 27 weeks of pregnancy until 6 weeks post-partum. Salivary cotinine was also collected at five different time points. 3D ultrasonography was performed, and patients were randomly assigned a 3D picture or a 3D model of their fetus.

RESULTS

Overall, the average percent reduction in cigarette use was 37.03% (SD = 31.18). The main effect of 3D type was not significant (3D Model vs. 3D Print Estimate = -0.09, 95% CI: - 0.19 to 0.01, p = 0.066). A total of 4 patients (12%) quit smoking within one week of delivery. A 10% reduction in cigarette use was associated with a 30.57 g increase in birth weight (Estimate = 30.57, 95% CI: -14.15 to 75.29); a 10% reduction in cigarette use was associated with a 0.14 week increase in estimate gestational age at delivery (Estimate = 0.14, 95% CI: -0.01 to 0.28).

CONCLUSIONS

Patients who smoke in pregnancy decrease the number of cigarettes smoked after receiving either a 3D picture or 3D model of their fetus.

TRIAL REGISTRATION

clinicaltrials.gov (NCT04541121).

Qualitative interviews for hospitalists addressing lung cancer screening

Novel strategies are needed to improve low rates of lung cancer screening (LCS) in the US. Seeking to determine hospitalists' perspectives on leveraging hospitalizations to identify patients eligible for LCS, we performed qualitative interviews with eight hospitalists from two hospitals within a large integrated healthcare system. The interviews used semi-structured questions to assess (1) knowledge and practice of general screening and LCS guidelines from the United States Preventive Services Task Force (USPSTF), (2) identification of smoking history, and (3) hospitalists' views on how data obtained during hospitalization may be utilized to improve general screening and LCS post hospitalization. We ultimately reached the conclusion that hospitalists would support a dedicated program to identify hospitalized patients eligible for LCS and facilitate testing after discharge. Efforts to identify patients and arrange subsequent screening should be performed by team members outside the inpatient team.

The effect of healthy eating on the development of stomach and colorectal cancer by the smoking and drinking status: Results from the Korean National Cancer Center (KNCC) community cohort study

BACKGROUND

Determining the effect of dietary factors on cancer is a crucial issue when accounting for the effect of other major risks, such as smoking and drinking.

METHOD

A total of 15,563 adults from the Korean National Cancer Center Community Cohort were analyzed to determine and to compare the effect of dietary factors on stomach and colorectal cancer in overall and in the subgroup of non-smokers (or urinary cotinine concentrations <5 ng/mg) and non-drinkers with Cox proportional-hazard models.

RESULTS

During the mean follow-up (13.7 years), 469 and 299 cases of stomach and colorectal cancer were identified, respectively. The preventive effect of vegetable, fish, and soybean/tofu intake on colorectal cancer was found in women after adjustment for smoking, drinking, BMI, and sociodemographic factors. In the subgroup analysis of non-smokers and non-drinkers, the effect on colorectal cancer was increased in women (≥1 time/week vs. almost never, vegetables: hazard ratio (HR) 0.30, 95% confidence interval (CI) 0.13-0.69; fish: HR 0.46, 95% CI 0.26-0.83), and the fresh fish intake effect on stomach cancer was newly identified in men (HR 0.36, 95% CI 0.15-0.86). These effects were more pronounced and additionally shown in other dietary factors such as soybean or tofu in women and vegetables and fish in men, when subjects with <5 ng/mg urinary cotinine concentrations applied.

CONCLUSION

The protective effect of healthy eating on the risk of stomach and colorectal cancer were different by smoking and drinking status. Rigorous control of smoking and drinking effects is necessary when measuring the effect of dietary factors on cancer, properly.

Blood cell parameters and risk of nonalcoholic fatty liver disease: a comprehensive Mendelian randomization study

BACKGROUND

Nonalcoholic fatty liver disease (NAFLD) is on the rise globally, and past research suggests a significant association with various blood cell components. Our goal is to explore the potential correlation between whole blood cell indices and NAFLD risk using Mendelian randomization (MR).

METHODS

We analyzed data from 4,198 participants in the 2017-2018 National Health and Nutrition Examination Survey to investigate the link between blood cell indicators and NAFLD. Using various methods like weighted quantile sum and multivariate logistic regression, we assessed the association. Additionally, two-sample Mendelian randomization were employed to infer causality for 36 blood cell indicators and NAFLD.

RESULTS

Multivariate logistic regression identified 10 NAFLD risk factors. Weighted quantile sum revealed a positive correlation (p = 6.03e-07) between total blood cell indices and NAFLD, with hemoglobin and lymphocyte counts as key contributors. Restricted cubic spline analysis found five indicators with significant nonlinear correlations to NAFLD. Mendelian randomization showed a notable association between reticulocyte counts and NAFLD using the inverse-variance weighted method.

CONCLUSIONS

Hematological markers pose an independent NAFLD risk, with a positive causal link found for reticulocyte count. These results emphasize the importance of monitoring NAFLD and investigating specific underlying mechanisms further.

Combined and sequential exposure to prenatal second hand smoke and postnatal maternal distress is associated with cingulo-opercular global efficiency and attention problems in school-age children

BACKGROUND

Prenatal exposure to secondhand (environmental) tobacco smoke (SHS) is associated with adverse neurodevelopmental outcomes, including altered functional activation of cognitive control brain circuitry and increased attention problems in children. Exposure to SHS is more common among Black youth who are also disproportionately exposed to socioeconomic disadvantage and concomitant maternal distress. We examine the combined effects of exposure to prenatal SHS and postnatal maternal distress on the global efficiency (GE) of the brain's cingulo-opercular (CO) and fronto-parietal control (FP) networks in childhood, as well as associated attention problems.

METHODS

Thirty-two children of non-smoking mothers followed in a prospective longitudinal birth cohort at the Columbia Center for Children's Environmental Health (CCCEH) completed magnetic resonance imaging (MRI) at ages 7-9 years old. GE scores were extracted from general connectivity data collected while children completed the Simon Spatial Incompatibility functional magnetic resonance imaging (fMRI) task. Prenatal SHS was measured using maternal urinary cotinine from the third trimester; postnatal maternal distress was assessed at child age 5 using the Psychiatric Epidemiology Research Interview (PERI-D). The Child Behavior Checklist (CBCL) measured Attention and Attention Deficit Hyperactivity Disorder (ADHD) problems at ages 7-9. Linear regressions examined the interaction between prenatal SHS and postnatal maternal distress on the GE of the CO or FP networks, as well as associations between exposure-related network alterations and attention problems. All models controlled for age, sex, maternal education at prenatal visit, race/ethnicity, global brain correlation, and mean head motion.

RESULTS

The prenatal SHS by postnatal maternal distress interaction term associated with the GE of the CO network (β = 0.673, Bu = 0.042, t(22) = 2.427, p = .024, D = 1.42, 95% CI [0.006, 0.079], but not the FP network (β = 0.138, Bu = 0.006, t(22) = 0.434, p = .668, 95% CI [-0.022, 0.033]). Higher GE of the CO network was associated with more attention problems (β = 0.472, Bu = 43.076, t(23) = 2.780, p = .011, D = 1.74, n = 31, 95% CI [11.024, 75.128], n = 31) and ADHD risk (β = 0.436, Bu = 21.961, t(29) = 2.567, p = .018, D = 1.81, 95% CI [4.219, 39.703], n = 30).

CONCLUSIONS

These preliminary findings suggest that sequential prenatal SHS exposure and postnatal maternal distress could alter the efficiency of the CO network and increase risk for downstream attention problems and ADHD. These findings are consistent with prior studies showing that prenatal SHS exposure is associated with altered function of brain regions that support cognitive control and with ADHD problems. Our model also identifies postnatal maternal distress as a significant moderator of this association. These data highlight the combined neurotoxic effects of exposure to prenatal SHS and postnatal maternal distress. Critically, such exposures are disproportionately distributed among youth from minoritized groups, pointing to potential pathways to known mental health disparities.

A comparison of feature selection methodologies and learning algorithms in the development of a DNA methylation-based telomere length estimator

BACKGROUND

The field of epigenomics holds great promise in understanding and treating disease with advances in machine learning (ML) and artificial intelligence being vitally important in this pursuit. Increasingly, research now utilises DNA methylation measures at cytosine-guanine dinucleotides (CpG) to detect disease and estimate biological traits such as aging. Given the challenge of high dimensionality of DNA methylation data, feature-selection techniques are commonly employed to reduce dimensionality and identify the most important subset of features. In this study, our aim was to test and compare a range of feature-selection methods and ML algorithms in the development of a novel DNA methylation-based telomere length (TL) estimator. We utilised both nested cross-validation and two independent test sets for the comparisons.

RESULTS

We found that principal component analysis in advance of elastic net regression led to the overall best performing estimator when evaluated using a nested cross-validation analysis and two independent test cohorts. This approach achieved a correlation between estimated and actual TL of 0.295 (83.4% CI [0.201, 0.384]) on the EXTEND test data set. Contrastingly, the baseline model of elastic net regression with no prior feature reduction stage performed less well in general-suggesting a prior feature-selection stage may have important utility. A previously developed TL estimator, DNAmTL, achieved a correlation of 0.216 (83.4% CI [0.118, 0.310]) on the EXTEND data. Additionally, we observed that different DNA methylation-based TL estimators, which have few common CpGs, are associated with many of the same biological entities.

CONCLUSIONS

The variance in performance across tested approaches shows that estimators are sensitive to data set heterogeneity and the development of an optimal DNA methylation-based estimator should benefit from the robust methodological approach used in this study. Moreover, our methodology which utilises a range of feature-selection approaches and ML algorithms could be applied to other biological markers and disease phenotypes, to examine their relationship with DNA methylation and predictive value.

Molecular mechanisms of environmental exposures and human disease

A substantial proportion of disease risk for common complex disorders is attributable to environmental exposures and pollutants. An appreciation of how environmental pollutants act on our cells to produce deleterious health effects has led to advances in our understanding of the molecular mechanisms underlying the pathogenesis of chronic diseases, including cancer and cardiovascular, neurodegenerative and respiratory diseases. Here, we discuss emerging research on the interplay of environmental pollutants with the human genome and epigenome. We review evidence showing the environmental impact on gene expression through epigenetic modifications, including DNA methylation, histone modification and non-coding RNAs. We also highlight recent studies that evaluate recently discovered molecular processes through which the environment can exert its effects, including extracellular vesicles, the epitranscriptome and the mitochondrial genome. Finally, we discuss current challenges when studying the exposome - the cumulative measure of environmental influences over the lifespan - and its integration into future environmental health research.

Association between cigarette smoking and ovarian reserve among women seeking fertility care

INTRODUCTION

This study examined the association of smoking with ovarian reserve in a cross-sectional study of 207 women enrolled in the Louisville Tobacco Smoke Exposure, Genetic Susceptibility, and Infertility (LOUSSI) Study and assessed effect modification by NAT2 acetylator phenotype.

METHODS

Information on current smoking status was collected using a structured questionnaire and confirmed by cotinine assay. Serum anti-Müllerian hormone (AMH) levels were used to assess ovarian reserve. Diminished ovarian reserve (DOR) was defined as AMH <1ng/mL. Single nucleotide polymorphisms in the NAT2 gene, which metabolizes toxins found in cigarette smoke, were analyzed to determine NAT2 acetylator status. Linear and logistic regression were used to determine the effects of smoking on ovarian reserve and evaluate effect modification by NAT2. Regression analyses were stratified by polycystic ovary syndrome (PCOS) status and adjusted for age.

RESULTS

Current smoking status, either passive or active as measured by urinary cotinine assay, was not significantly associated with DOR. For dose-response assessed using self-report, the odds of DOR increased significantly for every additional cigarette currently smoked (Odds ratio, OR:1.08; 95% confidence interval, 95%CI:1.01-1.15); additionally, every 1 pack-year increase in lifetime exposure was associated with an increased odds of DOR among women without PCOS (OR: 1.08 95%CI: 0.99-1.18). These trends appear to be driven by the heavy or long-term smokers. Effect modification by NAT2 genotype was not established.

CONCLUSION

A history of heavy smoking may indicate increased risk of diminished ovarian reserve.

The potential of DNA methylation as a biomarker for obesity and smoking

DNA methylation is an epigenetic modification that has consistently been shown to be linked with a variety of human traits and diseases. Because DNA methylation is dynamic and potentially reversible in nature and can reflect environmental exposures and predict the onset of diseases, it has piqued interest as a potential disease biomarker. DNA methylation patterns are more stable than transcriptomic or proteomic patterns, and they are relatively easy to measure to track exposure to different environments and risk factors. Importantly, technologies for DNA methylation quantification have become increasingly cost effective-accelerating new research in the field-and have enabled the development of novel DNA methylation biomarkers. Quite a few DNA methylation-based predictors for a number of traits and diseases already exist. Such predictors show potential for being more accurate than self-reported or measured phenotypes (such as smoking behavior and body mass index) and may even hold potential for applications in clinics. In this review, we will first discuss the advantages and challenges of DNA methylation biomarkers in general. We will then review the current state and future potential of DNA methylation biomarkers in two human traits that show rather consistent alterations in methylome-obesity and smoking. Lastly, we will briefly speculate about the future prospects of DNA methylation biomarkers, and possible ways to achieve them.

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

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

Assessment and Counseling Gaps Among Former Smokers Eligible for Lung Cancer Screening in US Adults : A Cross-Sectional Analysis of National Health and Nutrition Examination Surveys (NHANES), 2013-2018

BACKGROUND

Lung cancer screening (LCS) for former and current smokers requires that current smokers are counseled on tobacco treatment. In the USA, over 4 million former smokers are estimated to be eligible for LCS based on self-report for "not smoking now." Tobacco use and exposure can be measured with the biomarker cotinine, a nicotine metabolite reflecting recent exposure.

OBJECTIVE

To examine predictors of tobacco use and exposure among self-reported former smokers eligible for LCS.

DESIGN

Cross-sectional study using the 2013-2018 National Health and Nutrition Examination Survey.

PARTICIPANTS

Former smokers eligible for LCS (n = 472).

MAIN MEASURES

Recent tobacco use was defined as reported tobacco use in the past 5 days or a cotinine level above the race/ethnic cut points for tobacco use. Recent tobacco exposure was measured among former smokers without recent tobacco use and defined as having a cotinine level above 0.05 ng/mL.

KEY RESULTS

One in five former smokers eligible for LCS, totaling 1,416,485 adults, had recent tobacco use (21.4%, 95% confidence interval (CI) 15.8%, 27.0%), with about a third each using cigarettes, e-cigarettes, or other tobacco products. Among former smokers without recent tobacco use, over half (53.0%, 95% CI: 44.6%, 61.4%) had cotinine levels indicating recent tobacco exposure. Certain subgroups had higher percentages for tobacco use or exposure, especially those having quit within the past 3 years or living with a household smoker.

CONCLUSIONS

Former smokers eligible for LCS should be asked about recent tobacco use and exposure and considered for cotinine testing. Nearly 1.5 million "former smokers" eligible for LCS may be current tobacco users who have been missed for counseling. The high percentage of "passive smokers" is at least double that of the general nonsmoking population. Counseling about the harms of tobacco use and exposure and resources is needed.

Prenatal environmental tobacco smoke exposure alters children's cognitive control circuitry: A preliminary study

BACKGROUND AND OBJECTIVES

Prenatal exposure to environmental tobacco smoke (ETS) is associated with increased attention problems in children, however, the effects of such exposure on children's brain structure and function have not been studied. Herein, we probed effects of prenatal ETS on children's cognitive control circuitry and behavior.

METHODS

Forty-one children (7-9 years) recruited from a prospective longitudinal birth cohort of non-smoking mothers completed structural and task-functional magnetic resonance imaging to evaluate effects of maternal ETS exposure, measured by maternal prenatal urinary cotinine. Attention problems and externalizing behaviors were measured by parent report on the Child Behavior Checklist.

RESULTS

Compared to non-exposed children, exposed children had smaller left and right thalamic and inferior frontal gyrus (IFG) volumes, with large effect sizes (p-FDR < .05, Cohen's D range from 0.79 to 1.07), and increased activation in IFG during the resolution of cognitive conflict measured with the Simon Spatial Incompatibility Task (38 voxels; peak t(25) = 5.25, p-FWE = .005). Reduced thalamic volume was associated with increased IFG activation and attention problems, reflecting poor cognitive control. Mediation analyses showed a trend toward left thalamic volume mediating the association between exposure and attention problems (p = .05).

CONCLUSIONS

Our findings suggest that maternal ETS exposure during pregnancy has deleterious effects on the structure and function of cognitive control circuitry which in turn affects attentional capacity in school-age children. These findings are consistent with prior findings documenting the effects of active maternal smoking on chidlren's neurodevleoment, pointing to the neurotixicity of nicotine regardless of exposure pathway.

Association of smoking status with hospitalisation for COVID-19 compared with other respiratory viruses a year previous: a case-control study at a single UK National Health Service trust

Background: It is unclear whether smoking increases the risk of COVID-19 hospitalisation. We first examined the association of smoking status with hospitalisation for COVID-19 compared with hospitalisation for other respiratory viral infections a year previous. Second, we examined the concordance between smoking status recorded on the electronic health record (EHR) and the contemporaneous medical notes. Methods: This case-control study enrolled adult patients (446 cases and 211 controls) at a single National Health Service trust in London, UK. The outcome variable was type of hospitalisation (COVID-19 vs. another respiratory virus a year previous). The exposure variable was smoking status (never/former/current smoker). Logistic regression analyses adjusted for age, sex, socioeconomic position and comorbidities were performed. The study protocol and analyses were pre-registered in April 2020 on the Open Science Framework. Results: Current smokers had lower odds of being hospitalised with COVID-19 compared with other respiratory viruses a year previous (OR adj=0.55, 95% CI=0.31-0.96,  p=.04). There was no significant association among former smokers (OR adj=1.08, 95% CI=0.72-1.65,  p=.70). Smoking status recorded on the EHR (compared with the contemporaneous medical notes) was incorrectly recorded for 168 (79.6%) controls (χ 2(3)=256.5,  p=<0.001) and 60 cases (13.5%) (χ 2(3)=34.2,  p=<0.001). Conclusions: In a single UK hospital trust, current smokers had reduced odds of being hospitalised with COVID-19 compared with other respiratory viruses a year previous, although it is unclear whether this association is causal. Targeted post-discharge recording of smoking status may account for the greater EHR-medical notes concordance observed in cases compared with controls.

Association of smoking status with hospitalisation for COVID-19 compared with other respiratory viruses a year previous: a case-control study at a single UK National Health Service trust

Background: It is unclear whether smoking increases the risk of COVID-19 hospitalisation. We first examined the association of smoking status with hospitalisation for COVID-19 compared with hospitalisation for other respiratory viral infections a year previous. Second, we examined the concordance between smoking status recorded on the electronic health record (EHR) and the contemporaneous medical notes. Methods: This case-control study enrolled adult patients (446 cases and 211 controls) at a single National Health Service trust in London, UK. The outcome variable was type of hospitalisation (COVID-19 vs. another respiratory virus a year previous). The exposure variable was smoking status (never/former/current smoker). Logistic regression analyses adjusted for age, sex, socioeconomic position and comorbidities were performed. The study protocol and analyses were pre-registered in April 2020 on the Open Science Framework. Results: Current smokers had lower odds of being hospitalised with COVID-19 compared with other respiratory viruses a year previous (OR adj=0.55, 95% CI=0.31-0.96,  p=.04). There was no significant association among former smokers (OR adj=1.08, 95% CI=0.72-1.65,  p=.70). Smoking status recorded on the EHR (compared with the contemporaneous medical notes) was incorrectly recorded for 168 (79.6%) controls (χ 2(3)=256.5,  p=<0.001) and 60 cases (13.5%) (χ 2(3)=34.2,  p=<0.001). Conclusions: In a single UK hospital trust, current smokers had reduced odds of being hospitalised with COVID-19 compared with other respiratory viruses a year previous, although it is unclear whether this association is causal. Targeted post-discharge recording of smoking status may account for the greater EHR-medical notes concordance observed in cases compared with controls.

Association of smoking status with hospitalisation for COVID-19 compared with other respiratory viruses a year previous: a case-control study at a single UK National Health Service trust

Background: It is unclear whether smoking increases the risk of COVID-19 hospitalisation. We first examined the association of smoking status with hospitalisation for COVID-19 compared with hospitalisation for other respiratory viral infections a year previous. Second, we examined the concordance between smoking status recorded on the electronic health record (EHR) and the contemporaneous medical notes. Methods: This case-control study enrolled adult patients (446 cases and 211 controls) at a single National Health Service trust in London, UK. The outcome variable was type of hospitalisation (COVID-19 vs. another respiratory virus a year previous). The exposure variable was smoking status (never/former/current smoker). Logistic regression analyses adjusted for age, sex, socioeconomic position and comorbidities were performed. The study protocol and analyses were pre-registered in April 2020 on the Open Science Framework. Results: Current smokers had lower odds of being hospitalised with COVID-19 compared with other respiratory viruses a year previous (OR adj=0.55, 95% CI=0.31-0.96,  p=.04). There was no significant association among former smokers (OR adj=1.08, 95% CI=0.72-1.65,  p=.70). Smoking status recorded on the EHR (compared with the contemporaneous medical notes) was incorrectly recorded for 168 (79.6%) controls (χ 2(3)=256.5,  p=<0.001) and 60 cases (13.5%) (χ 2(3)=34.2,  p=<0.001). Conclusions: In a single UK hospital trust, current smokers had reduced odds of being hospitalised with COVID-19 compared with other respiratory viruses a year previous, although it is unclear whether this association is causal. Targeted post-discharge recording of smoking status may account for the greater EHR-medical notes concordance observed in cases compared with controls.

The association of smoking status with SARS-CoV-2 infection, hospitalization and mortality from COVID-19: a living rapid evidence review with Bayesian meta-analyses (version 7)

AIMS

To estimate the association of smoking status with rates of (i) infection, (ii) hospitalization, (iii) disease severity and (iv) mortality from SARS-CoV-2/COVID-19 disease.

DESIGN

Living rapid review of observational and experimental studies with random-effects hierarchical Bayesian meta-analyses. Published articles and pre-prints were identified via MEDLINE and medRxiv.

SETTING

Community or hospital, no restrictions on location.

PARTICIPANTS

Adults who received a SARS-CoV-2 test or a COVID-19 diagnosis.

MEASUREMENTS

Outcomes were SARS-CoV-2 infection, hospitalization, disease severity and mortality stratified by smoking status. Study quality was assessed (i.e. 'good', 'fair' and 'poor').

FINDINGS

Version 7 (searches up to 25 August 2020) included 233 studies with 32 'good' and 'fair' quality studies included in meta-analyses. Fifty-seven studies (24.5%) reported current, former and never smoking status. Recorded smoking prevalence among people with COVID-19 was generally lower than national prevalence. Current compared with never smokers were at reduced risk of SARS-CoV-2 infection [relative risk (RR) = 0.74, 95% credible interval (CrI) = 0.58-0.93, τ = 0.41]. Data for former smokers were inconclusive (RR = 1.05, 95% CrI = 0.95-1.17, τ = 0.17), but favoured there being no important association (21% probability of RR ≥ 1.1). Former compared with never smokers were at somewhat increased risk of hospitalization (RR = 1.20, CrI = 1.03-1.44, τ = 0.17), greater disease severity (RR = 1.52, CrI = 1.13-2.07, τ = 0.29) and mortality (RR = 1.39, 95% CrI = 1.09-1.87, τ = 0.27). Data for current smokers were inconclusive (RR = 1.06, CrI = 0.82-1.35, τ = 0.27; RR = 1.25, CrI = 0.85-1.93, τ = 0.34; RR = 1.22, 95% CrI = 0.78-1.94, τ = 0.49, respectively), but favoured there being no important associations with hospitalization and mortality (35% and 70% probability of RR ≥ 1.1, respectively) and a small but important association with disease severity (79% probability of RR ≥ 1.1).

CONCLUSIONS

Compared with never smokers, current smokers appear to be at reduced risk of SARS-CoV-2 infection, while former smokers appear to be at increased risk of hospitalization, increased disease severity and mortality from COVID-19. However, it is uncertain whether these associations are causal.

Self-Reported Smoking Compared to Serum Cotinine in Bariatric Surgery Patients: Smoking Is Underreported Before the Operation

BACKGROUND

Smoking has been associated with postoperative complications and mortality in bariatric surgery. The evidence for smoking is based on self-report and medical charts, which can lead to misclassification and miscalculation of the associations. Determination of cotinine can objectively define nicotine exposure. We determined the accuracy of self-reported smoking compared to cotinine measurement in three phases of the bariatric surgery trajectory.

METHODS

Patients in the phase of screening (screening), on the day of surgery (surgery), and more than 18 months after surgery (follow-up) were consecutively selected. Self-reported smoking was registered and serum cotinine was measured. We evaluated the accuracy of self-reported smoking compared to cotinine, and the level of agreement between self-report and cotinine for each phase.

RESULTS

In total, 715 patients were included. In the screening, surgery, and follow-up group, 25.6%, 18.0%, and 15.5%, respectively, was smoking based on cotinine. The sensitivity of self-reported smoking was 72.5%, 31.0%, and 93.5% in the screening, surgery, and follow-up group, respectively (p < 0.001). The specificity of self-report was > 95% in all groups (p < 0.02). The level of agreement between self-report and cotinine was 0.778, 0.414, and 0.855 for the screening, surgery, and follow-up group, respectively.

CONCLUSIONS

Underreporting of smoking occurs before bariatric surgery, mainly on the day of surgery. Future studies on effects of smoking and smoking cessation in bariatric surgery should include methods taking into account the issue of underreporting.

EpiSmokEr: a robust classifier to determine smoking status from DNA methylation data

Aim: Smoking strongly influences DNA methylation, with current and never smokers exhibiting different methylation profiles. Methods: To advance the practical applicability of the smoking-associated methylation signals, we used machine learning methodology to train a classifier for smoking status prediction. Results: We show the prediction performance of our classifier on three independent whole-blood datasets demonstrating its robustness and global applicability. Furthermore, we examine the reasons for biologically meaningful misclassifications through comprehensive phenotypic evaluation. Conclusion: The major contribution of our classifier is its global applicability without a need for users to determine a threshold value for each dataset to predict the smoking status. We provide an R package, EpiSmokEr (Epigenetic Smoking status Estimator), facilitating the use of our classifier to predict smoking status in future studies.

Critical steps in the path to using cessation pharmacotherapy following hospital-initiated tobacco treatment

Background

Hospital-initiated smoking cessation interventions utilizing pharmacotherapy increase post-discharge quit rates. Use of smoking cessation medications following discharge may further increase quit rates. This study aims to identify individual, smoking-related and hospitalization-related predictors of engagement in three different steps in the smoking cessation pharmacotherapy utilization process: 1) receiving medications as inpatient, 2) being discharged with a prescription and 3) using medications at 1-month post-hospitalization, while accounting for associations between these steps.

Methods

Study data come from a clinical trial (N = 1054) of hospitalized smokers interested in quitting who were randomized to recieve referral to a quitline via either warm handoff or fax. Variables were from the electronic health record, the state tobacco quitline, and participant self-report. Relationships among the predictors and the steps in cessation medication utilization were assessed using bivariate analyses and multivariable path analysis.

Results

Twenty-eight percent of patients reported using medication at 1-month post-discharge. Receipt of smoking cessation medications while hospitalized (OR = 2.09, 95%CI [1.39, 3.15], p < .001) and discharge with a script (OR = 4.88, 95%CI [3.34, 7.13], p < .001) were independently associated with medication use at 1-month post-hospitalization. The path analysis also revealed that the likelihood of being discharged with a script was strongly influenced by receipt of medication as an inpatient (OR = 6.61, 95%CI [4.66, 9.38], p < .001). A number of other treatment- and individual-level factors were associated with medication use in the hospital, receipt of a script, and use post-discharge.

Conclusions

To encourage post-discharge smoking cessation medication use, concerted effort should be made to engage smokers in tobacco treatment while in hospital. The individual and hospital-level factors associated with each step in the medication utilization process provide good potential targets for future implementation research to optimize treatment delivery and outcomes.

Trial registration

Number: NCT01305928.

Date registered: February 24, 2011.

The Determinants of Salivary Cotinine Concentration in Smokeless Tobacco Users

BACKGROUND

Smokeless tobacco products due to their high nicotine content are highly addictive and ultimately lead to an increased risk of oral cavity, laryngeal and oesophagal cancer.

AIM

This research was conducted with the aim of assessing the relationship between the salivary cotinine concentration and demographic characteristics and smokeless tobacco use for the first time in tradespeople in Chabahar, Iran.

METHODS

This descriptive cross-sectional study was conducted on 150 different tradespeople using smokeless tobacco in Chabahar who were selected through simple random sampling in 2018. In addition to the salivary cotinine measurement, data were collected using a researcher-made questionnaire with demographic and behavioural items. The data obtained were analysed in SPSS-16 using descriptive and inferential statistics.

RESULTS

The mean salivary cotinine score was 887.7 ± 180.7 in men and 611.2 ± 139.7 in women, making for a significant intergroup difference (P = 0.043). The mean salivary cotinine score was higher in those who used two or more smokeless tobacco products compared to those who used one type of tobacco, and a significant difference was observed between the type of smokeless tobacco used and the salivary cotinine score in the participants (P = 0.005).

CONCLUSION

Based on the results of the regression analysis, the type of smokeless tobacco used was a strong predictor of the concentration of salivary cotinine in the participants. It is, therefore, necessary for the government to adopt appropriate policies and take educational measures to reduce the vending and use of these substances.

Effects of nicotine on rat adrenal gland: crosstalk between oxidative and inflammatory markers, and amelioration by melatonin

Although the risks of smoking are well known, the effects of exposure to nicotine on endocrine functions remain unclear. We investigated the deleterious effects of nicotine on the adrenal gland and the mechanisms of these changes in rats. The role of melatonin in ameliorating pathological changes also was investigated. We used 24 rats divided into four groups of six: group 1, control; group 2, nicotine treated; group 3, nicotine and melatonin treated; group 4, melatonin treated. We used histology; immunohistochemistry of inducible nitric oxide synthase (iNOS), vascular endothelial growth factor (VEGF) and tyrosine hydroxylase (TH); measured oxidative and antioxidative markers, malondialdehyde (MDA) and glutathione (GSH); and performed real-time PCR for NF-κB 65, IL1-B and IL6. We also performed histomorphometric analysis. Indentation and lamellar separation of the adrenal capsule, vacuolated degenerated cells and lymphocytic infiltration were observed in group 2. Vacuolated cells and cells with pyknotic nuclei also were detected in the zona reticularis and medulla of the same group. We observed improved shape and cellular lining of the gland in groups 3 and 4. Widespread expression of iNOS, VEGF and TH, increased area percent collagen, decreased GSH (56%) and increased MDA, NF-κB, IL1-B and IL-6 were observed in group 2. All parameters were ameliorated in groups 3 and 4. The effects of nicotine on the adrenal gland can be attributed to oxidative and inflammatory stress; melatonin ameliorates these effects.

A retrospective analysis of the association between providing nicotine replacement therapy at admission and motivation to quit and nicotine withdrawal symptoms during an inpatient psychiatric hospitalization

BACKGROUND

Psychiatric patients have high tobacco use prevalence, dependence, and withdrawal severity. A tobacco-free psychiatric hospitalization necessitates the management of nicotine withdrawal (NW) for tobacco using patients. NW management often requires the provision of approved nicotine replacement therapy (NRT) to patients, which may also motivate tobacco users towards cessation. However, few studies have examined the associations between providing NRT, motivation to quit, and NW among psychiatric patients.

OBJECTIVE(S)

To examine the associations between providing NRT at admission and motivation to quit smoking and severity of NW symptoms.

DESIGN

A retrospective review of the medical records of 255 tobacco using patients on whom NW was assessed during their hospital stay. The time when NRT was provided (i.e., at admission vs. not provided vs. on the unit), motivation to quit smoking, and 8-item Minnesota Nicotine Withdrawal Scale were assessed.

RESULTS

The primary NW symptom was 'craving' (65.1%); reporting of 'anxiety' varied by psychiatric diagnosis. Providing NRT at admission was not associated with motivation to quit. Patients receiving NRT on the unit (i.e., delayed receipt) had significantly higher NW than those who received NRT at admission. In multivariate analyses, receiving NRT on the unit was significantly associated with greater NW severity (β = .19, p = .002).

CONCLUSIONS

Among psychiatric patients, providing NRT at admission is associated with greater severity of NW. The provision of NRT for NW management may be considered as standard practice during tobacco-free psychiatric stays. Future studies may consider the effect of other tobacco treatment medications (such as varenicline, bupropion) on managing NW.

Cigarette smoking and glaucoma in the United States population

PurposeTo evaluate the association between cigarette smoking and glaucoma in the United States population.Patients and methodsUS civilian, non-institutionalized population from 2005 to 2008 administrations of the National Health and Nutrition Examination Survey that were ≥40 years of age with visual fields and optic disc photographs were included. Diagnosis of glaucoma was based on the Rotterdam criteria. Logistic regression modeling was performed to assess the association between glaucoma and smoking history, while controlling for age, gender, ethnicity, household income, alcohol consumption, diabetes, and hypertension.ResultsIn 3864 participants, 212 (5.5%) had glaucoma (corresponds to a population weighted glaucoma prevalence of 3.7% in a total of 83 570 127 subjects). Population weighted proportion of current smokers was 20.6% and ex-smokers was 28.3%. Participants with glaucoma were older (63.0±11.6 vs 56.1±11.2, P=0.002), likely to be male (57.1% vs 49.2%, P=0.03), to be Black (36.3% vs 20.7%, P<0.001), and to have diabetes (18.9% vs 12.4%, P=0.006) and hypertension (50.5% vs 39.7%, P=0.003). Current smokers had a lower odds of glaucoma compared to non-smokers (OR=0.61, 95% CI=0.41-0.88, P=0.009), and ex-smokers (OR=0.46, 95% CI=0.28-0.76, P=0.002). The effect estimates were similar in adjusted models, but not statistically significant. Among smokers, greater pack/day of smoking history was associated with statistically significantly higher odds of glaucoma (OR=1.70, 95% CI=1.08-2.67, P=0.02).ConclusionsAmong cigarette smokers, heavy smoking defined by greater number of pack of cigarettes smoked per day is associated with higher odds of glaucoma. Health care providers should include this association when counseling patients on their smoking habit.

A phase II trial of erlotinib monotherapy in advanced pancreatic cancer as a first- or second-line agent

INTRODUCTION

Pancreatic adenocarcinoma carries a grim prognosis. In 2007, gemcitabine with erlotinib emerged as an appropriate treatment option for patients with advanced inoperable or metastatic disease (APC). In this phase II trial we sought to evaluate the efficacy of erlotinib monotherapy in patients with APC who had disease refractory to or ineligibility for gemcitabine-based therapy.

METHODS

Eligible patients who had received 0 or 1 non-EGFR inhibitor containing gemcitabine-based chemotherapy for APC were recruited prospectively and treated with erlotinib 150 mg orally daily until unacceptable toxicity or disease progression. Primary endpoint was progression-free survival (PFS). Correlations of clinical response with smoking, rash, steady-state concentration of erlotinib and its metabolite (OSI-420) as well as the nicotine metabolite cotinine were performed.

RESULTS

The trial was terminated early for futility. Eighteen of the 34 planned subjects were recruited. Median PFS and OS were 42 and 95 days, respectively. Best response was stable disease (21%). There was a trend for improved PFS and OS in never smokers compared to current and past smokers (128.5, 39, 42 days and 173, 100, 88 days, respectively). Past/current smokers had lower steady-state concentrations of erlotinib and OSI-420 compared to never smokers. There was evidence of recent smoking exposure in 30% of patients self-identified as past smokers. Rash was infrequent, with no cases of grade III/IV rash and it was not related to treatment outcomes.

CONCLUSIONS

Overall, erlotinib monotherapy failed to improve outcomes compared to historical controls in patients with APC after 0-1 prior systemic therapies. There was a trend for improved PFS and OS in never smokers.

Provider Perspectives on Adding Biomarker Screening for Tobacco Smoke Exposure to Lead Screening at Well-Child Visits

INTRODUCTION

Measurement of cotinine, a biomarker of tobacco smoke exposure, can accurately identify children at risk of health consequences from secondhand smoke. This study reports perspectives from pediatric health care providers on incorporating routine cotinine screening into well-child visits.

METHODS

Key informant interviews (N = 28) were conducted with pediatric primary care providers: physicians, nurse practitioners, and registered nurses.

RESULTS

Themes identified in the interviews included the following: (a) Cotinine screening would assess children's exposure to tobacco smoke more reliably than parental report; (b) Addressing positive cotinine screening results might require additional resources; (c) Wheezing and a history of emergency department visits increased the salience of cotinine screening; and (d) A better understanding of the significance of specific cotinine test values would improve utility.

DISCUSSION

Pediatric providers see advantages of biomarker screening for tobacco smoke exposure at well-child visits, especially for children with wheezing, but have concerns about limited capacity for follow-up with parents.

Using Behavioral Intervention Technologies to Help Low-Income and Latino Smokers Quit: Protocol of a Randomized Controlled Trial

Background

The Institute for International Internet Interventions for Health at Palo Alto University proposes to develop digital tools specifically to help low-income English- and Spanish-speaking smokers to quit. Individuals from lower-income countries and those with lower social status quit at lower rates than those from high-income countries and those with higher social status.

Objective

We plan to launch a project designed to test whether a mobile-based digital intervention designed with systematic input from low-income English- and Spanish-speaking smokers from a public-sector health care system can significantly improve its acceptability, utilization, and effectiveness.

Methods

Using human-centered development methods, we will involve low-income patients in the design of a Web app/text messaging tool. We will also use their input to improve our recruitment and dissemination strategies. We will iteratively develop versions of the digital interventions informed by our human-centered approach. The project involves three specific aims: (1) human-centered development of an English/Spanish smoking cessation web app, (2) improvement of dissemination strategies, and (3) evaluation of resulting smoking cessation web app. We will develop iterative versions of a digital smoking cessation tool that is highly responsive to the needs and preferences of the users. Input from participants will identify effective ways of reaching and encouraging low-income English- and Spanish-speaking smokers to use the digital smoking cessation interventions to be developed. This information will support ongoing dissemination and implementation efforts beyond the grant period. We will evaluate the effectiveness of the successive versions of the resulting stop smoking Web app by an online randomized controlled trial. Increased effectiveness will be defined as increased utilization of the Web app and higher abstinence rates than those obtained by a baseline usual care Web app.

Results

Recruitment will begin January 2016, the study is intended to be completed by summer 2018, and the results should be available by fall 2019.

Conclusions

This study will provide useful knowledge in developing, testing, and disseminating mobile-based interventions for low-income smokers.

ClinicalTrial

ClinicalTrials.gov NCT02666482; https://clinicaltrials.gov/ct2/show/NCT02666482 (Archived by WebCite at http://www.webcitation.org/6gtcwaT28)

Implementation of a smoke-free policy in an inpatient psychiatric facility: Patient-reported adherence, support, and receipt of nicotine-dependence treatment

The implementation of smoke-free policies in inpatient psychiatric facilities, including patient adherence, mental health nursing staff support, and provision of nicotine-dependence treatment to patients, has been reported to be poor. The extent to which the quality of smoke-free policy implementation is associated with patient views of a policy is unknown. We conducted a cross-sectional survey of 181 patients (53.6%, n = 97 smokers; and 46.4%, n = 84 non-smokers) in an Australian inpatient psychiatric facility with a total smoke-free policy. Smokers' adherence to the policy was poor (83.5% smoked). Only half (53.6%) perceived staff to be supportive of the policy. Most smokers used nicotine-replacement therapy (75.3%); although few received optimal nicotine-dependence treatment (19.6%). Overall, 45.9% of patients viewed the smoke-free policy in the unit as positive (29.9% smokers; 64.3% non-smokers). For smokers, adhering to the ban, perceiving staff to be supportive, and reporting that the nicotine-replacement therapy reduced cravings to smoke were associated with a more positive view towards the smoke-free policy. These findings support the importance of patient adherence, mental health nursing staff support, and adequate provision of nicotine-dependence treatment in strengthening smoke-free policy implementation in inpatient psychiatric settings.

Effects of cigarette smoking and nicotine metabolite ratio on leukocyte telomere length

Studies of the effects of smoking on leukocyte telomere length (LTL) using cigarettes smoked per day or pack years smoked (PYS) present limitations. Reported high levels of smoking may not increase toxin exposure levels proportionally. Nicotine metabolism ratio (NMR) predicts total cigarette puff volume and overall exposure based on total N-nitrosamines, is highly reproducible and independent of time since the last cigarette. We hypothesized that smokers with higher NMRs will exhibit increased total puff volume, reflecting efforts to extract more nicotine from their cigarettes and increasing toxin exposure. In addition, higher levels of smoking could cause a gross damage in LTL. The urinary cotinine, 3-OH cotinine and nicotine levels of 147 smokers were analyzed using a LC/MS system Triple-Q6410. LTL and CYP2A6 genotype was determined by PCR in blood samples. We found a significant association between NMR and CYP2A6 genotype. Reduction in LTL was seen in relation to accumulated tobacco consumption and years smoking when we adjusted for age and gender. However, there were no significant differences between NMR values and LTL. In our study the higher exposure was associated with lower number of PYS. Smokers with reduced cigarette consumption may exhibit compensatory smoking behavior that results in no reduced tobacco toxin exposure. Our results suggest that lifetime accumulated smoking exposure could cause a gross damage in LTL rather than NMR or PYS. Nevertheless, a combination of smoking topography (NMR) and consumption (PYS) measures may provide useful information about smoking effects on health outcomes.

Validity and reliability of the Internalized Stigma of Smoking Inventory: An exploration of shame, isolation, and discrimination in smokers with mental health diagnoses

BACKGROUND AND OBJECTIVES

De-normalization of smoking as a public health strategy may create shame and isolation in vulnerable groups unable to quit. To examine the nature and impact of smoking stigma, we developed the Internalized Stigma of Smoking Inventory (ISSI), tested its validity and reliability, and explored factors that may contribute to smoking stigma.

METHODS

We evaluated the ISSI in a sample of smokers with mental health diagnoses (N = 956), using exploratory and confirmatory factor analysis, and assessed construct validity.

RESULTS

Results reduced the ISSI to eight items with three subscales: smoking self-stigma related to shame, felt stigma related to social isolation, and discrimination experiences. Discrimination was the most commonly endorsed of the three subscales. A multivariate generalized linear model predicted 21-30% of the variance in the smoking stigma subscales. Self-stigma was greatest among those intending to quit; felt stigma was highest among those experiencing stigma in other domains, namely ethnicity and mental illness-based; and smoking-related discrimination was highest among women, Caucasians, and those with more education.

DISCUSSION AND CONCLUSION

Smoking stigma may compound stigma experiences in other areas. Aspects of smoking stigma in the domains of shame, isolation, and discrimination were related to modeled stigma responses, particularly readiness to quit and cigarette addiction, and were found to be more salient for groups where tobacco use is least prevalent.

SCIENTIFIC SIGNIFICANCE

The ISSI measure is useful for quantifying smoking-related stigma in multiple domains.

Smokers with serious mental illness and requests for nicotine replacement therapy post-hospitalisation

BACKGROUND AND AIMS

Smoke-free psychiatric hospitalisation provides opportunity for initiating tobacco cessation treatment. The current study reports on psychiatric patients' interest in continuing nicotine replacement therapy (NRT) posthospitalisation and examines patient predictors of NRT requests, quit attempts and abstinence at 1-week follow-up.

METHODS

Daily smokers were recruited and interviewed on locked psychiatric units at three smoke-free San Francisco Bay Area hospitals. Intent to quit smoking was not required to participate and 73% of eligible smokers enrolled. Analyses focused on 816 participants (49% female) randomised to interventions providing counselling tailored to readiness to quit with availability of NRT posthospitalisation. Logistic regressions tested demographic, smoking and psychiatric factors predictive of NRT requests, quit attempts and abstinence 1-week postdischarge.

RESULTS

Participants averaged 17 (SD=10) cigarettes/day for an average of 19 (SD=14) years. Most (88%) requested study-provided NRT (74% right at discharge). Participants preparing to quit and those with more severe psychiatric symptoms were more likely to request NRT at discharge (p<0.01). Those with more severe psychiatric symptoms also were more likely to request NRT refill, as were older participants (p<0.05). Participants who requested NRT at discharge were more likely to make a 24 h quit attempt and self-report abstinence at the 1-week follow-up (54% quit attempt, 14% abstinent) than participants who did not (25% quit attempt, 4% abstinent) (p<0.05).

CONCLUSIONS

The great demand for NRT and the association between NRT use with quit attempts and abstinence at 1-week posthospitalisation supports adoption of tobacco treatment in acute psychiatric settings.

TRIAL REGISTRATION NUMBER

# NCT00968513.

Prevalence and impact of active and passive cigarette smoking in acute respiratory distress syndrome

OBJECTIVES

Cigarette smoke exposure has recently been found to be associated with increased susceptibility to trauma- and transfusion-associated acute respiratory distress syndrome. We sought to determine 1) the incidence of cigarette smoke exposure in a diverse multicenter sample of acute respiratory distress syndrome patients and 2) whether cigarette smoke exposure is associated with severity of lung injury and mortality in acute respiratory distress syndrome.

DESIGN

Analysis of the Albuterol for the Treatment of Acute Lung Injury and Omega Acute Respiratory Distress Syndrome Network studies.

SETTING

Acute Respiratory Distress Syndrome Network hospitals.

PATIENTS

Three hundred eighty-one patients with acute respiratory distress syndrome.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

4-(Methylnitrosamino)-1-(3-pyridyl)-1-butanol, a validated tobacco-specific marker, was measured in urine samples from subjects enrolled in two National Heart, Lung, and Blood Institute Acute Respiratory Distress Syndrome Network randomized controlled trials. Urine 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanol levels were consistent with active smoking in 36% of acute respiratory distress syndrome patients and with passive smoking in 41% of nonsmokers (vs 20% and 40% in general population, respectively). Patients with 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanol levels in the active smoking range were younger and had a higher incidence of alcohol misuse, fewer comorbidities, lower severity of illness, and less septic shock at enrollment compared with patients with undetectable 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanol levels. Despite this lower severity of illness, the severity of lung injury did not significantly differ based on biomarker-determined smoking status. Cigarette smoke exposure was not significantly associated with death after adjusting for differences in age, alcohol use, comorbidities, and severity of illness.

CONCLUSIONS

In this first multicenter study of biomarker-determined cigarette smoke exposure in acute respiratory distress syndrome patients, we found that active cigarette smoke exposure was significantly more prevalent among acute respiratory distress syndrome patients compared to population averages. Despite their younger age, better overall health, and lower severity of illness, smokers by 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanol had similar severity of lung injury as patients with undetectable 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanol. These findings suggest that active cigarette smoking may increase susceptibility to acute respiratory distress syndrome in younger, healthier patients.

The impact of a smoke-free psychiatric hospitalization on patient smoking outcomes: a systematic review

OBJECTIVE

Smoke-free policies have been introduced in inpatient psychiatric facilities in most developed nations. Such a period of supported abstinence during hospitalization may impact smoking behaviours post discharge, yet little quantitative evidence exists. The aim of this review was to provide the first synthesis of the research evidence examining the impact of a smoke-free psychiatric hospitalization on patients' smoking-related behaviours, motivation, and beliefs.

METHODS

We conducted a systematic review of electronic databases PubMed, MEDLINE, PsycINFO, and EMBASE from inception to June 2013. Studies were included if they were conducted in an inpatient psychiatric facility with a smoke-free policy and if they examined any change in patients' smoking-related behaviours, motivation, or beliefs either during admission, post discharge, or both. Risk of bias was assessed using the Cochrane Collaboration Risk of Bias Tool.

RESULTS

Fourteen studies were included in the review. Of the four studies that assessed change in smoking from admission to post discharge, two indicated a significant decline in cigarette consumption up to 3 months post discharge. Positive changes in motivation to quit and beliefs about quitting ability were identified in two studies. One study reported an increase in the rate of quit attempts and one reported a decline in nicotine dependence levels.

CONCLUSIONS

A smoke-free psychiatric hospitalization may have a positive impact on patients' smoking-related behaviours, motivation, and beliefs, both during admission and up to 3 months post discharge. Further controlled studies with more rigorous designs are required to confirm this potential.

Cigarette smoking as a risk factor for delirium in hospitalized and intensive care unit patients. A systematic review

BACKGROUND

Active smokers are prevalent in hospitalized and critically ill patients. Cigarette smoking and nicotine withdrawal may increase delirium in these populations. This systematic review aims to determine whether active cigarette smoking increases the risk for delirium in hospitalized and intensive care unit (ICU) patients.

METHODS

A systematic search of English-, Spanish-, and French-language articles published from 1966 to April 2013 was performed. Studies were included if they measured cigarette smoking as a risk factor and delirium as an outcome in adult hospitalized or ICU patients. Methodologic quality of studies was assessed using both the validated Newcastle Ottawa Scale and an additional evidence-based quality rating scale.

RESULTS

A total of 14 cohort studies of surgical and ICU populations were included in the review. No studies in non-ICU inpatients were identified. The incidence of delirium ranged from 9 to 52%, and the prevalence of active smokers ranged from 9 to 44%. The quality of assessment for active smoking varied widely. None of the studies used biochemical measures to determine cigarette smoke exposure. Of the six studies restricting the smoking group to active smokers only, active smoking was independently associated with delirium in one study, trended toward an association in one study, and showed a dose response in one study. Quantitative summary measures were not calculated due to study heterogeneity and missing data.

CONCLUSIONS

There is currently insufficient evidence to determine if cigarette smoking is a risk factor for delirium. Future studies should consider using biochemical measures of cigarette smoke exposure to objectively quantify smoking behavior.

Electronic cigarette awareness, use history, and expected future use among hospitalized cigarette smokers

INTRODUCTION

E-cigarette use has surged during the past few years while the debate about the product's safety and efficacy for smoking cessation continues. Little is known about the characteristics that distinguish users from nonusers; in this study, we aimed to elucidate these characteristics among hospitalized smokers, a heretofore unstudied population.

METHODS

Cross-sectional data were collected from cigarette smokers via hospital bedside interviews. Participants reported e-cigarette use status, reasons for use (if used), e-cigarette advertising exposure, expected likelihood of future e-cigarette use, desire to quit smoking, and demographic characteristics.

RESULTS

Of the 657 English-speaking hospitalized smokers who provided data, 97% reported awareness of e-cigarettes and 46.4% reported e-cigarette use, with 20% reporting use in the previous 30 days. Previous e-cigarette use was significantly more likely among those who were White (odds ratio [OR] = 4.7; confidence interval [CI] = 3.2-6.7), were married/had a domestic partner (OR = 1.5; CI = 1.0-2.2), had more than a high school education (OR = 1.7; CI = 1.1-2.7), had e-cigarette advertising exposure (OR = 1.6; CI = 1.1-2.4), and were younger (OR = 1.3; CI = 1.1-1.5). Expected likelihood of future e-cigarette use was high and positively correlated with desire to quit smoking (Spearman's ρ = .18, p < .0001).

CONCLUSIONS

Rates of awareness and use of e-cigarettes may be elevated among hospitalized smokers, with more use reported among those who were White, younger, more educated, in a relationship, and exposed to e-cigarette advertising. The association between desire to quit smoking and expected likelihood of future e-cigarette use suggests that cigarette smokers may perceive e-cigarettes as a useful cessation aid.

Clinical management of tobacco dependence in inpatient psychiatry: provider practices and patient utilization

OBJECTIVE

This investigation examined predictors of utilization of nicotine replacement therapy (NRT) during a smoke-free psychiatric hospitalization.

METHODS

Smokers (N=324) were recruited from smoke-free adult inpatient psychiatric units. Exploratory analyses examined correlates of NRT provision and utilization.

RESULTS

The prevalence of NRT use was 51% overall and was greater among patients offered NRT on admission (58%) versus later (34%), among patients with more severe depression and nicotine withdrawal, and among those who reported perceptions that NRT decreases nicotine withdrawal, provides a nicotine substitute, and helps with quitting smoking (p<.05, all comparisons). Although the ratio of nicotine patch dose to usual cigarettes per day was 1.2±.7, the ratio was negatively correlated with time to first cigarette (Spearman's ρ=-.30, p<.01), suggesting potential underdosing of more dependent smokers.

CONCLUSIONS

During smoke-free psychiatric hospitalizations, clinical management of nicotine withdrawal may be enhanced by offering patients NRT directly on admission, educating patients on the benefits of NRT, and increasing the dosage for more dependent smokers.

Comprehensive assessment of the impact of cigarette smoking on survival of clear cell kidney cancer

PURPOSE

The impact of modifiable environmental factors on kidney cancer specific outcomes is under studied. We evaluated the impact of smoking exposure on cancer specific survival in patients with clear cell renal cell carcinoma treated with surgery.

MATERIALS AND METHODS

From a prospectively maintained database at a single center we collected the characteristics of 1,625 patients with clear cell renal cell carcinoma treated with surgery between 1995 through 2012. We determined the associations of smoking status with advanced disease, defined as AJCC (American Joint Committee on Cancer) stage greater than 2, and with cancer specific survival.

RESULTS

The prevalence rate of current, former and never smoking at diagnosis was 16%, 30% and 54%, respectively. Of the patients 62% reported a smoking history of 20 pack-years or greater. Median followup in survivors was 4.5 years (IQR 2.2-7.9). On univariable analysis a smoking history of 20 pack-years or greater was associated with a significantly increased risk of advanced disease (OR 1.43, 95% CI 1.02-2.00). However, it did not achieve an independent association after adjusting for age and gender. Pathological stage and Fuhrman grade adversely affected cancer specific survival on multivariable competing risks analysis. Although the association between smoking and cancer specific survival did not achieve statistical significance on multivariable analysis, the direction of the central estimate (HR 1.5, 95% CI 0.89-2.52) suggested that smoking adversely impacts cancer specific survival. Current smokers faced a higher risk of death from another cause than never smokers (HR 1.93, 95% CI 1.29-2.88).

CONCLUSIONS

Smoking exposure substantially increases the risk of death from another cause and adversely impacts cancer specific survival in patients with clear cell renal cell carcinoma. Treatment plans to promote smoking cessation are recommended for these patients.

Validity of self-reported adult secondhand smoke exposure

OBJECTIVES

Exposure of adults to secondhand smoke (SHS) has immediate adverse effects on the cardiovascular system and causes coronary heart disease. The current study evaluated brief self-report screening measures for accurately identifying adult cardiology patients with clinically significant levels of SHS exposure in need of intervention.

DESIGN AND SETTING

A cross-sectional study conducted in a university-affiliated cardiology clinic and cardiology inpatient service.

PATIENTS

Participants were 118 non-smoking patients (59% male, mean age=63.6 years, SD=16.8) seeking cardiology services.

MAIN OUTCOME MEASURES

Serum cotinine levels and self-reported SHS exposure in the past 24 h and 7 days on 13 adult secondhand exposure to smoke (ASHES) items.

RESULTS

A single item assessment of SHS exposure in one's own home in the past 7 days was significantly correlated with serum cotinine levels (r=0.41, p<0.001) with sensitivity ≥75%, specificity >85% and correct classification rates >85% at cotinine cut-off points of >0.215 and >0.80 ng/mL. The item outperformed multi-item scales, an assessment of home smoking rules, and SHS exposure assessed in other residential areas, automobiles and public settings. The sample was less accurate at self-reporting lower levels of SHS exposure (cotinine 0.05-0.215 ng/mL).

CONCLUSIONS

The single item ASHES-7d Home screener is brief, assesses recent SHS exposure over a week's time, and yielded the optimal balance of sensitivity and specificity. The current findings support use of the ASHES-7d Home screener to detect SHS exposure and can be easily incorporated into assessment of other major vital signs in cardiology.

Maternal and cord blood miR-223 expression associates with prenatal tobacco smoke exposure and low regulatory T-cell numbers

BACKGROUND

There is evidence that microRNAs (miRNAs) are sensitive to environmental stressors, including tobacco smoke. On the other hand, miRNAs are involved in immune regulation, such as regulatory T (Treg) cell differentiation. The aim of the present study was to investigate the association between prenatal tobacco smoke exposure, miRNAs, and Treg cell numbers.

METHODS

Within a prospective mother-child study (Lifestyle and Environmental Factors and Their Influence on Newborns Allergy Risk), we analyzed the expression of miR-155 and miR-223 together with Treg cell numbers in maternal blood during pregnancy, as well as in cord blood (n = 441). Tobacco smoke exposure was assessed based on questionnaire answers and maternal urine cotinine levels. Additionally, the concentration of smoking-related volatile organic compounds was measured in dwellings of study participants.

RESULTS

Both maternal and cord blood miR-223 expressions were positively correlated with maternal urine cotinine levels. An association was also found between maternal miR-223 expression and indoor concentrations of benzene and toluene. High miR-223 expression was associated with lower Treg cell numbers in maternal and cord blood. Furthermore, children with lower Treg cell numbers at birth had a higher risk of atopic dermatitis during the first 3 years of life. The concentration of the toluene metabolite S-benzylmercapturic acid in maternal urine was associated with decreased cord blood, but not maternal blood, miR-155 expression. A relationship between miR-155 expression and Treg cell numbers was not found.

CONCLUSIONS

For the first time, we show that maternal tobacco smoke exposure during pregnancy correlates with the level of miRNA-223 expression in blood, with an effect on children's cord blood Treg cell numbers and subsequent allergy risk.

The impact of smoking on pathologic response to neoadjuvant cisplatin-based chemotherapy in patients with muscle-invasive bladder cancer

PURPOSE

Smoking is the primary etiologic risk factor for bladder cancer and has been implicated in mechanisms of chemoresistance. We investigated smoking as a potential predictor for pathologic outcomes after neoadjuvant chemotherapy (NC) and radical cystectomy (RC) for muscle-invasive bladder cancer.

METHODS

We identified 139 patients treated with neoadjuvant cisplatin-based chemotherapy followed by RC for T2-4aN0M0 bladder cancer. Logistic regression was used to evaluate associations between smoking characteristics and pathologic outcomes (pT0, complete response; pT0/pTis/pT1, any response). In a secondary analysis, multivariate Cox regression was used to assess associations between smoking and recurrence-free and cancer-specific survival.

RESULTS

Our cohort consisted of 99 (71 %) males, with a median age of 65 (interquartile range 56, 71). Prevalence of never, former, and current smokers was 25, 45, and 29 %, respectively. In total, 63 patients experienced disease recurrence, 39 died of disease, and 11 died of other causes. There were no statistically significant associations between smoking characteristics and complete (p = 0.5) or any (p = 0.2) pathologic response to NC. Similarly, we did not find any association between smoking characteristics and recurrence (p = 0.6) or cancer-specific survival (p = 0.9).

CONCLUSIONS

In this series, smoking characteristics were not found to be predictive of pathologic response after NC and RC, although this analysis was limited by the small study sample size. However, the harmful effects of smoking warrants continued emphasis on smoking cessation counseling in bladder cancer patients.

Accuracy of self-reported tobacco use in newly diagnosed cancer patients

PURPOSE

Accurate identification of tobacco use is critical to implement evidence-based cessation treatments in cancer patients. The purpose of this study is to evaluate the accuracy of self-reported tobacco use in newly diagnosed cancer patients.

METHODS

Tobacco use questionnaires and blood samples were collected from 233 newly diagnosed cancer patients (77 lung, 77 breast, and 79 prostate cancer). Blood was analyzed for cotinine levels using a commercially available enzyme-linked immunosorbent assay. Patients with cotinine measurements exceeding 10 ng/mL were categorized as current smokers. Smoking status based upon cotinine levels was contrasted with self-report in current smokers, recent quitters (1 or less year since quit), non-recent quitters (>1 year since quit), and never smokers. Multivariate analyses were used to identify potential predictors of discordance between self-reported and biochemically confirmed smoking.

RESULTS

Cotinine confirmed 100 % accuracy in self-reporting of current and never smokers. Discordance in cotinine and smoking status was observed in 26 patients (15.0 %) reporting former tobacco use. Discordance in self-reported smoking was 12 times higher in recent (35.4 %) as compared with non-recent quitters (2.8 %). Combining disease site, pack-year history, and employment status predicted misrepresentation of tobacco use in 82.4 % of recent quitters.

CONCLUSIONS

Self-reported tobacco use may not accurately assess smoking status in newly diagnosed cancer patients. Patients who claim to have recently stopped smoking within the year prior to a cancer diagnosis and lung cancer patients may have a higher propensity to misrepresent tobacco use and may benefit from biochemical confirmation.

Determination of tobacco smoke exposure by plasma cotinine levels in infants and children attending urban public hospital clinics

OBJECTIVE To determine the prevalence of secondhand smoke (SHS) exposure among infants and young children who received preventive care at pediatric preventative care clinics associated with an urban public hospital. Cotinine, a metabolite of nicotine, has been used to study SHS exposure in population-based studies of children 3 years of age or older. DESIGN Retrospective study using a convenience sample. SETTING Urban county pediatric primary care clinics in San Francisco, California. PARTICIPANTS A total of 496 infants and children (mean [SD] age, 2.4 [1.9] years). INTERVENTIONS Discarded plasma samples (which were routinely collected for lead screening) were tested, and medical records were reviewed, for SHS exposure. MAIN OUTCOME MEASURE Secondhand smoke exposure based on cotinine plasma level and history of exposure in the medical record. RESULTS Thirteen percent of parents reported that their child was exposed to SHS, yet biochemical testing detected cotinine in 55% of samples, at a geometric mean (SD) of 0.23 (3.55) ng/mL. There were no significant sex or age differences. African American children had much higher mean cotinine levels than did Latino children (multiplicative factor change in cotinine, 6.01 ng/ml [95% Cl, 4.49-8.05 ng/ml] [correction]. CONCLUSION In a city with a low smoking rate (12%) and public smoking bans, we documented 55% exposure among infants and young children, using a plasma biomarker, compared with 13% exposure reported by parents. Because SHS is associated with significant respiratory diseases and parents underreport exposure, routine biochemical screening should be considered as a tool to identify and reduce SHS exposure.

Cotinine in human placenta predicts induction of gene expression in fetal tissues

Maternal cigarette smoking during pregnancy is associated with increased risk of perinatal morbidity and mortality. However, the mechanisms underlying adverse birth outcomes following prenatal exposure to cigarette smoke remain unknown due, in part, to the absence or unreliability of information regarding maternal cigarette smoke exposure during pregnancy. Our goal was to determine if placental cotinine could be a reliable biomarker of fetal cigarette smoke exposure during pregnancy. Cotinine levels were determined in placentas from 47 women who reported smoking during pregnancy and from 10 women who denied cigarette smoke exposure. Cotinine levels were significantly higher in placentas from women reporting cigarette smoking (median = 27.2 ng/g) versus women who reported no smoke exposure (2.3 ng/g, P < 0.001). Receiver operating characteristic curve analysis identified an optimal cut point of 7.5 ng/g (sensitivity = 78.7%, specificity = 100%) to classify placenta samples from mothers who smoked versus those from mothers who did not. Among 415 placentas for which maternal cigarette smoking status was unavailable, 167 had cotinine levels > 7.5 ng/g and would be considered positive for cigarette smoke exposure. Data from quantitative reverse-transcription polymerase chain reaction analyses demonstrated that in utero cigarette smoke exposure predicted by cotinine in placenta is associated with changes in the expression of xenobiotic-metabolizing enzymes in fetal tissues. CYP1A1 mRNA in fetal lung and liver tissue and CYP1B1 mRNA in fetal lung tissue were significantly induced when cotinine was detected in placenta. These findings indicate that cotinine in placenta is a reliable biomarker for fetal exposure and response to maternal cigarette smoking during pregnancy.

Asthma discordance in twins is linked to epigenetic modifications of T cells

T cells mediate the inflammatory responses observed in asthma among genetically susceptible individuals and have been suspected to be prone to epigenetic regulation. However, these relationships are not well established from past clinical studies that have had limited capacity to control for the effects of variable genetic predisposition and early environmental exposures. Relying on a cohort of monozygotic twins discordant for asthma we sought to determine if epigenetic modifications in T cells were associated with current asthma and explored whether such modifications were associated with second hand smoke exposures. Our study was conducted in a monozygotic twin cohort of adult twin pairs (n = 21) all discordant for asthma. Regulatory T cell (Treg) and effector T cell (Teff) subsets were assessed for levels of cellular function, protein expression, gene expression and CpG methylation within Forkhead box P3 (FOXP3) and interferon gamma-γ (IFNγ) loci. Comparisons by asthma and current report of exposure to second hand smoke were made. Treg from asthmatic discordant twins demonstrated decreased FOXP3 protein expression and impaired Treg function that was associated with increased levels of CpG methylation within the FOXP3 locus when compared to their non-asthmatic twin partner. In parallel, Teff from discordant asthmatic twins demonstrated increased methylation of the IFNγ locus, decreased IFNγ expression and reduced Teff function when compared to Teff from the non-asthmatic twin. Finally, report of current exposure to second hand smoke was associated with modifications in both Treg and Teff at the transcriptional level among asthmatics. The results of the current study provide evidence for differential function of T cell subsets in monozygotic twins discordant for asthma that are regulated by changes in DNA methylation. Our preliminary data suggest exposure to second hand smoke may augment the modified T cell responses associated with asthma.