Estimating the causal effect of filter ventilation levels in cigarettes on past 30-day smoking.

INTRODUCTION: Cigarettes with higher levels of filter ventilation are misperceived as less harmful and may be more appealing to consumers. Setting limits on filter ventilation has been considered as a policy, but a better understanding of any potential unintended consequences is needed. METHODS: Filter ventilation (0.2-61.1%) measured for 114 subbrands was merged with Wave 1 (2012-2013) of the Population Assessment of Tobacco Use and Health (PATH) data, restricted to adults 25+ years of age who smoked daily, and examined by quartiles. Inverse probability of exposure weights were used to estimate the causal effect of filter ventilation on past-30 day smoking at subsequent waves while accounting for potential confounders including demographics, menthol, heaviness of smoking and past quit attempts. RESULTS: Compared to those in the 1st (lowest) quartile of filter ventilation, those in the 2nd, 3rd and 4th quartiles had 1.02 (95% confidence interval: 0.57, 1.82), 0.86 (0.42, 1.73) and 1.52 (0.90, 2.56) times the odds of no past 30-day smoking at Wave 2 (approximately 1 year later, p=0.163), and 1.28 (0.80, 2.07), 1.11 (0.67, 1.83) and 1.65 (1.01, 1.24) times the odds of no past 30-day smoking at Wave 4 (3 years later, p = 0.238). CONCLUSIONS: This observational study found no strong evidence of a causal effect of filter ventilation on past 30-day smoking at approximately 1 and 3 years follow-up. However, our effect size estimates were not precise and thus an increase in the ability to quit smoking due to higher filter ventilation levels cannot be ruled out. IMPLICATIONS: Setting a maximum limit on filter ventilation (FV) in cigarettes could address the misperception that highly ventilated cigarettes are less harmful and the link between FV and lung adenocarcinoma. It is important to understand whether such a policy would have unintended consequences on longer-term smoking behavior. We found no strong evidence that FV affects past 30-day smoking 1-3 years later, but could not rule out the possibility that higher FV increases cessation rates. If future studies confirm these epidemiologic findings, this could mean that setting a limit on FV would not lead to reductions in the ability to quit smoking.

Selective Reduction of Socioeconomic Disparities in the Experimental Tobacco Marketplace: Effects of Cigarette and E-cigarette Flavor Restrictions.

INTRODUCTION: Cigarette smoking accounts for >30% of the socioeconomic gap in life expectancy. Flavored restrictions claim to promote equity; however, no previous studies have compared the effect of cigarette and e-cigarette flavor restrictions among individuals who smoke with lower and higher socioeconomic status (SES). AIMS AND METHODS: In a between-group within-subject design, individuals with lower (n = 155) and higher (n = 125) SES completed hypothetical purchasing trials in the experimental tobacco marketplace (ETM). Conditions were presented in a 2 × 2 factorial design (cigarette flavors restricted or unrestricted and e-cigarette flavors restricted or unrestricted) with increasing cigarette prices across trials. RESULTS: Results show (1) SES differences in cigarette, e-cigarette, and NRT purchases under unrestricted policies, with lower SES showing higher cigarette demand and lower e-cigarette and NRT substitution than higher SES, (2) cigarette restrictions decreased cigarette and increased NRT purchases among lower SES, but no significant changes among higher SES, (3) decreased SES differences in cigarette demand under cigarette restrictions, but persistence under e-cigarette restrictions or their combination, (4) persistence of SES differences in e-cigarette purchases when all restrictions were enforced, and (5) waning of SES differences in NRT purchasing under all restrictions. CONCLUSIONS: Flavor restrictions differentially affected individuals based on SES. Within-group comparisons demonstrated restrictions significantly impacted lower SES, but not higher SES. Between-group comparisons showed SES differences in cigarette purchasing decreased under cigarette restrictions, but persisted under e-cigarette-restrictions or their combination. Additionally, SES differences in NRT substitution decreased under flavor restrictions. These findings highlight the utility of the ETM to investigate SES disparities. IMPLICATIONS: With increasing trends of socioeconomic differences in smoking prevalence and cessation rates, smoking-related health disparities are expected to continue to widen. Restricting menthol flavor in cigarettes while enhancing the availability and affordability of NRT have the potential to alleviate SES disparities in tobacco use, therefore, positively impacting health equity. However, this effect may depend on flavor availability in other tobacco products.

Sex-related DNA methylation is associated with inflammation and gene expression in the lungs of healthy individuals.

Lung cancer exhibits sex-biased molecular characteristics and epidemiological trends, suggesting a need for sex-specific approaches to understanding its etiology and treatment. DNA methylation alterations play critical roles in lung carcinogenesis and may serve as valuable biomarkers for precision medicine strategies. We employed the Infinium MethylationEPIC array to identify autosomal sex-related differentially methylated CpG sites (DM-CpGs) in lung epithelium of healthy individuals (32 females and 37 males) while controlling for age, BMI, and tobacco use. We correlated DM-CpGs with gene expression in lung epithelium and immune responses in bronchoalveolar lavage. We validated these DM-CpGs in lung tumors and adjacent normal tissue from The Cancer Genome Atlas (TCGA). Among 522 identified DM-CpGs, 61% were hypermethylated in females, predominantly located in promoter regions. These DM genes were implicated in cell-to-cell signaling, cellular function, transport, and lipid metabolism. Correlation analysis revealed sex-specific patterns between DM-CpGs and gene expression. Additionally, several DM-CpGs were correlated significantly with cytokines (IL-1ß, IL-4, IL-12p70, and IFN-γ), macrophage, and lymphocyte counts. Also, some DM-CpGs were observed in TCGA lung adenocarcinoma, squamous cell carcinoma, and adjacent normal tissues. Our findings highlight sex-specific DNA methylation patterns in healthy lung epithelium and their associations with lung gene expression and lung immune biomarkers. These findings underscore the potential role of lung sex-related CpGs as epigenetic predispositions influencing sex disparities in lung cancer risk and outcomes, warranting further investigation for personalized lung cancer management strategies.

mRNA vaccines against SARS-CoV-2 induce divergent antigen-specific T-cell responses in patients with lung cancer.

BACKGROUND: The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) Omicron variant is highly transmissible and evades pre-established immunity. Messenger RNA (mRNA) vaccination against ancestral strain spike protein can induce intact T-cell immunity against the Omicron variant, but efficacy of booster vaccination in patients with late-stage lung cancer on immune-modulating agents including anti-programmed cell death protein 1(PD-1)/programmed death-ligand 1 (PD-L1) has not yet been elucidated. METHODS: We assessed T-cell responses using a modified activation-induced marker assay, coupled with high-dimension flow cytometry analyses. Peripheral blood mononuclear cells (PBMCs) were stimulated with various viral peptides and antigen-specific T-cell responses were evaluated using flow cytometry. RESULTS: Booster vaccines induced CD8+ T-cell response against the ancestral SARS-CoV-2 strain and Omicron variant in both non-cancer subjects and patients with lung cancer, but only a marginal induction was detected for CD4+ T cells. Importantly, antigen-specific T cells from patients with lung cancer showed distinct subpopulation dynamics with varying degrees of differentiation compared with non-cancer subjects, with evidence of dysfunction. Notably, female-biased T-cell responses were observed. CONCLUSION: We conclude that patients with lung cancer on immunotherapy show a substantial qualitative deviation from non-cancer subjects in their T-cell response to mRNA vaccines, highlighting the need for heightened protective measures for patients with cancer to minimize the risk of breakthrough infection with the Omicron and other future variants.

Smokers Awareness and Risk Perceptions of Filter Ventilation.

Objectives: The addition of tiny rows of holes in the tipping paper (filter ventilation) of cigarettes allows air to mix with the smoke, which can change risk perceptions. In this study, we examine smokers' knowledge and beliefs about filter ventilation. Methods: Web-based panel surveys conducted in 2016 and 2017 of current adult cigarette smokers (N = 2355) provided data on awareness and understanding of filter vents in their cigarettes, whether they believed blocking the holes would change the taste of their cigarettes, and their perceptions about their future risk of being diagnosed with lung cancer. The most commonly used cigarette brands reported by participants also were characterized on the presence and level of ventilation holes. Results: Approximately 40% of participants (mostly younger and male) reported awareness of the filter ventilation in their cigarettes. Only 30% of the participants were both aware of and understood the function of filter ventilation; they also were significantly more likely to worry about developing lung cancer. Conclusion: Although misleading descriptors associated with filter ventilation are prohibited, most smokers still smoked cigarettes with filter vents, and many are unaware and misunderstand the potential risks of filter ventilation.