Effects of educational interventions based on the theory of planned behavior on oral cancer-related knowledge and tobacco smoking in adults: a cluster randomized controlled trial.

BACKGROUND: The theory of planned behavior (TPB) is an effective model for facilitating behavioral change. The aim of the present study was to evaluate the impact of TPB-based educational interventions on oral cancer-related knowledge and tobacco smoking behavior in an Iranian adult population in 2022. METHODS: In this randomized controlled trial, a total of 400 healthy individuals were enrolled. The study was implemented in 20 urban health centers in the south of Tehran, Iran. The health centers were randomly allocated into two intervention groups. In group PowerPoint (PP), the participants received education through a 20-minute PowerPoint presentation complemented by a pamphlet. Group WhatsApp (WA) was educated via WhatsApp messages and images. Data was collected using a structured questionnaire at baseline, and at one- and three-month follow-ups. The outcomes were evaluated in terms of knowledge, tobacco smoking behavior, and the related model constructs i.e. intention, attitude, subjective norm, and perceived behavioral control. Generalized estimating equations (GEE) regression models were applied to assess the effect of interventions on repeated measurements of the outcomes. All analyses were conducted using STATA Software Version 17. RESULTS: Out of all the participants, 249 (62%) were women. The mean and standard deviation (SD) of age were 39.67 and 13.80 years. Overall, group PP had a significantly higher score of knowledge compared to group WA (ß = 0.43, p = 0.005). No significant differences were found between the groups with regard to tobacco smoking and the related TPB constructs, except for attitude with a higher score in group PP compared to group WA (ß = 0.50, p = 0.004). At the three-month follow-up, both interventions had significant effects on increasing knowledge (ß = 4.41), decreasing tobacco smoking (OR = 0.54), and increasing intention (ß = 1.11), attitude (ß = 1.22), subjective norm (ß = 1.37), and perceived behavioral control (ß = 1.08) (P < 0.001). CONCLUSIONS: Both interventions were effective in improving knowledge, tobacco smoking, and the TPB constructs after three months. Therefore, the application of both methods could be considered in the design and implementation of oral cancer prevention programs. TRIAL REGISTRATION: The trial protocol was registered in the Iranian Registry of Clinical Trials (IRCT) on 04/03/2022 (registration number: IRCT20220221054086N1).

Factors Influencing Tobacco Smoking and Cessation Among People Living with HIV: A Systematic Review and Meta-analysis.

Tobacco smoking is highly prevalent among people living with HIV (PLWH), yet there is a lack of data on smoking behaviours and effective treatments in this population. Understanding factors influencing tobacco smoking and cessation is crucial to guide the design of effective interventions. This systematic review and meta-analysis of studies conducted in both high-income (HICs) and low- and middle-income countries (LMICs) synthesised existing evidence on associated factors of smoking and cessation behaviour among PLWH. Male gender, substance use, and loneliness were positively associated with current smoking and negatively associated with smoking abstinence. The association of depression with current smoking and lower abstinence rates were observed only in HICs. The review did not identify randomised controlled trials conducted in LMICs. Findings indicate the need to integrate smoking cessation interventions with mental health and substance use services, provide greater social support, and address other comorbid conditions as part of a comprehensive approach to treating tobacco use in this population. Consistent support from health providers trained to provide advice and treatment options is also an important component of treatment for PLWH engaged in care, especially in LMICs.

Lower dorsal putamen D2/3 receptor availability and amphetamine-induced dopamine release are related to poorer cognitive function in recently abstinent people who smoke and healthy controls.

INTRODUCTION: In the dopamine system, the mesolimbic pathway, including the dorsal striatum, underlies the reinforcing properties of tobacco smoking, and the mesocortical pathway, including the dorsolateral prefrontal cortex (dlPFC), is critical for cognitive functioning. Dysregulated dopamine signaling has been linked to drug-seeking behaviors and cognitbie deficits. The dorsal striatum and dlPFC are structurally and functionally connected and are the key regions for cognitive functioning. We recently showed that people who smoke have lower dlPFC dopamine (D2/3R) receptor availability than people who do not, which is related to poorer cognitive function. The goal of this study was to examine the same brain-behavior relationship in the dorsal striatum. METHODS: Twenty-nine (18 males) recently abstinent people who smoke and twenty-nine sex-matched healthy controls participated in two same-day [11C]-(+)-PHNO positron emission tomography scans before and after amphetamine administration to provoke dopamine release. D2/3R availability (binding potential; BPND) and amphetamine-induced dopamine release (%ΔBPND) were calculated. Cognition (verbal learning and memory) was assessed with the CogState computerized battery. RESULTS: There were no group differences in baseline BPND. People who smoke have a smaller magnitude %ΔBPND in dorsal putamen than healthy controls (p=0.022). People who smoke perform worse on immediate (p=0.035) and delayed (p=0.011) recall than healthy controls. In all people, lower dorsal putamen BPND was associated with worse immediate (p=0.006) and delayed recall (p=0.049), and lower %ΔBPND was related to worse delayed recall (p=0.022). CONCLUSION: Lower dorsal putamen D2/3R availability and function are associated with disruptions in cognitive function that may underlie difficulty with resisting smoking. IMPLICATIONS: This study directly relates dopamine imaging outcomes in the dorsal striatum to cognitive function in recently abstinent people who smoke cigarettes and healthy controls. The current work included a well-characterized subject sample in terms of demographics, smoking characteristics, and a validated neurocognitive test of verbal learning and memory. The findings of this study extend previous literature relating dopamine imaging outcomes to cognition in recently abstinent people who smoke and people who do not smoke, expanding our understanding of brain-behavior relationships.

Smoking may increase the usage of antidepressant: evidence from genomic perspective analysis.

This study uses the two-sample Mendelian randomization (TSMR) method to explore the causal relationships between smoking initiation (SMKI), never smoking (NSMK), past tobacco smoking (PTSMK), and the usage of antidepressants (ATD). Single-nucleotide polymorphisms (SNPs) with genome-wide significance (P < 5E-08) related to SMKI, NSMK, and PTSMK were selected from the genome-wide association study (GWAS) database as instrumental variables (IVs). The main method, inverse variance weighted (IVW), was utilized to investigate the causal relationship. The results demonstrated a positive causal relationship between SMKI and ATD use, where SMKI leads to an increase in ATD use. Conversely, NSMK and PTSMK showed a negative causal relationship with ATD use, meaning that NSMK and PTSMK lead to a reduction in ATD use. Additionally, sensitivity analysis showed that the results of this study were robust and reliable. Using the TSMR method and from a genetic perspective, this study found that SMKI leads to an increase in ATD use, while NSMK and PTSMK reduce ATD use.

Effects of firsthand tobacco smoking on retinal vessel caliber: a systematic review and meta-analysis.

PURPOSE: To review the effects of firsthand tobacco smoking on central retinal arteriolar equivalent (CRAE) and central retinal venular equivalent (CRVE) of firsthand tobacco smokers. METHODS: We performed a search on EMBASE and PubMed for studies up to 15th July 2022. Two independent reviewers selected studies with baseline data of CRAE and CRVE of current smokers, nonsmokers, and former smokers. Initial search identified 893 studies, of which 10 were included in the meta-analysis. Two independent reviewers extracted data from the included studies. The quality of studies was assessed by the Newcastle-Ottawa Scale. RESULTS: In this meta-analysis, 7431 nonsmokers, 2448 current smokers and 5786 former smokers, as well as 7404 nonsmokers, 2430 current smokers and 5763 former smokers were included in CRAE and CRVE analysis respectively. Nonsmokers had narrower CRVE (Weighted mean difference [WMD], -12.15; 95% CI, -17.33 - -6.96) and CRAE (WMD, -4.77; 95% CI, -7.96 - -1.57) than current smokers, and narrower CRVE (WMD, -3.08; 95% CI, -6.06 - -0.11) than former smokers. Current smokers had wider CRVE (WMD, 10.42; 95% CI, 7.80 - 13.04) and CRAE (WMD, 7.05; 95% CI, 6.65 - 7.46) than former smokers. Subgroup analysis and sensitivity analysis were performed. CONCLUSION: Firsthand tobacco smoking resulted in wider CRAE and CRVE in current and former smokers, particularly in CRVE, and such changes may not be reversible after smoking cessation. Therefore, retinal vessel caliber may reflect the effects of firsthand tobacco smoking and be used to estimate the risk of cardiovascular diseases.

Preventing smoking initiation in adolescents living in vulnerable socioeconomic conditions: Study protocol of the KickAsh!-intervention.

AIMS: Adolescents living in vulnerable socioeconomic conditions are confronted with tobacco-related health disparities. As school-based interventions appear to be less effective among these youngsters, other approaches are necessary. One promising avenue is youth social work settings that offer sport and recreational activities (SR-settings). SR-settings have been examined as a levering context for health promotion, but evidence regarding smoking prevention is currently lacking. METHODS: This study describes the protocol of a non-randomised cluster controlled trial evaluating a smoking prevention intervention for adolescents. At least 24 SR-settings are needed for the intervention and control group. A mixed-method design will be used. Quantitative measures will be used to assess effectiveness, involving validated questionnaires on smoking initiation behaviour and influencing factors (i.e. attitude, self-efficacy, social influence and risk perception). In addition, feasibility will be assessed with regard to intervention fidelity, dose and reach. Data will be collected at baseline, three and nine months following the intervention. To gain deeper understanding on the impact and underlying processes of the intervention, we will conduct qualitative interviews with users (adolescents) and implementers (youth workers within the SR-settings) of the intervention. CONCLUSIONS: Conducting this trial will offer novel insights into the effectiveness of a smoking prevention intervention designed for adolescents living in vulnerable socioeconomic conditions. A mixed-method design will enable to measure impact, implementation and underlying processes of the intervention. Overall, this design will enhance our understanding on the suitability of SR-settings as contexts for smoking prevention initiatives targeting hard-to-reach youth. This trial is registered on Clinicaltrials.gov: NCT05920772.

Short-term effectiveness of the national German quitline for smoking cessation: results of a randomized controlled trial.

BACKGROUND: The objective of the present study was to examine the short-term effectiveness of the national German quitline for smoking cessation. METHODS: A parallel-group, two-arm, superiority, randomized controlled trial with data collection at baseline and post-intervention (three months from baseline) was conducted. Individuals were randomized to either the intervention group, receiving up to six telephone counselling calls, or the control group, receiving an active control intervention (self-help brochure). The primary outcome was the seven-day point prevalence abstinence at post-assessment. Secondary outcomes included changes in smoking-related cognitions and coping strategies from pre- to post-assessment, the perceived effectiveness of intervention components, and the satisfaction with the intervention. RESULTS: A total of n = 905 adult daily smokers were assigned to either the intervention group (n = 477) or the control group (n = 428). Intention-to-treat analyses demonstrated that individuals allocated to the telephone counselling condition were more likely to achieve seven-day point prevalence abstinence at post-assessment compared to those allocated to the self-help brochure condition (41.1% vs. 23.1%; OR = 2.3, 95% CI [1.7, 3.1]). Participants who received the allocated intervention in both study groups displayed significant improvements in smoking-related cognitions and coping strategies with the intervention group showing greater enhancements than the control group. This pattern was also found regarding the perceived effectiveness of intervention components and the satisfaction with the intervention. CONCLUSION: The present study provides first empirical evidence on the short-term effectiveness of the national German quitline for smoking cessation, highlighting its potential as an effective public health intervention to reduce the burden of disease associated with smoking. TRIAL REGISTRATION: This study is registered in the German Clinical Trials Register (DRKS00025343). Date of registration: 2021/06/07.

Examining temporal trends in psychological distress and the co-occurrence of common substance use in a population-based sample of grade 7-12 students from 2013 to 2019.

PURPOSE: Characterizing trends and correlates of adolescent psychological distress is important due to observed global increases over the last 20 years. Substance use is a commonly discussed correlate, though we lack an understanding about how co-occurrence of these concerns has been changing over time. METHODS: Data came from repeated, representative, cross-sectional surveys of grade 7-12 students across Ontario, Canada conducted biennially from 2013 to 2019. Poisson regression with robust standard errors was used to examine changes in the joint association between psychological distress (operationalized as Kessler-6 [K6] scores ≥ 13) and substance use over time. Weighted prevalence ratios (PR) and their 99% confidence intervals were estimated, where p < 0.01 denotes statistical significance. RESULTS: The prevalence of psychological distress doubled between 2013 and 2019, with adjusted increases of about 1.2 times each survey year. This biennial increase did not differ based on sex, perceived social standing, school level, or any substance use. Students using substances consistently reported a higher prevalence of psychological distress (between 1.2 times and 2.7 times higher). There were similarly no differential temporal trends based on substance use for very high distress (K6 ≥ 19) or K6 items explored individually. CONCLUSION: Psychological distress steeply increased among adolescents and substance use remains important to assess and address alongside distress. However, the magnitude of temporal increases appears to be similar for adolescents reporting and not reporting substance use.

Associations between tobacco smoking status and patch test results-A cross-sectional pilot study from the Information Network of Departments of Dermatology (IVDK).

BACKGROUND: Earlier studies suggested a potential association between tobacco smoking and nickel sensitization, but little is known about other contact allergens. OBJECTIVES: To investigate the association of smoking status and contact sensitizations as well as subtypes of dermatitis, and to analyse the sensitization profiles of tobacco smokers. PATIENTS AND METHODS: Within the Information Network of Departments of Dermatology (IVDK), we performed a cross-sectional multicentre pilot study comprising 1091 patch-tested patients from 9 departments, comparing 541 patients with a history of cigarette smoking (281 current and 260 former smokers) with 550 never-smokers. RESULTS: We could not confirm the previously reported association between nickel sensitization and tobacco smoking. Moreover, sensitizations to other allergens, including colophony, fragrance mix I, Myroxylon pereirae and formaldehyde, were not increased in cigarette smokers compared with never smokers. Hand dermatitis (50.6% vs. 33.6%) and occupational cause (36.2% vs. 22.5%) were significantly more frequent among cigarette smokers compared with never-smokers as shown by non-overlapping 95% confidence intervals. CONCLUSIONS: Although our study does not allow a firm conclusion on whether smoking status contributes to certain contact sensitizations, it confirms an association of smoking with hand dermatitis and occupational cause.

Screening, brief intervention, and referral to treatment for tobacco consumption, alcohol misuse, and physical inactivity: an equity-informed rapid review.

OBJECTIVE: This rapid review systematically synthesizes evidence of the effectiveness of the Screening, Brief Intervention, and Referral (SBIR/T) approach for tobacco use, alcohol misuse, and physical inactivity. STUDY DESIGN: This was a rapid review. METHODS: We searched primary studies between 2012 and 2022 in seven electronic databases. The search strategy used concepts related to alcohol-related disorders, intoxication, cigarette, nicotine, physical activity, exercise, sedentary, screening, therapy, and referral. We reviewed both title/abstract and full-text using a priori set inclusion and exclusion criteria to identify the eligible studies. We appraised study quality, extracted data, and summarized the characteristics of the included studies. We applied health equity lenses in the synthesis. RESULTS: Of the 44 included studies, most focused on alcohol misuse. SBIR/T improved patients' attitudes toward alcohol behavior change, improved readiness and referral initiation for change, and effectively reduced alcohol consumption. Few studies pertained to smoking and physical inactivity. Most studies on smoking demonstrated effectiveness pertaining to patients' acceptance of referral recommendations, improved readiness and attempts to quitting smoking, and reduced or cessation of smoking. Findings were mixed about the effectiveness of SBIR/T in improving physical activity. Minimal studies exist on the impacts of SBIR/T for these three risk factors on healthcare resource use or costs. Studies considering diverse population characteristics in the design and effectiveness assessment of the SBIR/T intervention are lacking. CONCLUSIONS: More research on the impacts of SBIR/T on tobacco use, alcohol misuse, and physical inactivity is required to inform the planning and delivery of SBIR/T for general and disadvantaged populations.

Social networks of people with serious mental illness who smoke: potential role in a smoking cessation intervention.

BACKGROUND: Smoking is a major contributor to morbidity and mortality among individuals with serious mental illness (SMI) and social networks may play an important role in smoking behaviors. AIMS: Our objectives were to (1) describe the network characteristics of adults with SMI who smoke tobacco (2) explore whether network attributes were associated with nicotine dependence. METHODS: We performed a secondary analysis of baseline data from a tobacco smoking cessation intervention trial among 192 participants with SMI. A subgroup (n = 75) completed questions on the characteristics of their social network members. The network characteristics included network composition (e.g. proportion who smoke) and network structure (e.g. density of connections between members). We used multilevel models to examine associations with nicotine dependence. RESULTS: Participant characteristics included: a mean age 50 years, 49% women, 48% Black, and 41% primary diagnosis of schizophrenia/schizoaffective disorder. The median personal network proportion of active smokers was 22%, active quitters 0%, and non-smokers 53%. The density of ties between actively smoking network members was greater than between non-smoking members (55% vs 43%, p = .02). Proportion of network smokers was not associated with nicotine dependence. CONCLUSIONS: We identified potential social network challenges and assets to smoking cessation and implications for network interventions among individuals with SMI.

The contribution of smoking and smokeless tobacco to oesophageal squamous cell carcinoma risk in the African oesophageal cancer corridor: Results from the ESCCAPE multicentre case-control studies.

Tobacco use is a well-established risk factor for oesophageal squamous cell carcinoma (ESCC) but the extent of its contribution to the disease burden in the African oesophageal cancer corridor has not been comprehensively elucidated, including by type of tobacco use. We investigated the contribution of tobacco use (smoking and smokeless) to ESCC in Tanzania, Malawi and Kenya. Hospital-based ESCC case-control studies were conducted in the three countries. Incident cases and controls were interviewed using a comprehensive questionnaire which included questions on tobacco smoking and smokeless tobacco use. Logistic regression models were used to estimate odds ratios (OR) and their 95% confidence intervals (CI) of ESCC associated with tobacco, adjusted for age, sex, alcohol use, religion, education and area of residence. One thousand two hundred seventy-nine cases and 1345 controls were recruited between August 5, 2013, and May 24, 2020. Ever-tobacco use was associated with increased ESCC risk in all countries: Tanzania (OR 3.09, 95%CI 1.83-5.23), and in Malawi (OR 2.45, 95%CI 1.80-3.33) and lesser in Kenya (OR 1.37, 95%CI 0.94-2.00). Exclusive smokeless tobacco use was positively associated with ESCC risk, in Tanzania, Malawi and Kenya combined (OR 1.92, 95%CI 1.26-2.92). ESCC risk increased with tobacco smoking intensity and duration of smoking. Tobacco use is an important risk factor of ESCC in Tanzania, Malawi and Kenya. Our study provides evidence that smoking and smokeless tobacco cessation are imperative in reducing ESCC risk.

Cross-talks between gut microbiota and tobacco smoking: a two-sample Mendelian randomization study.

BACKGROUND: Considerable evidence has been reported that tobacco use could cause alterations in gut microbiota composition. The microbiota-gut-brain axis also in turn hinted at a possible contribution of the gut microbiota to smoking. However, population-level studies with a higher evidence level for causality are lacking. METHODS: This study utilized the summary-level data of respective genome-wide association study (GWAS) for 211 gut microbial taxa and five smoking phenotypes to reveal the causal association between the gut microbiota and tobacco smoking. Two-sample bidirectional Mendelian randomization (MR) design was deployed and comprehensively sensitive analyses were followed to validate the robustness of results. We further performed multivariable MR to evaluate the effect of neurotransmitter-associated metabolites on observed associations. RESULTS: Our univariable MR results confirmed the effects of smoking on three taxa (Intestinimonas, Catenibacterium, and Ruminococcaceae, observed from previous studies) with boosted evidence level and identified another 13 taxa which may be causally affected by tobacco smoking. As for the other direction, we revealed that smoking behaviors could be potential consequence of specific taxa abundance. Combining with existing observational evidence, we provided novel insights regarding a positive feedback loop of smoking through Actinobacteria and indicated a potential mechanism for the link between parental smoking and early smoking initiation of their children driven by Bifidobacterium. The multivariable MR results suggested that neurotransmitter-associated metabolites (tryptophan and tyrosine, also supported by previous studies) probably played a role in the action pathway from the gut microbiota to smoking, especially for Actinobacteria and Peptococcus. CONCLUSIONS: In summary, the current study suggested the role of the specific gut microbes on the risk for cigarette smoking (likely involving alterations in metabolites) and in turn smoking on specific gut microbes. Our findings highlighted the hazards of tobacco use for gut flora dysbiosis and shed light on the potential role of specific gut microbiota for smoking behaviors.

Gender differences in smoking-induced changes in the tumor immune microenvironment.

Both gender and smoking are correlated with prevalence and outcomes in many types of cancers. Tobacco smoke is a known carcinogen through its genotoxicity but can also affect cancer progression through its effect on the immune system. In this study, we aim to evaluate the hypothesis that the effects of smoking on the tumor immune microenvironment will be influenced differently by gender using large-scale analysis of publicly available cancer datasets. We used The Cancer Genomic Atlas (TCGA) datasets (n = 2724) to analyze effects of smoking on different cancer immune subtypes and the relative abundance of immune cell types between male and female cancer patients. We further validated our results by analyzing additional datasets, including Expression Project for Oncology (expO) bulk RNA-seq dataset (n = 1118) and single-cell RNA-seq dataset (n = 14). Results of our study indicate that in female patients, two immune subtypes, C1 and C2, are respectively over and under abundant in smokers vs. never smokers. In males, the only significant difference is underabundance of the C6 subtype in smokers. We identified gender-specific differences in the population of immune cell types between smokers and never smokers in all TCGA and expO cancer types. Increased plasma cell population was identified as the most consistent feature distinguishing smokers and never smokers, especially in current female smokers based on both TCGA and expO data. Our analysis of existing single-cell RNA-seq data further revealed that smoking differentially affects the gene expression profile of cancer patients based on the immune cell type and gender. In our analysis, female and male smokers show different smoking-induced patterns of immune cells in tumor microenvironment. Besides, our results suggest cancer tissues directly exposed to tobacco smoke undergo the most significant changes, but all other tissue types are affected as well. Findings of current study also indicate that changes in the populations of plasma cells and their correlations to survival outcomes are stronger in female current smokers, with implications for cancer immunotherapy of women smokers. In conclusion, results of this study can be used to develop personalized treatment plans for cancer patients who smoke, particularly women smokers, taking into account the unique immune cell profile of their tumors.

Heme metabolism mediates the effects of smoking on gut microbiome.

INTRODUCTION: The number of smokers worldwide increased greatly during the past decades and reached 1.14 billion in 2019, becoming a leading risk factor for human health. Tobacco smoking has wide effects on human genetics, epigenetics, transcriptome, and gut microbiome. Although many studies have revealed effects of smoking on host transcriptome, research on the relationship among smoking, host gene expression, and the gut microbiome is limited. METHODS: We first explored transcriptome and metagenome profile differences between smokers and non-smokers. To evaluate the relationship between host gene expression and gut microbiome, we then applied bi-directional mediation analysis to infer causal relationships between smoking, gene expression, and gut microbes. RESULTS: Metagenome and transcriptome analyses revealed 71 differential species and 324 differential expressed genes between smokers and non-smokers. With smoking as an exposure variable, we identified 272 significant causal relationships between gene expression and gut microbes, among which there were 247 genes that mediate the effect of smoking on gut microbes. Pathway-based enrichment analysis showed that these genes were significantly enriched in heme metabolic pathway, which mainly mediated the changes of Bacteroides finegoldii and Lachnospiraceae bacterium 9_1_43BFAA. Additionally, by performing metabolome data analysis in the Integrated Human Microbiome project (iHMP) database, we verified the correlation between the intermediate products of the heme metabolism pathway (porphobilinogen, bilirubin, and biliverdin) and gut microbiome. CONCLUSIONS: By investigating the bi-directional interaction between smoking-related host gene expression and gut microbes, this study provided evidence for the mediation of smoking on gut microbes through co-involvement or interaction of heme metabolism. IMPLICATIONS: By comparing the metagenome and transcriptome sequencing profiles between 34 smokers and 33 age- and gender-matched non-smokers, we are the first to reveal causal relationships among tobacco smoking, host gene expression and gut microbes. These findings offer insight into how smoking affects gut microbes through host gene expression and metabolism, which highlights the importance of heme metabolism in modulating the effects of smoking on gut microbiome.

Dose-response Relationships Between Cigarette Smoking and Breast Cancer Risk: A Systematic Review and Meta-analysis.

BACKGROUND: The possible association between cigarette smoking and breast cancer risk has been quite controversial. METHODS: We conducted a systematic review and meta-analysis of all available observational studies published on the issue up to January 2020. Random-effects models were used to compute pooled relative risks (RRs) for cigarette smoking status and dose-risk relationships were evaluated using one-stage random-effects dose-response models. RESULTS: A total of 169 studies were selected, providing a pooled RR for breast cancer of 1.07 (95% confidence interval [CI], 1.05-1.10) for current, 1.08 (95% CI, 1.06-1.10) for former, and 1.09 (95% CI, 1.07-1.11) for ever smokers, compared to never smokers. Results were consistent in case-control and cohort studies. No meaningful differences were observed across strata of most covariates considered, nor according to relevant genetic mutations and polymorphisms (ie, BRCA mutation, N-acetyltransferase and glutathione S-transferase genotypes, and P53). Breast cancer risk increased linearly with intensity of smoking (RR 1.12; 95% CI, 1.08-1.16 for 20 cigarettes/day and 1.26; 95% CI, 1.17-1.36 for 40 cigarettes/day), and with increasing duration of smoking (RR 1.05; 95% CI, 1.03-1.08 for 20 years of smoking and 1.11; 95% CI, 1.06-1.16 for 40 years of smoking). CONCLUSION: The present large and comprehensive meta-analysis-conducted using an innovative approach for study search-supports the evidence of a causal role of tobacco smoking on breast cancer risk.

The Association of Tobacco Smoking, Second-hand Smoke, and Novel Tobacco Products With COVID-19 Severity and Mortality in Italy: Results From the COSMO-IT Study.

BACKGROUND: Despite the robust evidence of an excess risk of coronavirus disease 2019 (COVID-19) severity and mortality in ever smokers, the debate on the role of current and ex-smokers on COVID-19 progression remains open. Limited or no data are available on the link between electronic cigarette (e-cigarette), heated tobacco product (HTP) and second-hand smoke (SHS) exposure and COVID-19 progression. To fill this knowledge gap, we undertook the COvid19 and SMOking in ITaly (COSMO-IT) study. METHODS: A multi-centre longitudinal study was conducted in 2020-2021 in 24 Italian hospitals on a total of 1,820 laboratory-confirmed COVID-19 patients. We estimated multivariable odds ratios (OR) and 95% confidence intervals (CI) to quantify the association between smoking-related behaviours (ie, smoking status, e-cigarette and HTP use, and SHS exposure) and COVID-19 severity (composite outcome: intubation, intensive care unit admission and death) and mortality. RESULTS: Compared to never smokers, current smokers had an increased risk of COVID-19 mortality (OR 2.17; 95% CI, 1.06-4.41). E-cigarette use was non-significantly associated to an increased risk of COVID-19 severity (OR 1.60; 95% CI, 0.96-2.67). An increased risk of mortality was observed for exposure to SHS among non-smokers (OR 1.67; 95% CI, 1.04-2.68), the risk being particularly evident for exposures of ≥6 hours/day (OR 1.99; 95% CI, 1.15-3.44). CONCLUSION: This multicentric study from Italy shows a dismal COVID-19 progression in current smokers and, for the first time, in SHS exposed non-smokers. These data represent an additional reason to strengthen and enforce effective tobacco control measures and to support smokers in quitting.

Tobacco smoke exacerbates Filifactor alocis pathogenicity.

AIM: Filifactor alocis has recently emerged as a periodontal pathobiont that appears to thrive in the oral cavity of smokers. We hypothesized that identification of smoke-responsive F. alocis genes would provide insight into adaptive strategies and that cigarette smoke would enhance F. alocis pathogenesis in vivo. MATERIALS AND METHODS: F. alocis was grown in vitro and cigarette smoke extract-responsive genes determined by RNAseq. Mice were exposed, or not, to mainstream 1R6F research cigarette smoke and infected with F. alocis, or not, in an acute ligature model of periodontitis. Key clinical, infectious, and immune data were collected. RESULTS: In culture, F. alocis growth was unaffected by smoke conditioning and only a small number of genes were specifically regulated by smoke exposure. Reduced murine mass, differences in F. alocis-cognizant antibody production, and altered immune profiles as well as altered alveolar bone loss were all attributable to smoke exposure and/or F. alocis infection in vivo. CONCLUSIONS: F. alocis is well-adapted to tobacco-rich conditions and its pathogenesis is enhanced by tobacco smoke exposure. A smoke-exposed ligature model of periodontitis shows promise as a tool with which to further unravel mechanisms underlying tobacco-enhanced, bacteria-induced disease.

An integrative approach for identification of smoking-related genes involving bladder cancer.

Tobacco smoking is one of the most important environmental risk factors involving bladder tumorigenesis. However, smoking-related genes in bladder carcinogenesis and corresponding genetic effects on bladder cancer risk remain unclear. Weighted correlation network analysis (WGCNA) underlying transcriptome of bladder cancer tissues was applied to identify smoking-related genes. The logistic regression model was utilized to estimate genetic effects of single nucleotide polymorphisms (SNPs) in smoking-related genes on bladder cancer risk in the Chinese and European populations with a total of 6510 cases and 6569 controls, as well as the interaction with smoking status. Transcriptome of cells and tissues was used to profile the expression pattern of candidate genes and their genetic variants. Our results demonstrated that a total of 24 SNPs in 14 smoking-related genes were associated with the risk of bladder cancer, of which rs9348451 in CDKAL1 exhibited an interaction with smoking status (ORinteraction = 1.38, Pinteraction = 1.08 × 10-2) and tobacco smoking might combine with CDKAL1 rs9348451 to increase the risk of bladder cancer (Ptrend = 4.27 × 10-4). Moreover, rs9348451 was associated with CDKAL1 expression in bladder cancer, especially in smokers (P < 0.001). Besides, CDKAL1 was upregulated in bladder cancer compared to normal adjacent tissues, as well as upregulated via treatment of cigarette smoke extracts. This study highlights the important role of nurture and nature, as well as their interaction on tumorigenesis, which provides a new way to decipher the etiology of bladder cancer with smoking status.

Contribution of smoking change to 45-year trend in prevalence of chronic bronchitis in Finland.

AIMS: Tobacco smoking has been identified as the most important risk factor of chronic bronchitis. The aim of this study was to assess the contribution of smoking to the trends in prevalence of chronic bronchitis among men and women in Finland. METHODS: For this purpose, we analysed questionnaires included in national FINRISK and FinHealth studies conducted between 1972 and 2017 in 5-year intervals. A total of 26,475 men and 28,684 women aged 30-59 years were included in the analysis. In addition to smoking, age and socioeconomic status were used as risk factors in the logistic regression model. RESULTS: Smoking in Finland has declined from 51% to 23% in men between 1972 and 2017. In women, it increased from 11% in 1972 to 23% in 2002, with a following decrease to 16% in 2017. The prevalence of chronic bronchitis has generally followed the trend of smoking. The population attributable risk was 60% in men and 49% in women. A decrease in chronic bronchitis was observed in male never-smokers. CONCLUSIONS: Smoking is currently declining in Finland in both men and women. As result, the prevalence of chronic bronchitis is declining and it is approaching baseline independent of smoking. The decrease in never-smokers has yet to be explained.