Health effects associated with smoking: a Burden of Proof study

Understanding the mechanisms of change in social norms around tobacco use: A systematic review and meta-analysis of interventions

BACKGROUND AND AIMS

Tobacco use spreads through social networks influencing social norms around tobacco use. However, the social norms scholarship is extremely diverse and occasionally conflicting, complicating efforts to understand how best to leverage social norms to reduce tobacco use. This study systematically reviewed and meta-analyzed this vast terrain by focusing on social norms measurement and mechanism, and intervention effectiveness and modality aimed at changing social norms around tobacco use and actual tobacco use.

METHODS

We searched Scopus, PubMed, PsycInfo, Clinicaltrials.gov, ProQuest Dissertations, the Cochrane Trial Registry, as well as the websites of the Society for Research on Nicotine and Tobacco, the Open Science Framework, medrXiv and the Truth Initiative for experimental and quasi-experimental evaluation studies of interventions designed to shift tobacco use. We included studies written in English from inception to 30 May 2024. We only included studies which noted social norms or social influence as part of the intervention design or set of measured variables. We excluded studies with only one time point, without an intervention being evaluated and those not published in English. Study screening followed the PRISMA 2020 guidelines, and was conducted by at least two independent reviewers who resolved discrepancies through discussion and consensus. All included studies were analyzed in a narrative synthesis, and those providing sufficient statistics for tobacco and social norms outcomes were included in meta-analyses, which were performed separately for tobacco outcomes and social norms outcomes. Study outcomes were transformed into a standardized mean difference (Hedges' g) and several meta-regressions were fit to explore sources of heterogeneity using a robust variance estimation specification to handle effect size dependency.

RESULTS

A total of 95 studies met inclusion criteria for the narrative synthesis, 200 effect sizes from 86 studies were included in the tobacco outcomes meta-analysis, and 66 effect sizes from 29 studies were included in the social norms outcomes meta-analysis. Nearly 90% of included studies were conducted in high-income settings, with the remainder conducted in middle-income settings. No studies were conducted in Latin America or on the African continent. Social norms change interventions had a statistically significant effect on reducing tobacco use and pro-tobacco social normative perceptions [g = 0.233, 95% confidence interval (CI) = 0.166, 0.301, P < 0.001 and g = 0.292, 95% CI = 0.090, 0.494, P = 0.007, respectively]. Interventions were commonly conducted among schoolchildren in classrooms through multicomponent education sessions, often coupled with regular 'booster' sessions over time. Among adult populations, motivational interviewing and other counselling approaches were used in some cases, and few interventions leveraged digital technologies to change social norms.

CONCLUSIONS

Social norms change interventions appear to be effective for reducing tobacco use and pro-tobacco social normative perceptions. In particular, leveraging role models appears to be the most effective social norms change mechanisms for tobacco control.

Potential roles of cigarette smoking on gut microbiota profile among Chinese men

BACKGROUND

Cigarette smoking is posited as a potential factor in disrupting the balance of the human gut microbiota. However, existing studies with limited sample size have yielded inconclusive results.

METHODS

Here, we assessed the association between cigarette smoking and gut microbial profile among Chinese males from four independent studies (N total = 3308). Both 16S rRNA and shotgun metagenomic sequencing methods were employed, covering 206 genera and 237 species. Microbial diversity and abundance were compared among non-smokers, current smokers, and former smokers.

RESULTS

Actinomyces[g], Atopobium[g], Haemophilus[g], Turicibacter[g], and Lachnospira[g] were found to be associated with smoking status (current smokers vs. non-smokers). Metagenomic data provided a higher resolution at the species level, particularly for the Actinomyces[g] branch. Additionally, serum γ-glutamylcysteine (γ-Glu-Cys) was found to have a potential role in connecting smoking and Actinomyces[g]. Furthermore, we revealed putative mediation roles of the gut microbiome in the associations between smoking and common diseases including cholecystitis and type 2 diabetes.

CONCLUSIONS

We characterized the gut microbiota profile in male smokers and further revealed their potential involvement in mediating the impact of smoking on health outcomes. These findings advance our understanding of the intricate association between cigarette smoking and the gut microbiome.

Association between smoking status and health-related quality of life: a study on differences among age groups

Purpose

This study explored the effect of four different smoking statuses (non-smokers, moderate smokers, heavy smokers, and former smokers) on health-related quality of life (HRQOL) among residents aged 15 years and older in Sichuan Province, China with consideration of potential differences among age groups (young, middle-aged, and older adults).

Methods

The EQ-5D-5L utility index and EQ-VAS score were used to measure HRQOL. Self-reporting and salivary cotinine test were used to determine the smoking status of respondents, and the Tobit regression model was used to explore the relationship between smoking status and HRQOL.

Results

The Tobit regression model found a significant correlation between smoking status and HRQOL. Heavy smokers reported a lower EQ-VAS score compared to non-smokers (p < 0.01); the EQ-5D-5L utility index and EQ-VAS score reported by former smokers were lower compared to non-smokers (p < 0.05 and p < 0.01, respectively). In the young population, the EQ-VAS score of heavy smokers was lower than that of non-smokers (p < 0.05); In the middle-aged population, the EQ-VAS score of heavy smokers was lower than that of non-smokers (p < 0.05). The EQ-5D-5L utility index and EQ-VAS score of former smokers were lower than that of non-smokers (p < 0.05 and p < 0.001, respectively). However, in the older adult population, the EQ-5D-5L utility index and EQ-VAS score of moderate smokers were higher compared to non-smokers (p < 0.05 and p < 0.05, respectively).

Conclusion

This study found a significant correlation between HRQOL and smoking status, with notable differences in the relationship between smoking, EQ-5D-5L utility index, and EQ-VAS scores across age groups. We recommend targeted measures to control tobacco use based on age, considering specific smoking risks for each group. In particular, attention should be paid to the harm of smoking among young and middle-aged groups, reduce the occurrence of smoking behavior through publicity and early intervention, and provide appropriate health interventions for the older adult group. In addition, effective smoking cessation support policies should be developed to encourage residents to quit or reduce smoking frequency, avoid the progression of moderate smoking to heavy smoking and thus lead to serious health threats.

Epilepsy and nicotine use: Exploring disparities in ENDS and cigarette use among US adults with epilepsy

INTRODUCTION

Individuals with epilepsy are at greater risk for tobacco use, which may exacerbate their health challenges. This study examines the prevalence and sociodemographic correlates of electronic nicotine delivery systems (ENDS), cigarette, and dual use among US adults with and without epilepsy.

METHODS

Data from the 2021-2023 National Health Interview Surveys were analyzed (N = 86,655 adults aged ≥ 18 years), including 1,579 (1.89 %, estimated 14.5 million US adults) with self-reported epilepsy (outcome variable). Participants were categorized into mutually exclusive groups: never-use of either product [reference group], current (used on some days or daily) cigarette-only use, ENDS-only, dual-use, former cigarette-only, former ENDS-only, and former dual-use. Weighted logistic regression models assessed the relationship between epilepsy and tobacco use, adjusting for sociodemographic characteristics.

RESULTS

Adults with epilepsy had higher rates of cigarette-only (16.51 % vs. 9.27 %), ENDS-only (5.56 % vs. 3.95 %), and dual use (3.53 % vs. 1.50 %) compared to those without epilepsy. Relative to never use, current cigarette-only use (AOR = 1.66, 95 %CI: 1.36-2.01), current ENDS-only use (AOR = 1.51, 95 %CI: 1.08-2.13), and current dual use (AOR = 2.29, 95 % CI: 1.56-3.48) were associated with higher odds of epilepsy after adjusting for demographic and health factors. Among adults with epilepsy, identifying as gay, lesbian, or bisexual was linked to higher odds of cigarette, ENDS, or dual use compared to straight individuals. Lower levels of education were associated with higher odds of cigarette smoking, while having health insurance was associated with lower odds among adults with epilepsy. Adults ≥ 35 were more likely to smoke cigarettes and less likely to use ENDS compared to younger age groups.

CONCLUSION

Cigarette, ENDS, and dual use rates were higher in adults with epilepsy than in those without epilepsy. Social factors like sexual orientation, education, and insurance status further influence tobacco use within this population. Tailored cessation interventions are warranted for this vulnerable population to reduce disease burden.

Cigarette smoking is associated with reduced neuroinflammation and better cognitive control in people living with HIV

People living with HIV (HIV+) are roughly twice as likely to smoke cigarettes (Smok+) as the general population. With the advent of effective antiretroviral therapies, it is increasingly important to understand the effects of chronic HIV infection and cigarette smoking on brain function and cognition since HIV+ individuals have heightened neuroinflammation and cognitive deficits even with such therapies. Based on prior studies demonstrating that smoking reduces a marker for neuroinflammation in HIV- individuals, we hypothesized that HIV+/Smok+ individuals would have less neuroinflammation and better cognitive control than HIV+/Smok- individuals. Fifty-nine participants (HIV-/Smok- [n = 16], HIV-/Smok+ [n=14], HIV+/Smok- [n = 18], and HIV+/Smok+ [n = 11]) underwent baseline eligibility tests, positron emission tomography (PET) scanning to determine levels of a marker for neuroinflammation, and assessment of cognitive control with the reverse-translated 5-choice continuous performance test (5C-CPT), with smokers having smoked to satiety prior to testing. For the PET data, a significant effect of smoking status on whole brain (WB) standardized uptake value (SUV) was found between HIV+/Smok+ and HIV+/Smok- participants (due to 18.8% lower WB SUV in the HIV+/Smok+ group). HIV+/Smok- participants exhibited a mean 13.5% higher WB SUV than HIV-/Smok- participants. For the 5C-CPT, HIV+/Smok+ participants performed significantly better than HIV+/Smok- participants (d prime), and HIV+/Smok- participants performed worse than HIV-/Smok- participants. Thus, HIV+/Smok+ individuals demonstrated lower levels of the neuroinflammation marker and better cognitive control than HIV+/Smok- individuals. Given that HIV+ individuals whose HIV is well-controlled can still have chronic neurocognitive complications, study results suggest possible paths for future research into nicotine-related treatments to prevent such complications.

Causal Effect of Smoking and Cessation on Tooth Loss

AIM

To estimate the causal effects of smoking and cessation on tooth loss using instrumental variable (IV) analysis.

MATERIAL AND METHODS

Data from the Behavioural Risk Factor Surveillance System (BRFSS), conducted from 1995 to 2006, 2008, 2010, and 2012 in 50 U.S. states and Washington DC, were merged with cigarette pack prices and smoking ban data from the CDC 'Tax Burden on Tobacco' and 'State Tobacco Activities Tracking and Evaluation' (STATE) System. Prices and bans served as IVs for ever smoking and cessation in a control function IV model for self-reported edentulism and loss of 6+ teeth. IV models were adjusted for age, sex, race/ethnicity, educational attainment, type 2 diabetes, state unemployment rates, state health expenditures, and state fixed effects.

RESULTS

Ever smoking cigarettes increased the risk of edentulism by 2.6% (95% CI: 2.3%-2.8%) and the risk of loss of 6+ teeth by 10.7% (95% CI: 10.0%-11.3%). Smoking cessation reduced risks of edentulism and loss of 6+ teeth by 7.6% (95% CI: -7.8% to -742%) and 13.5% (95% CI: -13.7% to 13.3%), respectively.

CONCLUSION

This study provides robust evidence that smoking increases tooth loss risk, while cessation significantly reduces it, emphasizing the oral health benefits of tobacco control policies.

Resuspended Nano-Minerals in Coal Ash: A Potential Factor in Elevated Lung Cancer Rates in Xuanwei and Fuyuan, Yunnan, China

Xuanwei and the neighboring Fuyuan (XF) counties in Yunnan Province have the highest lung cancer incidence rates in China. Previous studies suggest that the nano-minerals released during the combustion of locally sourced "smoky" (bituminous) coal are the primary contributors to these elevated cancer rates. The coal ash generated during combustion predominantly consists of nano-minerals, which can be resuspended into the atmosphere during routine ash-handling activities. In this study, coal ash samples from XF counties and four additional provinces with lower lung cancer incidence rates were resuspended to simulate ash-handling activities and subsequently collected using a cascade PM2.5 sampler. Individual particles were analyzed using a high-resolution scanning electron microscope coupled with energy-dispersive X-ray spectroscopy (SEM-EDX). Based on their morphology and elemental composition, the particles were categorized into five major types: quartz, Si- and Al-rich (SiAl-rich), Ca-rich, Ca- and Mg-rich (CaMg-rich), and Fe-rich particles. The relative abundance of crystalline quartz particles was significantly higher in Xuanwei (22.2%) and Fuyuan (13.7%) compared to the other provinces, where quartz was also detected in lower concentrations. Similarly, the proportion of Fe-rich particles was notably higher in Xuanwei (10.9%) and Fuyuan (5.1%) than in other regions. These findings highlight the potential role of quartz and Fe-rich particles in contributing to the high lung cancer rates observed in XF counties. Further research is warranted to elucidate the toxicological mechanisms underlying the health effects of these particle types.

Current Status and Future Perspective of Onco-Hypertension

BACKGROUND

Hypertension and cancer are both increasing with age. Recently, the new concept of "Onco-Hypertension" has been proposed to address the mutual risks posed by hypertension and cancer and to provide comprehensive care for patients with these two conditions in an aging society.

METHODS

In this review, we provide an overview of the current status and future perspective of the "Onco-Hypertension," including our research findings.

RESULTS

Hypertension and cancer share common risk factors and may be interrelated in pathogenesis: Hypertension is involved in the development of certain cancers, and cancer survivors have a higher incidence of hypertension. With recent advances in cancer therapy, the number of cancer survivors has increased. Cancer survivors not only have a higher risk of incident hypertension but also an increased risk of future cardiovascular events, highlighting the growing importance of comprehensive care.

CONCLUSIONS

There exists a diverse array of epidemiological and pathophysiological relationships between hypertension and cancer. It is imperative to move the emerging scientific field of "Onco-Hypertension" forward through relentless research efforts.

Incident Cardiometabolic Comorbidities in Smokers with/Without Chronic Obstructive Pulmonary Disease: A Long-Term Cohort Study

Backgrounds: Despite the significant global health impact of cardiometabolic multimorbidity (CMM), our understanding of potential predictors associated with its development in smokers, remains limited. Objective: This study aimed to investigate whether a new COPD diagnosis and the rate of lung function decline serve as predictors for incident CMM (defined as having at least two of the following comorbidities: cerebro-cardiovascular diseases, hypertension, dyslipidemia, and diabetes mellitus) in smokers. Methods: An observational longitudinal analysis of prospectively collected data was conducted, including smokers without a previous COPD diagnosis and any cardiometabolic conditions. Sociodemographic and clinical data (body mass index, smoking history, respiratory symptoms, and hospital admissions) were collected at baseline. Lung function tests were performed at baseline and at the end of the follow-up period. The incidence of CMM, a new positive diagnosis of COPD, and the forced expiratory volume in 1 s (FEV1) annual rate of decline were prospectively registered. Adjusted Cox proportional hazard models were adopted to explore risk factors associated with the incidence of CMM. Results: From the 391 smokers included in the study, 207 (53%) were newly diagnosed with COPD, and 184 had a preserved spirometry at baseline (non-COPD group). After nearly a decade of follow-up, 34% (n = 133) of smokers developed CMM. This group was characterized by male predominance, older age, higher BMI and pack-years of smoking, lower post-FEV1, baseline COPD diagnosis, and a history of hospital admission. A positive diagnosis of COPD at baseline and a greater rate of lung function decline (ΔFEV1 ≥ 40 mL/year) were independent predictors for developing CMM. Conclusions: A new COPD diagnosis and an accelerated decline in lung function are significantly associated with the development of CMM in smokers.

Return on investment of tobacco control measures: a systematic review protocol

OBJECTIVE

The objective of this systematic review will be to estimate the return on investment (ROI) and social return on investment (SROI) on tobacco control measures.

INTRODUCTION

Tobacco consumption has been proven to be associated with a huge epidemiological, humanistic, and economic burden. National and international organizations are making concerted efforts to control tobacco use. However, currently, there are no conclusive estimates of the ROI and SROI of such programs and policies.

INCLUSION CRITERIA

This review will include all studies that evaluate the ROI or SROI on tobacco control programs and policies on tobacco users and probable tobacco users globally.

METHODS

This review will follow the JBI methodology for systematic reviews of economic evidence. Databases to be searched will include Embase (Ovid), MEDLINE (PubMed), Cochrane Central Register of Controlled Trials (CENTRAL), Health Economic Evaluation Database (HEED), National Health Service Economic Evaluation Database (NHS EED), CEA Registry, LILACS, Science Direct, Web of Science, EconLit, and Google Advanced Search. Gray literature will also be searched for in non-academic databases, including the websites of various civil societies and non-governmental organizations involved in tobacco control. Two independent reviewers will screen titles/abstracts, and later full-text studies. Critical appraisal will be conducted using the JBI checklist for economic evaluations and the SROI Quality Framework. Data will be extracted and synthesized using JBI data extraction forms and synthesis tools. The MPOWER framework will be considered for data synthesis across all selected studies using narrative synthesis, tables, and figures.

REVIEW REGISTRATION

PROSPERO CRD42023391591.

Smokers' Characteristics Associated with Successful Smoking Cessation Undergoing Pharmacotherapy in Slovenia

Introduction

Tobacco use is a major global health problem, contributing to premature death and disability. In Slovenia, the prevalence of smoking is higher than the EU average, emphasizing the need for effective tobacco control measures. The aim of this study was to identify the characteristics of patients most likely to benefit from pharmacotherapy for smoking cessation.

Methods

We performed cross-sectional analysis of factors associated with successful smoking cessation using pharmacotherapy for Slovenian smokers. A total of 176 (24.6%) smokers with an average age of 50 years agreed to receive pharmacotherapy for their smoking cessation attempt and were enrolled in the study. Participants were followed up at 4-week intervals during treatment and for 24 weeks after completion of pharmacotherapy.

Results

Attempts to quit smoking with prescription medications were successful in 24.4% of those willing to try. Female smokers, older persons, those with more children, with a lower self-perception of health, a higher number of cigarettes per day and a higher nicotine dependence were more likely to attempt to quit smoking. However, the strongest predictors of smoking cessation success were lower nicotine dependence, which was tested using the Fagerström test for nicotine dependence, and higher adherence to pharmacotherapy.

Conclusion

Nicotine dependence and adherence to pharmacotherapy are the strongest predictors of a successful smoking cessation attempt. Identification of potential responders, prescription of pharmacotherapy and follow-up are applicable in the primary healthcare setting.

Characterization of the nicotine uptake and safety of Nordic spirit tobacco-free oral nicotine pouches: A randomized cross-over study

RATIONALE

Given the nascency of tobacco-free oral nicotine pouches (NPs) and the heterogeneity of commercially available NP brands, there is a need for scientific evaluation of different NP formulations. Nordic Spirit, novel NPs are distinguished by their unique composition.

OBJECTIVES

To characterize blood nicotine delivery, pharmacokinetics (PK), subjective and physiological effects and to monitor safety of three Nordic Spirit NPs (6 mg, 9 mg and 11.2 mg/pouch) compared with LD tobacco snus (11.2 mg/pouch) and Nicorette® gum (4 mg/unit) following single 30 min use.

METHODS

This was a randomized, open-label, ten-sequence, single-use, cross-over clinical study with 30 healthy adult Swedish snus users.

RESULTS

Peak nicotine concentrations (Cmax) ranged from 10.92 to 17.32 ng/mL for the three Nordic Spirit NPs, with a trend toward dose proportionality, and 8.18 ng/mL and 9.23 ng/mL for the LD snus and Nicorette® gum comparators, respectively. Peak concentration for Nordic Spirit NPs was reached (Tmax) after 30 to 38 min, and after 45 min for LD snus and Nicorette® gum. No notable safety concerns were observed after single use for any of the study products.

CONCLUSIONS

Delivery of nicotine from the three Nordic Spirit NPs appeared to be nicotine content-dependent, based on Cmax and AUC. The amount of nicotine extracted showed positive correlation with the reported Cmax and AUC. For Nordic Spirit NPs, Tmax was immediately after end of use. The characteristics of Nordic Spirit NPs were found to be favourable for profiling NP nicotine delivery and safety in human use, and for further product development. ISRCTN registry study no. ISRCTN75583947.

Socioeconomic Variation in Tobacco Smoking Among the Adult Population in Ireland

INTRODUCTION

Differences in smoking prevalence across socioeconomic groups are a major driver of health inequalities. Although smoking prevalence continues to decline across most developed countries, socioeconomic inequalities in smoking still persist. While Ireland is among a small number of countries with a tobacco-endgame goal set to achieve a smoking prevalence of 5% by 2025, the challenge this presents by socioeconomic status is uncharted.

AIMS AND METHODS

We analyzed how differences in smoking status across various socioeconomic groups have changed over time in the adult population in Ireland. We used cross-sectional smoking data from the national population-based Healthy Ireland Survey for 2015-2022 (n = 52 494). Educational attainment and area-based deprivation were used as socioeconomic indicators. Socioeconomic differences and changes in inequality over time were identified using the relative index of inequality (RII). Multinomial logistic regression was used to analyze the association between socioeconomic status and daily smoking, occasional smoking, former smoking, and never smoking with adjustment for sex, age, and survey year.

RESULTS

We observed the highest daily smoking rates among the least educated (OR = 11.62; 95% CI = 9.91, 13.63) and individuals living in the most deprived areas (OR = 4.23; 95% CI = 3.55, 5.04). Additionally, we identified significant relative smoking inequalities over the observation period continued to increase, among the least educated (RII = 2.86, 95%CI = 2.63, 3.09) and individuals living in the most deprived areas (RII = 2.64, 95% CI = 2.36, 2.93).

CONCLUSIONS

Despite generally reducing smoking prevalence, socioeconomic inequalities continue to widen among the smoking population in Ireland.

IMPLICATIONS

As the tobacco endgame deadline of 2025 is fast approaching, this study highlights the urgent need to consider potential effects across the lowest socioeconomic status groups when implementing equity-oriented tobacco control policies.

Interactive association of metals and Life's Essential 8 with mortality in U.S. adults: a prospective cohort study from the NHANES dataset

BACKGROUND

Life's Essential 8 (LE8) is a novel assessment of cardiovascular health (CVH) by evaluating lifestyle, and reports of the associations between LE8 and urinary metals on mortality have been very limited. This study aimed to conduct a prospective cohort study and investigate the combined effects of metals and LE8 on mortality in U.S. adults.

METHODS

This study enrolled participants with complete information on urinary metals, LE8, mortality status, and confounders from the National Health and Nutrition Examination Survey (2005-2018). The Cox regression model, adaptive lasso penalized regression, and restricted cubic spline were used to analyze the individual effects of metals and LE8 on all-cause mortality. The additive and multiplicative interaction scales and quantile g-computation were used to evaluate the interaction and combined effects. Stratified analyses were performed to clarify whether metals and LE8 interacted with other variables to influence all-cause mortality.

RESULTS

A total of 8017 participants were included in this study. The concentrations of cadmium, cobalt, lead, antimony, and thorium were greater in the low CVH group than in the high CVH group [median (µg/L): 0.29 vs. 0.19, 0.36 vs. 0.35, 0.48 vs. 0.39, 0.05 vs. 0.04, and 0.07 vs. 0.06]. The interaction between cadmium and LE8 was statistically significant, with a synergy index of 1.169 (95% CI: 1.004, 1.361). The stratified analyses showed that the interaction between age and LE8 had an impact on all-cause mortality (P for interaction = 0.004).

CONCLUSIONS

In this representative sample of the U.S. population, we found that the combined effect of cadmium, lead, thallium, and LE8 was positively associated with all-cause mortality. Furthermore, the interaction between cadmium and LE8 influenced all-cause mortality. So people should adopt healthy behaviors and reduce heavy metal exposure to minimize the risk of adverse health outcomes.

The causal nexus between diverse smoking statuses, potential therapeutic targets, and NSCLC: insights from Mendelian randomization and mediation analysis

Objective

Lung cancer, the most prevalent malignancy, is typically diagnosed at an advanced stage. Smoking is a pivotal risk factor for NSCLC, yet the impact of various smoking statuses on NSCLC remains unclear. Thus, this study aims to explore whether different smoking statuses can causally influence NSCLC through effects on predictive targets, offering a novel perspective for NSCLC treatment.

Methods

Employing dual-sample MR, MVMR, and TSMR approaches, we assessed the causal relationships between 13 distinct smoking statuses and NSCLC, using predicted potential therapeutic targets as mediators to further elucidate the causal interplay among them.

Results

Among the 13 smoking statuses, current tobacco smoking, exposure to tobacco smoke outside the home, past tobacco smoking, and never smoked demonstrated causal relationships with NSCLC. MVMR analysis reveals that Current tobacco smoking is an independent risk factor for NSCLC. Utilizing NCAPD2, IL11RA, and MLC1 as mediators, IL11RA (22.2%) was found to potentially mediate the relationship between past tobacco smoking and NSCLC.

Conclusion

This study, integrating bioinformatics and MR analysis, identified three potential predictive targets as mediators to investigate the causal relationships between different smoking statuses and NSCLC through potential therapeutic targets, providing new insights for the treatment and prevention of NSCLC.

A multi-ancestry cerebral cortex transcriptome-wide association study identifies genes associated with smoking behaviors

Transcriptome-wide association studies (TWAS) have provided valuable insight in identifying genes that may impact cigarette smoking. Most of previous studies, however, mainly focused on European ancestry. Limited TWAS studies have been conducted across multiple ancestries to explore genes that may impact smoking behaviors. In this study, we used cis-eQTL data of cerebral cortex from multiple ancestries in MetaBrain, including European, East Asian, and African samples, as reference panels to perform multi-ancestry TWAS analyses on ancestry-matched GWASs of four smoking behaviors including smoking initiation, smoking cessation, age of smoking initiation, and number of cigarettes per day in GWAS & Sequencing Consortium of Alcohol and Nicotine use (GSCAN). Multiple-ancestry fine-mapping approach was conducted to identify credible gene sets associated with these four traits. Enrichment and module network analyses were further performed to explore the potential roles of these identified gene sets. A total of 719 unique genes were identified to be associated with at least one of the four smoking traits across ancestries. Among those, 249 genes were further prioritized as putative causal genes in multiple ancestry-based fine-mapping approach. Several well-known smoking-related genes, including PSMA4, IREB2, and CHRNA3, showed high confidence across ancestries. Some novel genes, e.g., TSPAN3 and ANK2, were also identified in the credible sets. The enrichment analysis identified a series of critical pathways related to smoking such as synaptic transmission and glutamate receptor activity. Leveraging the power of the latest multi-ancestry GWAS and eQTL data sources, this study revealed hundreds of genes and relevant biological processes related to smoking behaviors. These findings provide new insights for future functional studies on smoking behaviors.

Causal impacts of smoking on pain conditions and the mediating pathways: a mendelian randomization study

Smoking is a risk factor for multiple diseases. We performed mendelian randomization (MR) analyses to investigate the causal association of smoking initiation on pain conditions and the potential mediating pathways. Genetic associated with smoking initiation at the genome-wide significance level were selected as instrumental variables. Genetic associations with 10 pain conditions were derived from the FinnGen and UK Biobank study. Multivariable MR analysis was conducted to explore the mediation effects of depression, insomnia and sedentary behavior. A series of sensitivity analyses were conducted to assess the stability of our research findings. Genetic liability to smoking initiation was associated with an increased risk of angina pectoris, dorsalgia, low back pain, pain in limb, pain in joint, pain in thoracic spine and sciatica in both FinnGen and UK Biobank study. These causal associations were largely mediated by major depression (2.9- 39.5%), sedentary behavior (13.0- 31.2%), insomnia (10.3- 33.1%) and combination of all three mediators (30.2- 65.3%). The effects of smoking on outcomes were partly attenuated after adjusting for depression, sedentary behavior and insomnia respectively, and the direct effect of smoking initiation on pain was diminished toward null after adjusting for combined three mediators. These results were robust to sensitivity analyses. Our findings illustrated the causal effect of smoking and a broad range of pain conditions, and major depression, sedentary behavior and insomnia mediate many of these associations.

Effects of passive smoking on cortical spreading depolarization in male and female mice

BACKGROUND

Patients with migraine are typically advised to avoid passive smoking because it may aggravate headaches and other health conditions. However, there is insufficient high-quality evidence on the association between passive smoking and migraine, which warrants further investigation using animal models. Therefore, using a mouse model, we examined the effect of passive smoking on susceptibility to cortical spreading depolarization (CSD), the biological basis of migraine with aura.

FINDINGS

Fifty C57BL/6 mice (25 males and 25 females) were exposed for one hour to cigarette smoke or room air. Subsequently, potassium chloride (KCl) was administered under isoflurane anesthesia to induce CSD, and the CSD threshold, frequency of induction, and propagation velocity were determined. The threshold to induce CSD (median [interquartile range (IQR)]) was significantly lower in female mice (adjusted p = 0.01) in the smoking group (0.05 [0.05, 0.088]) than in the sham group (0.125 [0.1, 0.15]); however, there was no significant difference in the male mice (adjusted p = 0.77). CSD frequency or propagation velocity did not differ significantly between the two groups for either sex.

CONCLUSIONS

Female mice in the smoking group showed lower CSD threshold compared to the sham group, suggesting a potential sex-specific difference in the effect of smoking on the pathogenesis of CSD and migraine with aura. This finding may contribute to the understanding of migraine pathophysiology in association with passive smoking and sex difference.

Probabilistic inference of epigenetic age acceleration from cellular dynamics

The emergence of epigenetic predictors was a pivotal moment in geroscience, propelling the measurement and concept of biological aging into a quantitative era; however, while current epigenetic clocks show strong predictive power, they are data-driven in nature and are not based on the underlying biological mechanisms driving methylation dynamics. We show that predictions of these clocks are susceptible to several confounding non-age-related phenomena that make interpretation of these estimates and associations difficult. To address these limitations, we developed a probabilistic model describing methylation transitions at the cellular level. Our approach reveals two measurable components, acceleration and bias, which directly reflect perturbations of the underlying cellular dynamics. Acceleration is the proportional increase in the speed of methylation transitions across CpG sites, whereas bias corresponds to global changes in methylation levels. Using data from 15,900 participants from the Generation Scotland study, we develop a robust inference framework and show that these are two distinct processes confounding current epigenetic predictors. Our results show improved associations of acceleration and bias with physiological traits known to impact healthy aging, such as smoking and alcohol consumption, respectively. Furthermore, a genome-wide association study of epigenetic age acceleration identified seven genomic loci.

Effect of family history of cancer on postoperative survival in patients with non-small cell lung cancer

Background

Family history of cancer (FHC) has been reported to increase mortality of non-small cell lung cancer, mainly comprised of lung adenocarcinoma (LUAD) and lung squamous cell carcinoma (LUSC). However, the impact of FHC on long-term survival remains controversial. This study aims to identify the impact of FHC on postoperative survival in LUAD and LUSC.

Methods

Patients underwent lung resection for LUAD or LUSC in West China Hospital from 2009 to 2021 were enrolled. The 5-year overall survival (OS), lung cancer-specific survival (LCSS) and progression-free survival (PFS) were compared between the patients with and without FHC. Multivariable Cox regression was also performed.

Results

A total of 6,253 patients were enrolled, including 5,685 LUAD and 568 LUSC. Altogether 18.9% (1,077/5,685) patients had FHC in LUAD, and 12.7% (72/568) patients had FHC in LUSC. In LUAD, the patients with FHC showed comparable survival compared with the patients without FHC regarding 5-year OS (87.9% vs. 86.5%, P=0.49), 5-year PFS (84.8% vs. 80.9%, P=0.06), and 5-year LCSS (89.2% vs. 88.0%, P=0.96). In LUSC, the patients with FHC had poorer survival compared with the patients without FHC according to 5-year OS (40.9% vs. 68.2%, P=0.007), 5-year PFS (42.3% vs. 66.2%, P=0.003), and 5-year LCSS (45.8% vs. 72.7%, P=0.003). Multivariate analyses indicated that FHC was an independent prognostic factor of OS, PFS, and LCSS in the patients with LUSC.

Conclusions

FHC was associated with a poor survival after lung resection in LUSC not LUAD patients. More attention should be paid in postoperative monitoring and treatment in LUSC patients with FHC.

Occupational injuries and their sociodemographic, workplace, and behavioral determinants among large-scale factory workers in Ethiopia: a cross-sectional study

Workplace injuries constitute a serious and growing public health concern worldwide. Despite work-related injuries being highly common, especially among workers in the manufacturing industry, their growing complexities are not adequately addressed in the current literature. Therefore this study aims to investigate the association between sociodemographic, workplace, and behavioral characteristics with work-related injuries among large-scale factory workers in Ethiopia. A cross-sectional study was conducted from February to April 2020 with 457 workers selected from large-scale factories in Addis Ababa, the capital of Ethiopia. Survey data included sociodemographic characteristics, working and safety conditions, and behavioral factors as predictors of occupational injuries. A logistic regression model was fitted to estimate the probability of injury and identify its associated factors. The 12-month prevalence of work-related injuries was 25%. Most injuries occurred at midnight (8.8%). Factors associated with work-related injury were excessive working hours (OR = 3.26; 95%CI: 1.26-8.41), cigarette smoking (OR = 2.72; 95%CI: 1.22-6.08), and manual handling (OR = 2.30; 95%CI: 1.13-4.72). Use of personal protective equipment reduced the odds of injury (OR = 0.42; 95%CI: 0.21-0.83). Although our estimated prevalence of occupational injury was lower than that found in other studies, our findings suggest that actions on modifiable conditions must be taken to reduce the burden of workplace injuries in Ethiopia. The results could inform preparedness and policy efforts aimed at improving worker safety and health.

An epigenetic memory at the CYP1A gene in cancer-resistant, pollution-adapted killifish

Human exposure to polycyclic aromatic hydrocarbons (PAH) is a significant and growing public health problem. Frequent, high dose exposures are likely to increase due to a warming climate and increased frequency of large-scale wildfires. Here, we characterize an epigenetic memory at the cytochrome P450 1A (CYP1A) gene in a population of wild Fundulus heteroclitus that has adapted to chronic, extreme PAH pollution. In wild-type fish, CYP1A is highly induced by PAH. In PAH-tolerant fish, CYP1A induction is blunted. Since CYP1A metabolically activates PAH, this memory protects these fish from PAH-mediated cancer. However, PAH-tolerant fish reared in clean water recover CYP1A inducibility, indicating that blunted induction is a non-genetic memory of prior exposure. To explore this possibility, we bred depurated wild fish from PAH-sensitive and - tolerant populations, manually fertilized exposure-naïve embryos, and challenged them with PAH. We observed epigenetic control of the reversible memory of generational PAH stress in F1 PAH-tolerant embryos. Specifically, we observed a bivalent domain in the CYP1A promoter enhancer comprising both activating and repressive histone post-translational modifications. Activating modifications, relative to repressive ones, showed greater increases in response to PAH in sensitive embryos, relative to tolerant, consistent with greater gene activation. Also, PAH-tolerant adult fish showed persistent induction of CYP1A long after exposure cessation, which is consistent with defective CYP1A shutoff and recovery to baseline. Since CYP1A expression is inversely correlated with cancer risk, these results indicate that PAH-tolerant fish have epigenetic protection against PAH-induced cancer in early life that degrades in response to continuous gene activation.

Association of conventional cigarette smoking, heated tobacco product use and dual use with hypertension

BACKGROUND

Heated tobacco products (HTPs) have emerged as alternatives to conventional cigarettes. However, their health effects remain largely unknown. This study aimed to prospectively explore the association between the use of cigarettes and HTPs and the risk of hypertension.

METHODS

This cohort study analysed data from 30 152 workers (82.0% men, mean age 42.9 ± 11.0 years) who were initially free of hypertension, participating in the Japan Epidemiology Collaboration on Occupational Health Study. Participants were categorized into five groups based on their self-reported tobacco product use: never smokers, past smokers, exclusive cigarette smokers, exclusive HTP users and dual users of cigarettes and HTPs. Hypertension cases were identified using three data points from annual health checkup data collected between 2019 and 2021. Cox proportional hazards regression models were used to investigate the association between tobacco product use and hypertension.

RESULTS

During a mean follow-up of 2.6 years (range: 0.1-4.0 years), 3656 new cases of hypertension were identified. Compared with never smokers, the risk of hypertension was higher among exclusive cigarette smokers [hazard ratio (HR) 1.26, 95% confidence interval (CI) 1.13-1.41] and exclusive HTP users (HR 1.19, 95% CI 1.06-1.34). There was also a suggestion of increased risk of hypertension among dual users (HR 1.16, 95% CI 0.98-1.38). Furthermore, the risk of hypertension increased with the intensity of cigarette/HTP use in all tobacco product users.

CONCLUSIONS

Similarly, both cigarette smoking and HTP use elevate the risk of hypertension. HTPs should not be regarded as less harmful alternatives to traditional cigarettes for preventing hypertension.

Western diets and chronic diseases

'Westernization', which incorporates industrial, cultural and dietary trends, has paralleled the rise of noncommunicable diseases across the globe. Today, the Western-style diet emerges as a key stimulus for gut microbial vulnerability, chronic inflammation and chronic diseases, affecting mainly the cardiovascular system, systemic metabolism and the gut. Here we review the diet of modern times and evaluate the threat it poses for human health by summarizing recent epidemiological, translational and clinical studies. We discuss the links between diet and disease in the context of obesity and type 2 diabetes, cardiovascular diseases, gut and liver diseases and solid malignancies. We collectively interpret the evidence and its limitations and discuss future challenges and strategies to overcome these. We argue that healthcare professionals and societies must react today to the detrimental effects of the Western diet to bring about sustainable change and improved outcomes in the future.

Effectiveness of a Digital Health Game Intervention on Early Adolescent Smoking Refusal Self-Efficacy

Smoking poses a significant threat to adolescent health because of its immediate and long-term detrimental health effects. Smoking refusal self-efficacy predicts smoking behavior in adolescence. In adolescents' health education, digital interventions are potential tools to support smoking refusal self-efficacy. The aim of this two-arm cluster randomized controlled trial was to evaluate the effectiveness of a digital health game intervention compared with a no-intervention control group on smoking refusal self-efficacy in 10- to 13-year-old Finnish early adolescents. The early adolescents (n = 781) were randomized to the control group (n = 394) and the health game intervention group (n = 387). Smoking refusal self-efficacy, sources of smoking and snus refusal self-efficacy, and motivation to decline smoking and snus use in the future were measured at baseline, 2-week postintervention, and 3-month follow-up. Data were analyzed using linear mixed model and Wilcoxon rank-based test for clustered data. According to the results, the intervention group made improvements in sources of smoking and snus refusal self-efficacy between baseline and postintervention, and in sources of snus refusal self-efficacy between baseline and follow-up, compared with the control group. The intervention group showed improvements in smoking refusal self-efficacy among 12-year-olds between baseline and follow-up, and postintervention and follow-up compared with the control group. Similar improvements were also found among those with a smoking friend or a smoking parent between postintervention and follow-up. The results were promising for the use of digital health game interventions to promote early adolescent smoking refusal self-efficacy and preventing smoking experimentation. Further research can evaluate the long-term effects for adolescents.

Systematic Review of Naturally Derived Substances That Act as Inhibitors of the Nicotine Metabolizing Enzyme Cytochrome P450 2A6

Tobacco smoking has been highlighted as a major health challenge in modern societies. Despite not causing death directly, smoking has been associated with several health issues, such as cardiovascular diseases, respiratory disorders, and several cancer types. Moreover, exposure to nicotine during pregnancy has been associated with adverse neurological disorders in babies. Nicotine Replacement Therapy (NRT) is the most common strategy employed for smoking cessation, but despite its widespread use, NRT presents with low success and adherence rates. This is attributed partially to the rate of nicotine metabolism by cytochrome P450 2A6 (CYP2A6) in each individual. Nicotine addiction is correlated with the high rate of its metabolism, and thus, novel strategies need to be implemented in NRT protocols. Naturally derived products are a cost-efficient and rich source for potential inhibitors, with the main advantages being their abundance and ease of isolation. This systematic review aims to summarize the natural products that have been identified as CYP2A6 inhibitors, validated through in vitro and/or in vivo assays, and could be implemented as nicotine metabolism inhibitors. The scope is to present the different compounds and highlight their possible implementation in NRT strategies. Additionally, this information would provide valuable insight regarding CYP2A6 inhibitors, that can be utilized in drug development via the use of in silico methodologies and machine-learning models to identify new potential lead compounds for optimization and implementation in NRT regimes.

Association of cigarette smoking, smoking cessation with the risk of cardiometabolic multimorbidity in the UK Biobank

BACKGROUND

To investigate the association between cigarette smoking, smoking cessation and the trajectory of cardiometabolic multimorbidity (CMM), and further to examine the association of age at smoking initiation and smoking cessation with CMM.

METHODS

This study included 298,984 UK Biobank participants without cardiometabolic diseases (CMDs) (including type 2 diabetes, coronary heart diseases, stroke, and hypertension) at baseline. Smoking status was categorized into former, current, and never smokers, with age at smoking initiation and smoking cessation as a proxy for current and former smokers. The multi-state model was performed to evaluate the association between cigarette smoking, smoking cessation and CMM.

RESULTS

During a median follow-up of 13.2 years, 59,193 participants developed first cardiometabolic disease (FCMD), 14,090 further developed CMM, and 16,487 died. Compared to former smokers, current smokers had higher risk at all transitions, with hazard ratio (95% confidence interval) = 1.59 (1.55 ∼ 1.63) vs. 1.18 (1.16 ∼ 1.21) (P = 1.48 × 10- 118) from health to FCMD, 1.40 (1.33 ∼ 1.47) vs. 1.09 (1.05 ∼ 1.14) (P = 1.50 × 10- 18) from FCMD to CMM, and 2.87 (2.72 ∼ 3.03) vs. 1.38 (1.32 ∼ 1.45) (P < 0.001) from health, 2.16 (1.98 ∼ 2.35) vs. 1.25 (1.16 ∼ 1.34) (P = 1.18 × 10- 46) from FCMD, 2.02 (1.79 ∼ 2.28) vs. 1.22 (1.09 ∼ 1.35) (P = 3.93 × 10- 17) from CMM to death; whereas quitting smoking reduced the risk attributed to cigarette smoking by approximately 76.5% across all transitions. Reduced risks of smoking cessation were also identified when age at quitting smoking was used as a proxy for former smokers.

CONCLUSIONS

Cigarette smoking was associated with a higher risk of CMM across all transitions; however, smoking cessation, especially before the age of 35, was associated with a significant decrease in CMM risk attributed to cigarette smoking.

Global, regional, and national age-specific progress towards the 2020 milestones of the WHO End TB Strategy: a systematic analysis for the Global Burden of Disease Study 2021

BACKGROUND

Global evaluations of the progress towards the WHO End TB Strategy 2020 interim milestones on mortality (35% reduction) and incidence (20% reduction) have not been age specific. We aimed to assess global, regional, and national-level burdens of and trends in tuberculosis and its risk factors across five separate age groups, from 1990 to 2021, and to report on age-specific progress between 2015 and 2020.

METHODS

We used the Global Burden of Diseases, Injuries, and Risk Factors Study 2021 (GBD 2021) analytical framework to compute age-specific tuberculosis mortality and incidence estimates for 204 countries and territories (1990-2021 inclusive). We quantified tuberculosis mortality among individuals without HIV co-infection using 22 603 site-years of vital registration data, 1718 site-years of verbal autopsy data, 825 site-years of sample-based vital registration data, 680 site-years of mortality surveillance data, and 9 site-years of minimally invasive tissue sample (MITS) diagnoses data as inputs into the Cause of Death Ensemble modelling platform. Age-specific HIV and tuberculosis deaths were established with a population attributable fraction approach. We analysed all available population-based data sources, including prevalence surveys, annual case notifications, tuberculin surveys, and tuberculosis mortality, in DisMod-MR 2.1 to produce internally consistent age-specific estimates of tuberculosis incidence, prevalence, and mortality. We also estimated age-specific tuberculosis mortality without HIV co-infection that is attributable to the independent and combined effects of three risk factors (smoking, alcohol use, and diabetes). As a secondary analysis, we examined the potential impact of the COVID-19 pandemic on tuberculosis mortality without HIV co-infection by comparing expected tuberculosis deaths, modelled with trends in tuberculosis deaths from 2015 to 2019 in vital registration data, with observed tuberculosis deaths in 2020 and 2021 for countries with available cause-specific mortality data.

FINDINGS

We estimated 9·40 million (95% uncertainty interval [UI] 8·36 to 10·5) tuberculosis incident cases and 1·35 million (1·23 to 1·52) deaths due to tuberculosis in 2021. At the global level, the all-age tuberculosis incidence rate declined by 6·26% (5·27 to 7·25) between 2015 and 2020 (the WHO End TB strategy evaluation period). 15 of 204 countries achieved a 20% decrease in all-age tuberculosis incidence between 2015 and 2020, eight of which were in western sub-Saharan Africa. When stratified by age, global tuberculosis incidence rates decreased by 16·5% (14·8 to 18·4) in children younger than 5 years, 16·2% (14·2 to 17·9) in those aged 5-14 years, 6·29% (5·05 to 7·70) in those aged 15-49 years, 5·72% (4·02 to 7·39) in those aged 50-69 years, and 8·48% (6·74 to 10·4) in those aged 70 years and older, from 2015 to 2020. Global tuberculosis deaths decreased by 11·9% (5·77 to 17·0) from 2015 to 2020. 17 countries attained a 35% reduction in deaths due to tuberculosis between 2015 and 2020, most of which were in eastern Europe (six countries) and central Europe (four countries). There was variable progress by age: a 35·3% (26·7 to 41·7) decrease in tuberculosis deaths in children younger than 5 years, a 29·5% (25·5 to 34·1) decrease in those aged 5-14 years, a 15·2% (10·0 to 20·2) decrease in those aged 15-49 years, a 7·97% (0·472 to 14·1) decrease in those aged 50-69 years, and a 3·29% (-5·56 to 9·07) decrease in those aged 70 years and older. Removing the combined effects of the three attributable risk factors would have reduced the number of all-age tuberculosis deaths from 1·39 million (1·28 to 1·54) to 1·00 million (0·703 to 1·23) in 2020, representing a 36·5% (21·5 to 54·8) reduction in tuberculosis deaths compared to those observed in 2015. 41 countries were included in our analysis of the impact of the COVID-19 pandemic on tuberculosis deaths without HIV co-infection in 2020, and 20 countries were included in the analysis for 2021. In 2020, 50 900 (95% CI 49 700 to 52 400) deaths were expected across all ages, compared to an observed 45 500 deaths, corresponding to 5340 (4070 to 6920) fewer deaths; in 2021, 39 600 (38 300 to 41 100) deaths were expected across all ages compared to an observed 39 000 deaths, corresponding to 657 (-713 to 2180) fewer deaths.

INTERPRETATION

Despite accelerated progress in reducing the global burden of tuberculosis in the past decade, the world did not attain the first interim milestones of the WHO End TB Strategy in 2020. The pace of decline has been unequal with respect to age, with older adults (ie, those aged >50 years) having the slowest progress. As countries refine their national tuberculosis programmes and recalibrate for achieving the 2035 targets, they could consider learning from the strategies of countries that achieved the 2020 milestones, as well as consider targeted interventions to improve outcomes in older age groups.

FUNDING

Bill & Melinda Gates Foundation.

Comparison of smoking traditional, heat not burn and electronic cigarettes on salivary cytokine, chemokine and growth factor profile in healthy young adults-pilot study

Objective: Smoking is the cause of numerous oral pathologies. The aim of the study was to evaluate the effect of smoking traditional cigarettes, e-cigarettes, and heat-not-burn products on the content of salivary cytokines, chemokines, and growth factors in healthy young adults. Design: Three groups of twenty-five smokers each as well as a control group matched in terms of age, gender, and oral status were enrolled in the study. In unstimulated saliva collected from study groups and participants from the control group, the concentrations of cytokines, chemokines, and growth factors were assessed by Bio-Plex® Multiplex System. Results: We demonstrated that smoking traditional cigarettes is responsible for increasing the level of IFN-γ compared to non-smokers and new smoking devices users in unstimulated saliva in the initial period of addiction. Furthermore, e-cigarettes and heat-not-burn products appear to have a similar mechanism of affecting the immune response system of unstimulated saliva, leading to inhibition of the local inflammatory response in the oral cavity. Conclusion: Smoking traditional cigarettes as well as e-cigarettes and heat-not-burn products is responsible for changes of the local immune response in saliva. Further research is necessary to fill the gap in knowledge on the effect of new smoking devices on the oral cavity immune system.

Metabolic profiling of smoking, associations with type 2 diabetes and interaction with genetic susceptibility

BACKGROUND

Smokers are at increased risk of type 2 diabetes (T2D), but the underlying mechanisms are unclear. We investigated if the smoking-T2D association is mediated by alterations in the metabolome and assessed potential interaction with genetic susceptibility to diabetes or insulin resistance.

METHODS

In UK Biobank (n = 93,722), cross-sectional analyses identified 208 metabolites associated with smoking, of which 131 were confirmed in Mendelian Randomization analyses, including glycoprotein acetyls, fatty acids, and lipids. Elastic net regression was applied to create a smoking-related metabolic signature. We estimated hazard ratios (HR) of incident T2D in relation to baseline smoking/metabolic signature and calculated the proportion of the smoking-T2D association mediated by the signature. Additive interaction between the signature and genetic risk scores for T2D (GRS-T2D) and insulin resistance (GRS-IR) on incidence of T2D was assessed as relative excess risk due to interaction (RERI).

FINDINGS

The HR of T2D was 1·73 (95% confidence interval (CI) 1·54 - 1·94) for current versus never smoking, and 38·3% of the excess risk was mediated by the metabolic signature. The metabolic signature and its mediation role were replicated in TwinGene. The metabolic signature was associated with T2D (HR: 1·61, CI 1·46 - 1·77 for values above vs. below median), with evidence of interaction with GRS-T2D (RERI: 0·81, CI: 0·23 - 1·38) and GRS-IR (RERI 0·47, CI: 0·02 - 0·92).

INTERPRETATION

The increased risk of T2D in smokers may be mediated through effects on the metabolome, and the influence of such metabolic alterations on diabetes risk may be amplified in individuals with genetic susceptibility to T2D or insulin resistance.

Global burden and strength of evidence for 88 risk factors in 204 countries and 811 subnational locations, 1990-2021: a systematic analysis for the Global Burden of Disease Study 2021

BACKGROUND

Understanding the health consequences associated with exposure to risk factors is necessary to inform public health policy and practice. To systematically quantify the contributions of risk factor exposures to specific health outcomes, the Global Burden of Diseases, Injuries, and Risk Factors Study (GBD) 2021 aims to provide comprehensive estimates of exposure levels, relative health risks, and attributable burden of disease for 88 risk factors in 204 countries and territories and 811 subnational locations, from 1990 to 2021.

METHODS

The GBD 2021 risk factor analysis used data from 54 561 total distinct sources to produce epidemiological estimates for 88 risk factors and their associated health outcomes for a total of 631 risk-outcome pairs. Pairs were included on the basis of data-driven determination of a risk-outcome association. Age-sex-location-year-specific estimates were generated at global, regional, and national levels. Our approach followed the comparative risk assessment framework predicated on a causal web of hierarchically organised, potentially combinative, modifiable risks. Relative risks (RRs) of a given outcome occurring as a function of risk factor exposure were estimated separately for each risk-outcome pair, and summary exposure values (SEVs), representing risk-weighted exposure prevalence, and theoretical minimum risk exposure levels (TMRELs) were estimated for each risk factor. These estimates were used to calculate the population attributable fraction (PAF; ie, the proportional change in health risk that would occur if exposure to a risk factor were reduced to the TMREL). The product of PAFs and disease burden associated with a given outcome, measured in disability-adjusted life-years (DALYs), yielded measures of attributable burden (ie, the proportion of total disease burden attributable to a particular risk factor or combination of risk factors). Adjustments for mediation were applied to account for relationships involving risk factors that act indirectly on outcomes via intermediate risks. Attributable burden estimates were stratified by Socio-demographic Index (SDI) quintile and presented as counts, age-standardised rates, and rankings. To complement estimates of RR and attributable burden, newly developed burden of proof risk function (BPRF) methods were applied to yield supplementary, conservative interpretations of risk-outcome associations based on the consistency of underlying evidence, accounting for unexplained heterogeneity between input data from different studies. Estimates reported represent the mean value across 500 draws from the estimate's distribution, with 95% uncertainty intervals (UIs) calculated as the 2·5th and 97·5th percentile values across the draws.

FINDINGS

Among the specific risk factors analysed for this study, particulate matter air pollution was the leading contributor to the global disease burden in 2021, contributing 8·0% (95% UI 6·7-9·4) of total DALYs, followed by high systolic blood pressure (SBP; 7·8% [6·4-9·2]), smoking (5·7% [4·7-6·8]), low birthweight and short gestation (5·6% [4·8-6·3]), and high fasting plasma glucose (FPG; 5·4% [4·8-6·0]). For younger demographics (ie, those aged 0-4 years and 5-14 years), risks such as low birthweight and short gestation and unsafe water, sanitation, and handwashing (WaSH) were among the leading risk factors, while for older age groups, metabolic risks such as high SBP, high body-mass index (BMI), high FPG, and high LDL cholesterol had a greater impact. From 2000 to 2021, there was an observable shift in global health challenges, marked by a decline in the number of all-age DALYs broadly attributable to behavioural risks (decrease of 20·7% [13·9-27·7]) and environmental and occupational risks (decrease of 22·0% [15·5-28·8]), coupled with a 49·4% (42·3-56·9) increase in DALYs attributable to metabolic risks, all reflecting ageing populations and changing lifestyles on a global scale. Age-standardised global DALY rates attributable to high BMI and high FPG rose considerably (15·7% [9·9-21·7] for high BMI and 7·9% [3·3-12·9] for high FPG) over this period, with exposure to these risks increasing annually at rates of 1·8% (1·6-1·9) for high BMI and 1·3% (1·1-1·5) for high FPG. By contrast, the global risk-attributable burden and exposure to many other risk factors declined, notably for risks such as child growth failure and unsafe water source, with age-standardised attributable DALYs decreasing by 71·5% (64·4-78·8) for child growth failure and 66·3% (60·2-72·0) for unsafe water source. We separated risk factors into three groups according to trajectory over time: those with a decreasing attributable burden, due largely to declining risk exposure (eg, diet high in trans-fat and household air pollution) but also to proportionally smaller child and youth populations (eg, child and maternal malnutrition); those for which the burden increased moderately in spite of declining risk exposure, due largely to population ageing (eg, smoking); and those for which the burden increased considerably due to both increasing risk exposure and population ageing (eg, ambient particulate matter air pollution, high BMI, high FPG, and high SBP).

INTERPRETATION

Substantial progress has been made in reducing the global disease burden attributable to a range of risk factors, particularly those related to maternal and child health, WaSH, and household air pollution. Maintaining efforts to minimise the impact of these risk factors, especially in low SDI locations, is necessary to sustain progress. Successes in moderating the smoking-related burden by reducing risk exposure highlight the need to advance policies that reduce exposure to other leading risk factors such as ambient particulate matter air pollution and high SBP. Troubling increases in high FPG, high BMI, and other risk factors related to obesity and metabolic syndrome indicate an urgent need to identify and implement interventions.

FUNDING

Bill & Melinda Gates Foundation.

Global burden and strength of evidence for 88 risk factors in 204 countries and 811 subnational locations, 1990-2021: a systematic analysis for the Global Burden of Disease Study 2021

BACKGROUND

Understanding the health consequences associated with exposure to risk factors is necessary to inform public health policy and practice. To systematically quantify the contributions of risk factor exposures to specific health outcomes, the Global Burden of Diseases, Injuries, and Risk Factors Study (GBD) 2021 aims to provide comprehensive estimates of exposure levels, relative health risks, and attributable burden of disease for 88 risk factors in 204 countries and territories and 811 subnational locations, from 1990 to 2021.

METHODS

The GBD 2021 risk factor analysis used data from 54 561 total distinct sources to produce epidemiological estimates for 88 risk factors and their associated health outcomes for a total of 631 risk-outcome pairs. Pairs were included on the basis of data-driven determination of a risk-outcome association. Age-sex-location-year-specific estimates were generated at global, regional, and national levels. Our approach followed the comparative risk assessment framework predicated on a causal web of hierarchically organised, potentially combinative, modifiable risks. Relative risks (RRs) of a given outcome occurring as a function of risk factor exposure were estimated separately for each risk-outcome pair, and summary exposure values (SEVs), representing risk-weighted exposure prevalence, and theoretical minimum risk exposure levels (TMRELs) were estimated for each risk factor. These estimates were used to calculate the population attributable fraction (PAF; ie, the proportional change in health risk that would occur if exposure to a risk factor were reduced to the TMREL). The product of PAFs and disease burden associated with a given outcome, measured in disability-adjusted life-years (DALYs), yielded measures of attributable burden (ie, the proportion of total disease burden attributable to a particular risk factor or combination of risk factors). Adjustments for mediation were applied to account for relationships involving risk factors that act indirectly on outcomes via intermediate risks. Attributable burden estimates were stratified by Socio-demographic Index (SDI) quintile and presented as counts, age-standardised rates, and rankings. To complement estimates of RR and attributable burden, newly developed burden of proof risk function (BPRF) methods were applied to yield supplementary, conservative interpretations of risk-outcome associations based on the consistency of underlying evidence, accounting for unexplained heterogeneity between input data from different studies. Estimates reported represent the mean value across 500 draws from the estimate's distribution, with 95% uncertainty intervals (UIs) calculated as the 2·5th and 97·5th percentile values across the draws.

FINDINGS

Among the specific risk factors analysed for this study, particulate matter air pollution was the leading contributor to the global disease burden in 2021, contributing 8·0% (95% UI 6·7-9·4) of total DALYs, followed by high systolic blood pressure (SBP; 7·8% [6·4-9·2]), smoking (5·7% [4·7-6·8]), low birthweight and short gestation (5·6% [4·8-6·3]), and high fasting plasma glucose (FPG; 5·4% [4·8-6·0]). For younger demographics (ie, those aged 0-4 years and 5-14 years), risks such as low birthweight and short gestation and unsafe water, sanitation, and handwashing (WaSH) were among the leading risk factors, while for older age groups, metabolic risks such as high SBP, high body-mass index (BMI), high FPG, and high LDL cholesterol had a greater impact. From 2000 to 2021, there was an observable shift in global health challenges, marked by a decline in the number of all-age DALYs broadly attributable to behavioural risks (decrease of 20·7% [13·9-27·7]) and environmental and occupational risks (decrease of 22·0% [15·5-28·8]), coupled with a 49·4% (42·3-56·9) increase in DALYs attributable to metabolic risks, all reflecting ageing populations and changing lifestyles on a global scale. Age-standardised global DALY rates attributable to high BMI and high FPG rose considerably (15·7% [9·9-21·7] for high BMI and 7·9% [3·3-12·9] for high FPG) over this period, with exposure to these risks increasing annually at rates of 1·8% (1·6-1·9) for high BMI and 1·3% (1·1-1·5) for high FPG. By contrast, the global risk-attributable burden and exposure to many other risk factors declined, notably for risks such as child growth failure and unsafe water source, with age-standardised attributable DALYs decreasing by 71·5% (64·4-78·8) for child growth failure and 66·3% (60·2-72·0) for unsafe water source. We separated risk factors into three groups according to trajectory over time: those with a decreasing attributable burden, due largely to declining risk exposure (eg, diet high in trans-fat and household air pollution) but also to proportionally smaller child and youth populations (eg, child and maternal malnutrition); those for which the burden increased moderately in spite of declining risk exposure, due largely to population ageing (eg, smoking); and those for which the burden increased considerably due to both increasing risk exposure and population ageing (eg, ambient particulate matter air pollution, high BMI, high FPG, and high SBP).

INTERPRETATION

Substantial progress has been made in reducing the global disease burden attributable to a range of risk factors, particularly those related to maternal and child health, WaSH, and household air pollution. Maintaining efforts to minimise the impact of these risk factors, especially in low SDI locations, is necessary to sustain progress. Successes in moderating the smoking-related burden by reducing risk exposure highlight the need to advance policies that reduce exposure to other leading risk factors such as ambient particulate matter air pollution and high SBP. Troubling increases in high FPG, high BMI, and other risk factors related to obesity and metabolic syndrome indicate an urgent need to identify and implement interventions.

FUNDING

Bill & Melinda Gates Foundation.

Estimating effects of whole grain consumption on type 2 diabetes, colorectal cancer and cardiovascular disease: a burden of proof study

BACKGROUND

Previous studies on whole grain consumption had inconsistent findings and lacked quantitative assessments of evidence quality. Therefore, we aimed to summarize updated findings using the Burden of Proof analysis (BPRF) to investigate the relationship of whole grain consumption on type 2 diabetes (T2D), colorectal cancer (CRC), stroke, and ischemic heart disease (IHD).

METHODS

We conducted a literature search in the Medline and Web of Science up to June 12, 2023, to identify related cohort studies and systematic reviews. The mean RR (relative risk) curve and uncertainty intervals (UIs), BPRF function, risk-outcome score (ROS), and the theoretical minimum risk exposure level (TMREL) were estimated to evaluate the level of four risk-outcome pairs.

RESULTS

In total, 27 prospective cohorts were included in our analysis. Consuming whole grain at the range of TMREL (118.5-148.1 g per day) was associated with lower risks: T2D (declined by 37.3%, 95% UI: 5.8 to 59.5), CRC (declined by 17.3%, 6.5 to 27.7), stroke (declined by 21.8%, 7.3 to 35.1), and IHD (declined by 36.9%, 7.1 to 58.0). For all outcomes except stroke, we observed a non-linear, monotonic decrease as whole grain consumption increased; For stroke, it followed a J-shaped curve (the greatest decline in the risk of stroke at consuming 100 g whole grain for a day). The relationships between whole grain consumption and four diseases are all two-star pairs (ROS: 0.087, 0.068, 0.062, 0.095 for T2D, CRC, stroke, and IHD, respectively).

CONCLUSION

Consuming 100 g of whole grains per day offers broad protective benefits. However, exceeding this threshold may diminish the protective effects against stroke. Our findings endorse replacing refined grains with whole grains as the main source of daily carbohydrates. REGISTRY AND REGISTRY NUMBER FOR SYSTEMATIC REVIEWS OR META-ANALYSES: We have registered our research in PROSPERO, and the identifier of our meta-analyses is CRD42023447345.

Smoking is associated with higher risk of contracting bacterial infection and pneumonia, intensive care unit admission and death

BACKGROUND

Smoking has been associated with a higher risk of contracting pneumonia, but contradictory results have shown that smoking may or may not decrease the risk of dying in pneumonia. The aim of this study is to investigate how smoking is associated with contracting any infection and pneumonia and death.

METHOD AND FINDINGS

Participants were drawn from the population-based Cohort of Swedish Men and the Swedish Mammography Cohort, which are representative of the Swedish population. Participants have answered detailed lifestyle questionnaires and have been followed in national registers, such as the Patient Register, Cause of Death register and Swedish Intensive Care Registry. The risks of contracting infection and pneumonia or dying in infection and pneumonia were assessed using Cox regression. Of 62,902 cohort participants, 25,297 contracted an infection of which 4,505 died; and 10,471 contracted pneumonia of which 2,851 died. Compared to never smokers, former smokers at baseline had hazard ratio (HR) 1.08 (95% confidence interval (CI) 1.05-1.12) of contracting and HR 1.19 (95% CI 1.11-1.28) of dying in infection and HR 1.17 (95% CI 1.12-1.23) of contracting and HR 1.16 (95% CI 1.06-1.27) of dying in pneumonia during follow-up. Compared to never smokers, current smokers at baseline had HR 1.17 (95% CI 1.13-1.21) of contracting infection and HR 1.64 (95% CI 1.52-1.77) dying in infection; HR 1.42 (95% CI 1.35-1.49) of contracting pneumonia and HR 1.70 (95% CI 1.55-1.87) of dying in pneumonia during follow-up. The risk of contracting and dying in infection and pneumonia increased in a dose-response manner with number of pack years smoked and decreased with years since smoking cessation.

CONCLUSION

Smoking is associated with contracting and dying in any infection and pneumonia and the risk increases with pack years smoked, highlighting the importance of both primary prevention and smoking cessation.

Differences across the lifespan between females and males in the top 20 causes of disease burden globally: a systematic analysis of the Global Burden of Disease Study 2021

BACKGROUND

Sex and gender shape health. There is a growing body of evidence focused on comprehensively and systematically examining the magnitude, persistence, and nature of differences in health between females and males. Here, we aimed to quantify differences in the leading causes of disease burden between females and males across ages and geographies.

METHODS

We used the Global Burden of Disease Study 2021 to compare disability-adjusted life-year (DALY) rates for females and males for the 20 leading causes of disease burden for individuals older than 10 years at the global level and across seven world regions, between 1990 and 2021. We present absolute and relative differences in the cause-specific DALY rates between females and males.

FINDINGS

Globally, females had a higher burden of morbidity-driven conditions with the largest differences in DALYs for low back pain (with 478·5 [95% uncertainty interval 346·3-632·8] more DALYs per 100 000 individuals among females than males), depressive disorders (348·3 [241·3-471·0]), and headache disorders (332·9 [48·3-731·9]), whereas males had higher DALY rates for mortality-driven conditions with the largest differences in DALYs for COVID-19 (with 1767·8 [1581·1-1943·5] more DALYs per 100 000 among males than females), road injuries (1012·2 [934·1-1092·9]), and ischaemic heart disease (1611·8 [1405·0-1856·3]). The differences between sexes became larger over age and remained consistent over time for all conditions except HIV/AIDS. The largest difference in HIV/AIDS was observed among those aged 25-49 years in sub-Saharan Africa with 1724·8 (918·8-2613·7) more DALYs per 100 000 among females than males.

INTERPRETATION

The notable health differences between females and males point to an urgent need for policies to be based on sex-specific and age-specific data. It is also important to continue promoting gender-sensitive research, and ultimately, implement interventions that not only reduce the burden of disease but also achieve greater health equity.

FUNDING

Bill & Melinda Gates Foundation.

The Product Science of Electrically Heated Tobacco Products: An Updated Narrative Review of the Scientific Literature

Heated tobacco products represent a novel category of tobacco products in which a tobacco consumable is heated to a temperature that releases nicotine from the tobacco leaf but not to a temperature sufficient to cause combustion. Heated tobacco products may therefore have the potential to be a less harmful alternative for adult smokers who would otherwise continue to smoke cigarettes, as their use should result in exposure to substantially fewer and lower levels of toxicants. This update represents a two-year extension to our previous narrative review, which covered peer-reviewed journal articles published up to August 31, 2021. The scientific evidence published between 2021 and 2023 continues to indicate that aerosols produced from heated tobacco products contain fewer and substantially lower levels of harmful and potentially harmful constituents and that these observed reductions consistently translate to reduced biological effects in both in vitro and in vivo toxicological studies. Biomarker and clinical data from studies in which product use is controlled within a clinical setting continue to suggest changes in levels of biomarkers of exposure, biomarkers of potential harm, and clinical endpoints indicating the potential for reduced harm with switching to exclusive use of heated tobacco products in adult smokers. Overall, the available peer-reviewed scientific evidence continues to indicate that heated tobacco products offer promise as a potentially less harmful alternative to cigarettes, and as such, the conclusions of our original narrative review remain valid.

Impact of smoking cessation duration on lung cancer mortality: A systematic review and meta-analysis

BACKGROUND

Smoking history is a heterogeneous situation for different populations, and numerous studies suggest that smoking cessation is conducive to reduce the mortality of lung cancer. However, no quantitative meta-analysis regarding smoking cessation duration based on different populations has demonstrated it clearly.

METHODS

We systematically searched four electronic databases (PubMed, Embase, the Cochrane Central Register of Controlled Trials, and Scoups) till February 2023. Eligible studies reported the association between lung cancer survival and duration of smoking cessation. Additionally, we stratified the study population according to whether they had lung cancer at the time they quit smoking. Studies were pooled with the random-effects model.

RESULTS

Out of the 11,361 potential studies initially identified, we included 24 studies involving 969,560 individuals in our analysis. Lung cancer mortality varied across two groups: general quitters and peri-diagnosis quitters. For general quitters, those who had quit smoking for less than 10 years exhibited an RR of 0.64 (95% CI [0.55-0.76]), while those who quit for 10-20 years had an RR of 0.33 (0.25-0.43), over 20 years had an RR of 0.16 (0.11-0.24), and never-smokers had an RR at 0.11 (0.07-0.15). Among peri-diagnosis quitters, the 1-year Overall Survival (OS) showed an RR of 0.80 (0.67-0.96), the 2-year OS had an RR of 0.89 (0.80-0.98), the 3-year OS had an RR of 0.93 (0.84-1.03), and the 5-year OS had an RR of 0.85 (0.76-0.96).

CONCLUSIONS

Earlier and longer smoking cessation is associated with reduced lung cancer mortality, no matter in which cessation stage for two different populations.

EIF4A3 modulated circ_000999 promotes epithelial-mesenchymal transition in cadmium-induced malignant transformation through the miR-205-5p/ZEB1 axis

Cadmium (Cd) is an accumulative toxic metal which poses a serious threat to human health, even in trace amounts. One of the most important steps in the pathophysiology of lung cancer (LC) is the epithelial-mesenchymal transition (EMT). In this investigation, a cell malignant transformation model was established by exposing human bronchial epithelial cells (16HBE) to a low dose of Cd for 30 weeks, after which a highly expressed circular RNA (circ_000999) was identified. Cd-induced EMT was clearly observed in rat lungs and 16HBE cells, which was further enhanced following circ_000999-overexpression. Furthermore, upregulated EIF4A3 interacted with the parental gene AGTPBP1 to promote high expression of circ_000999. Subsequent experiments confirmed that circ_000999 could regulate the EMT process by competitively binding miR-205-5p and inhibiting its activity, consequently upregulating expression of zinc finger E-box binding protein 1 (ZEB1). Importantly, the circ_000999 expression level in LC tissues was significantly increased, exhibiting a strong correlation with EMT indicators. Overall, these findings provide a new objective and research direction for reversing lung EMT and subsequent treatment and prevention of LC.

Assessing the Impact of a Health Education Anti-Smoking Program for Students: A Follow-Up Investigation

In this follow-up study, we aimed to assess the effectiveness of the "I do not smoke, I exercise" anti-smoking preventive health education program. The program was based on the theory of planned behavior supplemented with life skills teaching and targeted at high school students. The intervention comprised ten one-hour online sessions, administered by physical education instructors. The study cohort comprised 222 students (109 boys, 113 girls) from 11 secondary schools, with an average age of 16.42 ± 1.36 years. Data collection involved pre- and post-intervention self-assessment questionnaires. The examined variables included attitudes towards smoking, intention to smoke, subjective norm, perceived behavioral control (PBC), knowledge about smoking, smoking behavior, exercise behavior, attitudes toward the program's implementation, and satisfaction with the program. A separate paired samples t-test revealed a significant improvement in students' knowledge about smoking (t217 = -5.605, p < 0.001, d = 0.38) and perceived behavioral control (t220 = -2.166, p < 0.05, d = 0.15) following the intervention. However, no significant changes were observed in the remaining variables. In addition, students' overall satisfaction with the implementation of the present health education program was high (M = 5.72 ± 1.39). These findings suggest that the health education smoking prevention intervention incorporates techniques and strategies that influence the perceived behavioral control variable, emphasizing students' strong interest in educationally theorized programs integrating technology into their design. Future studies should consider further examination of tobacco control strategies within the high school context.

Nicotinic Acetylcholine Receptors in Glial Cells as Molecular Target for Parkinson's Disease

Parkinson's disease (PD) is a progressive neurodegenerative disease characterized by resting tremor, bradykinesia, rigidity, and postural instability that also includes non-motor symptoms such as mood dysregulation. Dopamine (DA) is the primary neurotransmitter involved in this disease, but cholinergic imbalance has also been implicated. Current intervention in PD is focused on replenishing central DA, which provides remarkable temporary symptomatic relief but does not address neuronal loss and the progression of the disease. It has been well established that neuronal nicotinic cholinergic receptors (nAChRs) can regulate DA release and that nicotine itself may have neuroprotective effects. Recent studies identified nAChRs in nonneuronal cell types, including glial cells, where they may regulate inflammatory responses. Given the crucial role of neuroinflammation in dopaminergic degeneration and the involvement of microglia and astrocytes in this response, glial nAChRs may provide a novel therapeutic target in the prevention and/or treatment of PD. In this review, following a brief discussion of PD, we focus on the role of glial cells and, specifically, their nAChRs in PD pathology and/or treatment.

Effects of education on adult mortality: a global systematic review and meta-analysis

BACKGROUND

The positive effect of education on reducing all-cause adult mortality is known; however, the relative magnitude of this effect has not been systematically quantified. The aim of our study was to estimate the reduction in all-cause adult mortality associated with each year of schooling at a global level.

METHODS

In this systematic review and meta-analysis, we assessed the effect of education on all-cause adult mortality. We searched PubMed, Web of Science, Scopus, Embase, Global Health (CAB), EconLit, and Sociology Source Ultimate databases from Jan 1, 1980, to May 31, 2023. Reviewers (LD, TM, HDV, CW, IG, AG, CD, DS, KB, KE, and AA) assessed each record for individual-level data on educational attainment and mortality. Data were extracted by a single reviewer into a standard template from the Global Burden of Diseases, Injuries, and Risk Factors Study. We excluded studies that relied on case-crossover or ecological study designs to reduce the risk of bias from unlinked data and studies that did not report key measures of interest (all-cause adult mortality). Mixed-effects meta-regression models were implemented to address heterogeneity in referent and exposure measures among studies and to adjust for study-level covariates. This study was registered with PROSPERO (CRD42020183923).

FINDINGS

17 094 unique records were identified, 603 of which were eligible for analysis and included data from 70 locations in 59 countries, producing a final dataset of 10 355 observations. Education showed a dose-response relationship with all-cause adult mortality, with an average reduction in mortality risk of 1·9% (95% uncertainty interval 1·8-2·0) per additional year of education. The effect was greater in younger age groups than in older age groups, with an average reduction in mortality risk of 2·9% (2·8-3·0) associated with each additional year of education for adults aged 18-49 years, compared with a 0·8% (0·6-1·0) reduction for adults older than 70 years. We found no differential effect of education on all-cause mortality by sex or Socio-demographic Index level. We identified publication bias (p<0·0001) and identified and reported estimates of between-study heterogeneity.

INTERPRETATION

To our knowledge, this is the first systematic review and meta-analysis to quantify the importance of years of schooling in reducing adult mortality, the benefits of which extend into older age and are substantial across sexes and economic contexts. This work provides compelling evidence of the importance of education in improving life expectancy and supports calls for increased investment in education as a crucial pathway for reducing global inequities in mortality.

FUNDING

Research Council of Norway and the Bill & Melinda Gates Foundation.

Evaluating causal influence of maternal educational attainment on offspring birthweight via observational study and Mendelian randomization analyses

Background

Although extensive discussions on the influence of maternal educational attainment on offspring birthweight, the conclusion remains controversial, and it is challenging to comprehensively assess the causal association between them.

Methods

To estimate effect of maternal educational attainment on the birthweight of first child, we first conducted an individual-level analysis with UK Biobank participants of white ancestry (n = 208,162). We then implemented Mendelian randomization (MR) methods including inverse variance weighted (IVW) MR and multivariable MR to assess the causal relation between maternal education and maternal-specific birthweight. Finally, using the UK Biobank parent-offspring trio data (n = 618), we performed a polygenic score based MR to simultaneously adjust for confounding effects of fetal-specific birthweight and paternal educational attainment. We also conducted simulations for power evaluation and sensitivity analyses for horizontal pleiotropy of instruments.

Results

We observed that birthweight of first child was positively influenced by maternal education, with 7 years of maternal education as the reference, adjusted effect = 44.8 (95%CIs 38.0-51.6, P = 6.15 × 10-38), 54.9 (95%CIs 47.6-62.2, P = 4.21 × 10-128), and 89.4 (95%CIs 82.1-96.7, P = 4.28 × 10-34) for 10, 15 and 20 years of maternal educational attainment, respectively. A causal relation between maternal education and offspring birthweight was revealed by IVW MR (estimated effect = 0.074 for one standard deviation increase in maternal education years, 95%CIs 0.054-0.093, P = 2.56 × 10-13) and by complementary MR methods. This connection was not substantially affected by paternal education or horizontal pleiotropy. Further, we found a positive but insignificant causal association (adjusted effect = 24.0, 95%CIs -150.1-198.1, P = 0.787) between maternal education and offspring birthweight after simultaneously controlling for fetal genome and paternal education; this null causality was largely due to limited power of small sample sizes of parent-offspring trios.

Conclusion

This study offers supportive evidence for a causal association between maternal education and offspring birthweight, highlighting the significance of enhancing maternal education to prevent low birthweight.

An immunogenetic basis for lung cancer risk

Cancer risk is influenced by inherited mutations, DNA replication errors, and environmental factors. However, the influence of genetic variation in immunosurveillance on cancer risk is not well understood. Leveraging population-level data from the UK Biobank and FinnGen, we show that heterozygosity at the human leukocyte antigen (HLA)-II loci is associated with reduced lung cancer risk in smokers. Fine-mapping implicated amino acid heterozygosity in the HLA-II peptide binding groove in reduced lung cancer risk, and single-cell analyses showed that smoking drives enrichment of proinflammatory lung macrophages and HLA-II+ epithelial cells. In lung cancer, widespread loss of HLA-II heterozygosity (LOH) favored loss of alleles with larger neopeptide repertoires. Thus, our findings nominate genetic variation in immunosurveillance as a critical risk factor for lung cancer.

Health effects associated with chewing tobacco: a Burden of Proof study

Chewing tobacco use poses serious health risks; yet it has not received as much attention as other tobacco-related products. This study synthesizes existing evidence regarding the health impacts of chewing tobacco while accounting for various sources of uncertainty. We conducted a systematic review and meta-analysis of chewing tobacco and seven health outcomes, drawing on 103 studies published from 1970 to 2023. We use a Burden of Proof meta-analysis to generate conservative risk estimates and find weak-to-moderate evidence that tobacco chewers have an increased risk of stroke, lip and oral cavity cancer, esophageal cancer, nasopharynx cancer, other pharynx cancer, and laryngeal cancer. We additionally find insufficient evidence of an association between chewing tobacco and ischemic heart disease. Our findings highlight a need for policy makers, researchers, and communities at risk to devote greater attention to chewing tobacco by both advancing tobacco control efforts and investing in strengthening the existing evidence base.

Sex differences in chronic obstructive pulmonary disease characteristics: the Korea National Health and Nutrition Examination Survey 2007-2018

BACKGROUND/AIMS

Chronic obstructive pulmonary disease (COPD) is less prevalent in females than males, but it affects mortality in females. There may be sex differences in the clinical characteristics of COPD.

METHODS

We analyzed the Korea National Health and Nutrition Examination Survey dataset from 2007 to 2018. We compared the clinical characteristics and comorbidities in subjects with COPD according to sex. We adjusted the multivariate logistic regression of lung cancer prevalence according to COPD and sex by age and smoking amount.

RESULTS

Females with COPD tended to be older than males with COPD (64.1 ± 0.4 yr vs. 62.3 ± 0.2 yr, respectively, p < 0.001). Approximately 89% of males with COPD had a smoking history, while 86% of females with COPD were non-smokers (p < 0.001). Household income was lower (p < 0.001) and asthma and overall malignancy were more prevalent in females with COPD than males with COPD (25.5 vs. 11.6%, respectively, p < 0.001; (6.3 vs. 5.4%, respectively, p < 0.001). However, lung cancer was more common in males with COPD than females with COPD (0.9 vs. 0.1%, respectively, p < 0.001). Lung cancer prevalence increased in males with moderate COPD compared to subjects without COPD (OR, 4.409; 95% CI, 1.741-9.419).

CONCLUSION

Females with COPD had a lower smoking rate, household income, and lung cancer prevalence than males with COPD. More active COPD screening is needed for women of low socioeconomic status, even if they do not smoke.

Health effects associated with exposure to secondhand smoke: a Burden of Proof study

Despite a gradual decline in smoking rates over time, exposure to secondhand smoke (SHS) continues to cause harm to nonsmokers, who are disproportionately children and women living in low- and middle-income countries. We comprehensively reviewed the literature published by July 2022 concerning the adverse impacts of SHS exposure on nine health outcomes. Following, we quantified each exposure-response association accounting for various sources of uncertainty and evaluated the strength of the evidence supporting our analyses using the Burden of Proof Risk Function methodology. We found all nine health outcomes to be associated with SHS exposure. We conservatively estimated that SHS increases the risk of ischemic heart disease, stroke, type 2 diabetes and lung cancer by at least around 8%, 5%, 1% and 1%, respectively, with the evidence supporting these harmful associations rated as weak (two stars). The evidence supporting the harmful associations between SHS and otitis media, asthma, lower respiratory infections, breast cancer and chronic obstructive pulmonary disease was weaker (one star). Despite the weak underlying evidence for these associations, our results reinforce the harmful effects of SHS on health and the need to prioritize advancing efforts to reduce active and passive smoking through a combination of public health policies and education initiatives.

Sex differences in frailty among older adults

By definition, aging is a natural, gradual and continuous process. On the other hand, frailty reflects the increase in vulnerability to stressors and shortens the time without disease (health span) while longevity refers to the length of life (lifespan). The average life expectancy has significantly increased during the last few decades. A longer lifespan has been accompanied by an increase in frailty and decreased independence in older adults, with major differences existing between men and women. For example, women tend to live longer than men but also experience higher rates of frailty and disability. Sex differences prevent optimization of lifestyle interventions and therapies to effectively prevent frailty. Sex differences in frailty and aging are rooted in a complex interplay between uncontrollable (genetic, epigenetic, physiological), and controllable factors (psychosocial and lifestyle factors). Thus, understanding the underlying causes of sex differences in frailty and aging is essential for developing personalized interventions to promote healthy aging and improve quality of life in older men and women. In this review, we have discussed the key contributors and knowledge gaps related to sex differences in aging and frailty.

Health effects associated with exposure to intimate partner violence against women and childhood sexual abuse: a burden of proof study

The health impacts of intimate partner violence against women and childhood sexual abuse are not fully understood. Here we conducted a systematic review by comprehensively searching seven electronic databases for literature on intimate partner violence-associated and childhood sexual abuse-associated health effects. Following the burden of proof methodology, we evaluated the evidence strength linking intimate partner violence and/or childhood sexual abuse to health outcomes supported by at least three studies. Results indicated a moderate association of intimate partner violence with major depressive disorder and with maternal abortion and miscarriage (63% and 35% increased risk, respectively). HIV/AIDS, anxiety disorders and self-harm exhibited weak associations with intimate partner violence. Fifteen outcomes were evaluated for their relationship to childhood sexual abuse, which was shown to be moderately associated with alcohol use disorders and with self-harm (45% and 35% increased risk, respectively). Associations between childhood sexual abuse and 11 additional health outcomes, such as asthma and type 2 diabetes mellitus, were found to be weak. Although our understanding remains limited by data scarcity, these health impacts are larger in magnitude and more extensive than previously reported. Renewed efforts on violence prevention and evidence-based approaches that promote healing and ensure access to care are necessary.

Red Meat Consumption and Cancer Risk: A Systematic Analysis of Global Data

The association between red meat consumption and cancer risk remains a controversy. In this study, we systematically collected and analyzed global data (from Our World in Data and Global Cancer Observatory) to investigate this association for the first time. Our results confirmed significant positive associations between red meat consumption (RMC) and overall cancer incidence (0.798, p < 0.001), or colorectal cancer incidence (0.625, p < 0.001). Several previously unreported cancer types linked to RMC were also unveiled. Gross domestic product (GDP) per capita were found to have an impact on this association. However, even after controlling it, RMC remained significantly associated with cancer incidence (0.463, p < 0.001; 0.592, p < 0.001). Meanwhile, after controlling GDP per capita, the correlation coefficients between white meat consumption and overall cancer incidence were found to be much lower and insignificant, at 0.089 (p = 0.288) for poultry consumption and at -0.055 (p = 0.514) for seafood and fish consumption. Notably, an interesting comparison was performed between changes of colorectal cancer incidence and RMC in many countries and regions. A lag of 15-20 years was found, implying causality between RMC and cancer risk. Our findings will contribute to the development of more rational meat consumption concept.