Residential secondhand smoke in a densely populated urban setting: a qualitative exploration of psychosocial impacts, views and experiences

Youths' awareness and attitudes towards raising the minimum legal age of smoking and passive smoking in Singapore

Objectives

Early smoking initiation has been associated with a higher risk of developing long-term smoking habit. There is a growing global consensus that demands raising the minimum legal age (MLA) for smoking as an approach to address this problem. Singapore successfully raised the MLA from 18 to 21 years in 2021. This study aimed to evaluate the awareness and attitude of multi-ethnic Asian youth (aged 15-24) on raising MLA to 21 and passive smoking.

Methods

A cross-sectional survey comprising of 23 items was circulated via a secure internet-based platform, FORMSG between September and November 2022. Data were analyzed for descriptive statistics. Categorical variables were compared for association with receptivity toward change in MLA using Chi-Squared test and multivariable logistic regression analysis using Rstudio. Post-hoc Bonferroni correction were further utilized for pairwise comparison.

Results

Majority (80.3%) of the 608 participants expressed their support for MLA 21 implementation. Participants' age was a significant variable as those aged 15-17 years old (OR = 2.1, 95%CI = 1.01-4.32, p = 0.048) showed a higher likelihood of supporting MLA implementation compared to those aged 21 and above. In addition, majority (89.8%) of them were also aware of the harmful effects of passive smoking. When it came to discouraging smoking among youth, family influence (64%) and school education (55.6%) emerged as the top strategies.

Conclusion

Most of the youth express strong support for raising the MLA to 21, with over 80% in favor of such change, reflects a significant harmony among youth in favor of tobacco-free environment.

Machine-learning model for predicting depression in second-hand smokers in cross-sectional data using the Korea National Health and Nutrition Examination Survey

Objective

Depression among non-smokers at risk of second-hand smoke (SHS) exposure has been a neglected public health concern despite their vulnerability. The objective of this study was to develop high-performance machine-learning (ML) models for the prediction of depression in non-smokers and to identify important predictors of depression for second-hand smokers.

Methods

ML algorithms were created using demographic and clinical data from the Korea National Health and Nutrition Examination Survey (KNHANES) participants from 2014, 2016, and 2018 (N = 11,463). The Patient Health Questionnaire was used to diagnose depression with a total score of 10 or higher. The final model was selected according to the area under the curve (AUC) or sensitivity. Shapley additive explanations (SHAP) were used to identify influential features.

Results

The light gradient boosting machine (LGBM) with the highest positive predictive value (PPV; 0.646) was selected as the best model among the ML algorithms, whereas the support vector machine (SVM) had the highest AUC (0.900). The most influential factors identified using the LGBM were stress perception, followed by subjective health status and quality of life. Among the smoking-related features, urine cotinine levels were the most important, and no linear relationship existed between the smoking-related features and the values of SHAP.

Conclusions

Compared with the previously developed ML models, our LGBM models achieved excellent and even superior performance in predicting depression among non-smokers at risk of SHS exposure, suggesting potential goals for depression-preventive interventions for non-smokers during public health crises.

Factors associated with Korean adolescent's e-cigarette use by the severity level of generalized anxiety disorder (GAD-7)

BACKGROUND

The use of e-cigarette among Korean adolescents is spreading with alarming rapidity, but it has not been studied along with the severity level of GAD-7. This study aims to identify adolescents' e-cigarette use and its associated factors among four different anxiety groups using the problem behavioral theory (PBT).

METHODS

A cross-sectional secondary dataset was retrieved from the 2020 Korea Youth Risk Behavior Survey. Of the total sample of 54,948, four anxiety groups were formed: minimal (score 0-4; n = 36,711), mild (score 5-9; n = 12,138), moderate (score 10-14; n = 4143), and severe (score above 15; n = 1965). A total of 11 variables were selected based on the PBT domains. Descriptive analysis, Chi-square, ANOVA, univariate analysis, and multiple linear regression analysis were performed.

RESULTS

E-cigarette use was the highest in the order of severe, mild, moderate, and minimal. While cigarette use was associated with vaping in all anxiety groups, adolescents with minimal or mild anxiety levels were more likely to be influenced by tobacco accessibility and other behavior system factors such as sexual intercourse, alcohol use, and smartphone addiction. Meanwhile, secondhand smoke exposure in public areas was only associated with those with severe anxiety levels, and secondhand smoke exposure at school was a significant factor in all anxiety groups except for those with moderate anxiety levels.

LIMITATION

Due to the nature of cross-sectional dataset, the study could not draw causal links between vaping and other identified factors, include all the necessary PBT components.

CONCLUSION

These findings underscore the need to consider different levels of anxiety when addressing the problems related to vaping among Korean adolescents.

Is secondhand smoke associated with mental health issues? A narrative review of the evidence and policy implications

Secondhand smoke (SHS) is a well-established cause of lung cancer, respiratory disease, heart disease and developmental issues in children, with an overwhelming evidence base spanning over four decades. In this narrative review, we describe studies which have also linked self-reported or cotinine-assessed SHS exposure in the home, workplace and other settings to mental health disorders including depression, suicide, anxiety, and psychological distress in children and adults, sleeping disorders, Attention Deficit Hyperactivity Disorder and behavioural issues in children, and dementia in older adults. In general, evidence indicates that SHS exposure is associated with these disorders in a dose-response manner, with higher odds reported in people who are exposed to SHS at high levels, frequently, and in the home environment. Most studies so far are cross-sectional albeit in large, nationally representative samples from various countries with a smaller number of longitudinal studies. More research is needed in this area to determine whether SHS is a direct cause of adverse mental health outcomes, and whether creating smokefree environments leads to improved mental wellbeing. In particular, more research is needed on the impact of smokefree home environments, an area which has received relatively little focus in smokefree interventions which generally target public places.

Second-hand smoke and fine particulate matter exposures among multi-unit housing residents in Singapore: A pilot study

Globally, approximately 1.2 million deaths among non-smokers are attributed to second-hand smoke (SHS) per year. Multi-unit housing is becoming the common type of residential dwelling in developed cities and the issue of neighbour SHS is of rising concern especially as 'Work From Home' became the norm during and post COVID-19 pandemic. To measure and compare the air quality of households that are exposed to SHS and unexposed households among smoking and non-smoking households in Singapore. A total of 27 households were recruited from April to August 2021. Households were categorized into smoking households with neighbour SHS, smoking households without neighbour SHS, non-smoking households with neighbour SHS, and non-smoking household without neighbour SHS. Air quality of the households was measured using calibrated particulate matter (PM_2.5) sensors for 7-16 days. Socio-demographic information and self-reported respiratory health were collected. Regression models were used to identify predictors associated with household PM_2.5 concentrations and respiratory health. Mean PM_2.5 concentration was significantly higher among non-smoking households with neighbour SHS (n = 5, mean = 22.2, IQR = 12.7) than in non-smoking household without neighbour SHS (n = 2, mean = 4.1, IQR = 5.8). Smoking activity at enclosed areas in homes had the lowest PM_2.5 concentration (n = 7 mean = 15.9, IQR = 11.0) among the three smoking locations. Exposure to higher household PM_2.5 concentration was found to be associated with poorer respiratory health. This is the first study to measure real-time PM_2.5 concentrations in households. Mean PM_2.5 concentrations was significantly higher in non-smoking households with neighbour SHS. Exposure to higher PM_2.5 concentration was associated with poorer respiratory health. A 'smoke-free residential building' policy is recommended to tackle the issue of rising neighbour SHS complaints and health concerns in densely populated multi-unit housing in Singapore. Public education campaigns should educate smokers to smoke away from the home to sufficiently protect household members from SHS.

Public Health Burden of Secondhand Smoking: Case Reports of Lung Cancer and a Literature Review

Secondhand smoke (SHS), composed of mainstream and sidestream smoke, is a known human carcinogen. It contains a variety of harmful substances at even higher concentrations than mainstream smoke itself, which is inhaled during firsthand smoking. Exposure to SHS, affecting more than a third of the worldwide population, increases the likelihood of lung cancer by roughly 30%, with specific contributions depending on the histological type of cancer. This study aimed to present the harmful potential of SHS through case reports and describe the burden of SHS via a literature review. From a collection of lung cancer case reports occurring in never smokers from the Olomouc district over the last 10 years, 2 cases with no risk factors for lung cancer except for significant exposure to SHS were identified. Both cases were of young women who lived in households where their parents smoked during childhood. They suffered from rarer histological types of lung cancer in which the association with SHS has not yet been analyzed. As the literature confirms, SHS has the most adverse effects in individuals exposed during childhood. It is necessary to both take measures to reduce the prevalence of SHS, especially among children in households and pay due attention to the smoking history of patients, including current and previous exposure to SHS, when obtaining anamnestic data. Furthermore, the effect of SHS on rarer histological types of lung cancer should be studied.