Social Inequalities in Secondhand Smoke Among Japanese Non-smokers: A Cross-Sectional Study

Secondhand Aerosol Exposure From Heated Tobacco Products and Its Socioeconomic Inequalities in Japan: The JASTIS Study 2017-2020

INTRODUCTION

The growing use of heated tobacco products (HTPs) has raised concerns about secondhand aerosol (SHA) from HTPs, but few studies have been reported on it. This study aimed to investigate the trends in SHA exposure and their socioeconomic inequalities in Japan.

METHODS

The prevalence of SHA exposure from 2017 to 2020 was estimated using longitudinal internet survey data of 5221 participants, aged 20-69 years in 2017 (baseline), with adjustments using inverse probability weighting for "being a participant in an internet survey". Multivariable modified Poisson regression models were applied to examine the association between socioeconomic status (ie, educational attainment and equivalent income) at baseline and SHA exposure in 2020 with adjustments for sex and age.

RESULTS

The estimated prevalence of SHA exposure has consistently increased from 4.5% in 2017 to 10.8% in 2020. Lower educational attainment was associated with a higher risk of SHA exposure (p for trend = 0.010). The covariate-adjusted risks of SHA exposure in participants with a low-education and middle-education level were 1.57 and 1.34 times higher, respectively, than in those with a high-education level. However, significant differences in risks of SHA exposure between participants with low-, middle-, and high-income levels were not observed. Meanwhile, participants with a low-education and middle-education level also had 1.87 and 1.61 times higher risks of secondhand smoke (SHS) exposure from combustible cigarettes than those with a high-education level, respectively.

CONCLUSIONS

Our study revealed a rapid increase in SHA exposure and the existence of educational inequalities in both SHA and SHS exposure.

IMPLICATIONS

Using longitudinal internet cohort survey data, we found that the prevalence of exposure to secondhand aerosol (SHA) from heated tobacco products (HTPs) rapidly increased to 10.8% in 2020 in Japan. Furthermore, people with lower educational attainment were at higher risk of SHA exposure, suggesting that extensive educational interventions may be necessary to inform the public that although emissions from HTPs contain significantly lesser amounts of harmful and potentially harmful constituents and these compounds than cigarette smoke, they are not harmless and still entail risks, and its long-term effects are unknown. Therefore, future extensive monitoring of SHA exposure is needed.

Secondhand Smoke in the Workplace Is Associated With Depression in Korean Workers

Background

Smoking negatively affects health, and previous studies argue that secondhand smoke (SHS) has a significantly negative health effect. We investigated whether SHS in the workplace influences workers' depression.

Methods

Three years of data (2014, 2016, and 2018) from the Korean National Health and Nutrition Examination Survey were analyzed. Participants who were not current smokers were classified into the occupational SHS exposed and non-exposed groups. Multivariate logistic regression was performed to estimate odds ratios (ORs) and 95% confidence intervals (CIs) by adjusting various covariates. Stratified analysis with variables, such as year, sex, occupational classification, average working hours, was additionally performed.

Results

The crude ORs of depression was 1.51 (95% CI: 1.27–1.80), and the fully adjusted OR with all the covariates was 1.57 (95% CI: 1.30–1.88). This indicated a significant relationship between occupational SHS and depression. The ORs increased every 2 years: 1.07 (95% CI: 0.79–1.44) in 2014, 1.88 (95% CI: 1.34–2.64) in 2016, and 2.07 (95% CI: 1.43–2.99) in year 2018. Stratification analysis also showed a significant association between SHS and depression among those in the prolonged work hours group and male employees, as well as blue- and white-collar workers.

Conclusion

SHS in the workplace was significantly associated with workers' depression. Our study provides insights into the impact of exposure to SHS for workers and provides a basis for further research and policy-making in this field.

Impact of workplace smoke-free policy on secondhand smoke exposure from cigarettes and exposure to secondhand heated tobacco product aerosol during COVID-19 pandemic in Japan: the JACSIS 2020 study

OBJECTIVES

Promoting smoke-free policies is a key intervention for reducing secondhand smoke (SHS) exposure. During the COVID-19 pandemic in Japan, many indoor smoking spaces in workplaces were closed. This study aimed to reveal the association between a workplace smoke-free policy and SHS exposure among non-smoking employees, distinguishing between SHS exposure from cigarettes and exposure to secondhand heated tobacco product (HTP) aerosol, which have recently become popular in Japan.

DESIGN AND SETTING

We used data from the Japan COVID-19 and Society Internet Survey conducted in August-September 2020.

PARTICIPANTS

Among the 25 482 eligible respondents, 8196 non-smoking employees were analysed.

PRIMARY OUTCOME MEASURE

Multivariable logistic regression models were used to examine the impact of smoke-free policies in the workplace.

RESULTS

Compared with complete smoking bans, the ORs and 95% CIs for workplace SHS exposure at least once a week from cigarettes were 2.06 (95% CI: 1.60 to 2.65) for partial bans with no longer available smoking spaces, 1.92 (95% CI: 1.63 to 2.25) for partial smoking bans with still available smoking spaces and 5.33 (95% CI: 4.10 to 6.93) for no smoking bans. The corresponding ORs and 95% CIs for exposure to secondhand HTP aerosol were 4.15 (95% CI: 3.22 to 5.34), 2.24 (95% CI: 1.86 to 2.71) and 3.88 (95% CI: 2.86 to 5.26), respectively.

CONCLUSIONS

The effect of partial bans was limited, and temporary closure of smoking spaces might contribute to increased exposure to secondhand HTP aerosol. Complete smoking bans in the workplace were reaffirmed to be the best way to reduce SHS exposure from cigarettes and exposure to secondhand HTP aerosol.

Association between exposure to secondhand smoking at home and tooth loss in Japan: A cross-sectional analysis of data from the 2016 National Health and Nutrition Survey

INTRODUCTION

Tooth loss affects oral health and physical and social functions. With widespread population aging, its prevalence is increasing. Secondhand smoking is a risk factor for oral diseases; however, in Japan, there are currently no regulations restricting exposure to secondhand smoke at home. This cross-sectional study examined the association between secondhand smoking at home and tooth loss among Japanese adults.

METHODS

The study examined secondary data from the 2016 National Health and Nutrition Survey, Japan. The self-reported responses of 18812 non-smokers aged ≥20 years were analyzed. The association between exposure to secondhand smoke at home and number of teeth was examined through multiple linear regression with multiple imputation. To obtain a more normal distribution, logarithmic transformation was applied to the number of teeth that deviated substantially from a normal distribution. Adjustments were made for sex, age, occupation, household size, dental check-up within the past year, and exposure to secondhand smoke outside the home.

RESULTS

Overall, 8.4% of the respondents were exposed to secondhand smoking at home almost every day; this percentage was larger among younger respondents, who also had more teeth than the older respondents. Although the univariate linear regression did not show a positive association between exposure to secondhand smoke and tooth loss, the multivariate-adjusted analysis revealed that respondents who were exposed to secondhand smoke at home almost every day had fewer teeth (β= -0.04; 95% CI: -0.07 – -0.01).

CONCLUSIONS

The present results suggest that exposure to secondhand smoke at home increases the risk of tooth loss.

Widening Socioeconomic Inequalities in Smoking in Japan, 2001-2016

BACKGROUND

Japan is one of the world's largest tobacco epidemic countries but few studies have focused on socioeconomic inequalities. We aimed to examine whether socioeconomic inequalities in smoking have reduced in Japan in recent times.

METHODS

We analyzed data from the Comprehensive Survey of Living Conditions, a large nationally representative survey conducted every 3 years (n ≈ 700,000 per year) in Japan, during 2001-2016. Age-standardized smoking prevalence was computed based on occupational class and educational level. We calculated smoking prevalence difference (PD) and ratio (PR) of (a) manual workers versus upper non-manual workers and (b) low versus high educational level. The slope index of inequality (SII) and relative index inequality (RII) by educational level were used as inequality measures.

RESULTS

Overall smoking prevalence (25-64 years) decreased from 56.0% to 38.4% among men and from 17.0% to 13.0% among women during 2001-2016. The PD between manual and upper non-manual workers (25-64 years) increased from 11.9% (95% confidence interval [CI], 11.0-12.9%) to 14.6% (95% CI, 13.5-15.6%) during 2001-2016. In 2016, smoking prevalence (25-64 years) for low, middle, and highly educated individuals were 57.8%, 43.9%, and 27.8% for men, and 34.7%, 15.9%, and 5.6% for women, respectively. SII and RII by educational level increased among both sexes. Larger socioeconomic differences in smoking prevalence were observed in younger generations, which suggests that socioeconomic inequalities in smoking evolve in a cohort pattern.

CONCLUSIONS

Socioeconomic inequalities in smoking widened between 2001 and 2016 in Japan, which indicates that health inequalities will continue to exist in near future.

Population Attributable Fractions of Modifiable Risk Factors for Nonsyndromic Orofacial Clefts: A Prospective Cohort Study From the Japan Environment and Children's Study

Background

Population impact of modifiable risk factors on orofacial clefts is still unknown. This study aimed to estimate population attributable fractions (PAFs) of modifiable risk factors for nonsyndromic cleft lip with or without cleft palate (CL±P) and cleft palate only (CP) in Japan.

Methods

We conducted a prospective cohort study using data from the Japan Environment and Children’s Study, which recruited pregnant women from 2011 to 2014. We estimated the PAFs of maternal alcohol consumption, psychological distress, maternal active and passive smoking, abnormal body mass index (BMI) (<18.5 and ≥25 kg/m²), and non-use of a folic acid supplement during pregnancy for nonsyndromic CL±P and CP in babies.

Results

A total of 94,174 pairs of pregnant women and their single babies were included. Among them, there were 146 nonsyndromic CL±P cases and 41 nonsyndromic CP cases. The combined adjusted PAF for CL±P of the modifiable risk factors excluding maternal alcohol consumption was 34.3%. Only maternal alcohol consumption was not associated with CL±P risk. The adjusted PAFs for CL±P of psychological distress, maternal active and passive smoking, abnormal BMI, and non-use of a folic acid supplement were 1.4% (95% confidence interval [CI], −10.7 to 15.1%), 9.9% (95% CI, −7.0 to 26.9%), 10.8% (95% CI, −9.9 to 30.3%), 2.4% (95% CI, −7.5 to 14.0%), and 15.1% (95% CI, −17.8 to 41.0%), respectively. We could not obtain PAFs for CP due to the small sample size.

Conclusions

We reported the population impact of the modifiable risk factors on CL±P, but not CP. This study might be useful in planning the primary prevention of CL±P.

Using human rights measures to advance tobacco control- Japan and the Committee on the Elimination of Discrimination Against Women

Japan has made progress on tobacco control in recent years. However, every year more than 157800 Japanese citizens1 and residents die from tobacco related diseases. Tobacco is a leading cause of preventable death and is therefore a considerable obstacle to the right to health of Japanese citizens. Tobacco is a human rights and women’s and girls’ rights issue and should be considered as part of the government’s human rights obligations. Tobacco, and the actions of the tobacco industry, prevents the women and girls of Japan from enjoying the highest attainable standard of health.

Determinants of Increased Tobacco Consumption Following a Major Disaster

OBJECTIVES

Experience of a major disaster can potentially impact on tobacco consumption. Our objective was to explore the determinants of increasing tobacco consumption after the Great East Japan Earthquake (GEJE).

METHODS

We conducted a cross-sectional study using data from the Miyagi Prefectural Health Survey 2014: a total of 2632 people were randomly selected from residents aged ≥20 years in Miyagi, Japan. Of 2443 respondents (response rate = 92.8%), 551 current smokers (411 men) were included in the analysis. Odds ratios (OR) and 95% confidence interval (CI) for increasing tobacco consumption were calculated using multivariable logistic regression models including variables of age, sex, disaster-related job status change, education status, self-rated health, and age at smoking initiation.

RESULTS

After adjustments for all variables, significantly higher ORs for increasing tobacco consumption after the GEJE were observed in women (OR = 1.87; 95% CI = 1.10-3.15), 20-39 years old (OR = 5.18; 95% CI = 2.28-11.75), 40-59 years old (OR = 3.97; 95% CI = 1.76-8.94) and respondents who had lost their jobs (OR = 3.42; 95% CI = 1.06-11.05) than the counterpart categories.

CONCLUSIONS

This study found 3 determinants of increasing tobacco consumption after a major disaster: being a woman, being of working age, and experiencing disaster-related job loss.

Association Between Second-hand Smoke Exposure and Depressive Symptoms Among Japanese Adults: A Cross-sectional Study

Background

Second-hand smoke exposure has been associated with poor mental health. However, among Japanese adults, little is known about the association between second-hand smoking and depressive symptoms. We examined this association in a cross-sectional study among a Japanese general adult population sample.

Methods

Japanese adults were recruited from the Japan Multi-Institutional Collaborative Cohort Study in the Okazaki area between 2012 and 2017. Second-hand smoke exposure and smoking status were assessed using a self-administered questionnaire. Based on their frequency of exposure to second-hand smoke, non-smokers and smokers were categorized as “almost never,” “sometimes,” and “almost every day”. Depressive symptoms were defined by a Kessler 6 score ≥5 points. We performed a multivariable Poisson regression analysis to obtain adjusted prevalence ratios (PRs) and 95% confidence intervals (CIs) for depressive symptoms.

Results

Overall, 5,121 participants (4,547 non-smokers and 574 smokers) were included whose mean age was 63.6 (standard deviation [SD], 10.3) years for non-smokers and 59.33 (SD, 10.2) years for smokers. The association between second-hand smoking and depressive symptoms was significant among non-smokers, but not among smokers. Among non-smokers, PRs compared with “almost never” were 1.25 (95% CI, 1.09–1.42) for “sometimes” and 1.41 (95% CI, 1.09–1.84) for “almost every day” (P for trend <0.001); among smokers, PRs compared with “almost never” were 1.30 (95% CI, 0.82–2.06) for “sometimes” and 1.44 (95% CI, 0.90–2.33) for “almost every day” (P for trend = 0.144).

Conclusions

Second-hand smoking and depressive symptoms were associated among non-smokers. Our findings indicate the importance of tobacco smoke control for mental health.

The Causal Effect of Education on Tooth Loss: Evidence From United Kingdom Schooling Reforms

Associations between education and oral health have frequently been reported, but until now there has been no causal evidence. Exploiting exogenous variation in the duration of schooling due to 1947 and 1972 reforms in mandatory schooling in the United Kingdom, we examined the causal relationship between education and tooth loss in older age. We conducted a cross-sectional study using data from waves 3 (2006-2007), 5 (2010-2011), and 7 (2014-2015) of the English Longitudinal Study of Ageing. We used a 2-stage least squares instrumental variable approach and included 5,667 respondents (average age = 67.8 years; 44.4% were men) in the analyses, of whom 819 (14.5%) had no teeth. The schooling reforms increased the duration of education by an average of 0.624 years (95% confidence interval: 0.412, 0.835). For respondents born within ±6 years of the pivotal cohorts, a 1-year increment of education causally reduced the probability of edentulism by 9.1 (95% confidence interval: 1.5, 16.8) percentage points. The effects were stronger for the 1947 reform than for the 1972 reform. Results were robust to broadening of the cohort bandwidth and functional form of the cohort trend. The findings suggest that investment in education produces improved oral health later in life.