IntroductionThis study explored the association between food insecurity and tobacco product use and urine cotinine-measured smoking intensity.MethodsThis cross-sectional study included 13 705 adults representative of the Korean population. The 18-item Household Food Security Survey Module was administered to the primary food managers in households with the scores applied to household members. The use of three tobacco products—combustible cigarettes, heated tobacco products and electronic cigarettes (e-cigarettes)—was assessed. Based on the urine cotinine level, the smoking status of each participant was classified into one of three groups: non-smoker, low-intensity smoker and high-intensity smoker. Logistic regression analysis was used to determine the association between food insecurity and tobacco product use and urine cotinine-measured smoking intensity. ORs and 95% CIs were estimated.ResultsAmong the survey participants, 3.2% had mild food insecurity and 0.7% had moderate-to-severe food insecurity. Those with mild food insecurity (23.5%, OR: 1.38, 95% CI: 1.01 to 1.89) and those with moderate-to-severe food insecurity (45.1%, OR: 3.36, 95% CI: 1.87 to 6.03) compared with those with non-food insecurity (18.4%) were positively associated with combustible cigarette use. Those with moderate-to-severe food insecurity was positively associated with e-cigarette use (5.5%, OR: 3.49, 95% CI: 1.31 to 9.28). Compared with those with non-food security (7.9%), those with mild food insecurity (14.3%, OR: 1.61, 95% CI: 1.09 to 2.38) and moderate-to-severe food insecurity (22.1%, OR: 2.25, 95% CI: 1.04 to 4.86) were associated with high-intensity smoking.ConclusionFood insecurity is associated with both combustible and e-cigarette use. Those with food insecurity are associated with engagement in high-intensity smoking.

Objectives Long work hours and weekend work can negatively impact worker sleep; however, gender differences in these relationships have not been sufficiently studied. We explored the association between long work hours, weekend work, and insomnia symptoms, as well as the moderating effect of gender on this association. Methods A nationwide sample of 42,476 Korean workers (52.8% women) was analyzed. The main exposure variables were weekly work hours and monthly weekend days worked. Insomnia symptoms were measured using the Minimal Insomnia Symptom Scale. Logistic regression was used to estimate odds ratios (ORs) and confidence intervals (CIs). Results Among the study sample, 10.5% worked ≥55hours weekly and 9.6% worked ≥5 weekend days monthly. The OR (95% CI) of an association between long work hours and insomnia symptoms was 1.72 (1.48-2.00) for 49-54hours, and 2.01 (1.71-2.37) for ≥55hours among men and 1.26 (1.03-1.55) for 49-54hours, and 1.03 (0.83-1.27) for ≥55hours among women. The OR (95% CI) of an association between monthly weekend days worked and insomnia symptoms was 1.68 (1.50-1.90) for 1-4days and 1.92 (1.62-2.29) for ≥5days among men and 1.20 (1.05-1.36) for 1-4days and 1.54 (1.28-1.86) for ≥5days among women. Conclusion Long work hours and weekend work are associated with insomnia symptoms, and this association is more pronounced among men than women. Policy interventions are warranted to reduce the burden of long work hours and weekend work.

This study explored the association between workplace gender discrimination (WGD) and the onset of problematic alcohol use among female wage workers. This longitudinal study analyzed data from a nationwide sample of 4654 women, with 11,484 observations collected between 2012 and 2020. The participants reported their experiences with WGD across six dimensions: hiring practices, promotion opportunities, wage disparities, work assignments, access to training opportunities, and termination procedures. Participants were categorized into three groups based on the number of these WGD dimensions they experienced: no WGD (no experiences in any dimension), moderate WGD (experiences in 1-3 dimensions), and severe WGD (experiences in 4-6 dimensions). Problematic alcohol use was evaluated using the Cutting Down, Annoyance by Criticism, Guilty Feeling, and Eye-openers questionnaire. Generalized estimating equations were utilized to assess the relationship between the experience of WGD and the development of problematic alcohol use over a two-year period. The relative risk (RR) and its 95 % confidence interval (CI) were calculated. Among the participants, 68.8 %, 18.0 %, and 13.2 % experienced no, moderate, and severe WGD at the baseline, respectively. Compared with no experience of WGD, the RRs (95 % CI) for the onset of problematic alcohol use were 0.93 (0.50-1.71) and 2.08 (1.23-3.50) for moderate and severe WGD experience, respectively. For each WGD dimension, WGD related to promotion (RR: 1.66, 95 % CI: 1.01-2.72), wages (RR: 1.71, 95 % CI: 1.05-2.78), and termination (RR: 1.88, 95 % CI: 1.13-3.13) were related to the development of problematic alcohol use during the follow-up. WGD was associated with the onset of problematic alcohol use during the follow-up period. These findings underscore the necessity of proactive governmental and organizational initiatives to promote a gender-equitable work environment and mitigate WGD to protect women's health.

Indoor air pollutants are associated with adverse health effects in people, particularly children and older adults-the most vulnerable groups health-wise who also happen to spend much of their time in indoor environments. To contribute to knowledge on how these groups can be protected, this study sought to determine the relationships between indoor pollutants (dust endotoxins, airborne bacteria (AB), and particulate matter (PM2.5)) and environmental factors (temperature, relative humidity (RH), use of air conditioners (AC), use of windows, and season). For each pollutant, 360 samples were collected from 31 old-age nursing homes and 31 daycare centers in South Korea. The Mann-Whitney U test, Kruskal-Wallis rank sum, Spearman's rank analysis, and multivariate regression were used to determine whether there were significant differences between indoor pollutants and environmental factors. Dust endotoxin values ranged between < LOD and 632 EU/mL and between 306 and 632 CFU/m(3) for AB, and ranged from 3.9 to 32.5 g/m(3) for PM2.5. Dust endotoxin levels showed a significant relationship with RH and season in the multiple regression analysis. Periodic AC filter cleaning and exchange, as well as proper RH management in these facilities may help reduce indoor biological pollutants. The findings of this study are informative for addressing the respiratory health issues of older people and children in indoor facilities.

Background: Long working hours can negatively impact mental health. We examined the association between long working hours and problematic alcohol use among young Korean workers.Methods: We included a nationally representative sample of workers below the age of 40 from the Youth Panel between 2016 and 2020 (N = 7846; observations: 27,646). The exposure variable was working hours per week. Problematic alcohol use was assessed using the CAGE questionnaire, and generalized estimating equations were used to account for repeated measurements.Results: Observations of the participants revealed that 5 % worked < 35 h/week, 51 % worked 35-40 h/week, 24 % worked 41-48 h/week, 11 % worked 49-54 h/week, and 9 % worked >55 h/week. The prevalence of problematic alcohol use among the workers was 2 % for <35 h/week, 2 % for 35-40 h/week, 3 % for 41-48 h/ week, 4 % for 49-54 h/week, and 4 % for >55 h/week. The adjusted odds ratios (95 % confidence intervals) for the association between working hours per week and the onset of problematic alcohol use in the following year were 0.86 (0.45-1.66) for <35 h, 1.56 (1.22-1.99) for 41-48 h, 2.03 (1.49-2.75) for 49-54 h, and 1.68 (1.17-2.42) for >55 h, compared to 35-40 h. Limitations: The observational design of the study prevented the establishment of a causal relationship between working hours and the onset of problematic alcohol use.Conclusion: Long working hours were associated with the development of problematic alcohol use. Policy interventions should promote healthier drinking habits among workers with long work hours.

Background: Accurate occupation classification is essential in various fields, including policy development and epidemiological studies. This study aims to develop an occupation classification model based on DistilKoBERT. Methods: This study used data from the 5th and 6th Korean Working Conditions Surveys conducted in 2017 and 2020, respectively. A total of 99,665 survey participants, who were nationally representative of Korean workers, were included. We used natural language responses regarding their job responsibilities and occupational codes based on the Korean Standard Classification of Occupations (7th version, 3-digit codes). The dataset was randomly split into training and test datasets in a ratio of 7:3. The occupation classification model based on DistilKoBERT was fine-tuned using the training dataset, and the model was evaluated using the test dataset. The accuracy, precision, recall, and F1 score were calculated as evaluation metrics. Results: The final model, which classified 28,996 survey participants in the test dataset into 142 occupational codes, exhibited an accuracy of 84.44%. For the evaluation metrics, the precision, recall, and F1 score of the model, calculated by weighting based on the sample size, were 0.83, 0.84, and 0.83, respectively. The model demonstrated high precision in the classification of service and sales workers yet exhibited low precision in the classification of managers. In addition, it displayed high precision in classifying occupations prominently represented in the training dataset. Conclusions: This study developed an occupation classification system based on DistilKoBERT, which demonstrated reasonable performance. Despite further efforts to enhance the classification accuracy, this automated occupation classification model holds promise for advancing epidemiological studies in the fields of occupational safety and health.

Background: This study explored the association between working hours and preventive oral health behaviors. Methods: In total, 48,599 workers (22,992 females) were included from the Korea National Health and Nutrition Examination Survey (2007-2021). Weekly working hours were self-reported. The following three preventive oral health behaviors were set as outcomes: participation in annual dental check-ups; adherence to the recommended toothbrushing frequency (>= twice a day); and use of interdental cleaning devices. We estimated odds ratios (ORs) and 95% confidence intervals (CIs) using logistic regression. Results: In male workers, the adjusted OR (95% CI) of the association between working >= 55 h/week and each outcome was 0.84 (0.77-0.92) for dental check-ups, 0.82 (0.72-0.94) for toothbrushing >= twice a day, and 0.83 (0.76-0.92) for utilization of interdental cleaning device when compared to 35-40 h/week. In female workers, the adjusted OR (95% CI) of the association between working >= 55 h/week and each outcome was 0.79 (0.70-0.89) for dental check-ups, 0.88 (0.70-1.11) for toothbrushing >= twice a day, and 0.80 (0.71-0.90) for utilization of interdental cleaning device when compared to 35-40 h/week. Additionally, low socio-economic status, such as low educational attainment, low income level, and blue-collar occupations, were major risk factors associated with nonadherence to preventive oral health behaviors in both male and female workers. Conclusions: Our study suggests that individuals who work long hours are more likely to exhibit undesirable oral health behaviors.

Poor lifestyle behaviors, including unhealthy dietary habits, lack of physical activity, smoking, inadequate and poor-quality sleep, and alcohol consumption, are well-documented risk factors for health deterioration. Previous studies have suggested that such undesirable lifestyle behaviors may mediate the effects of long working hours on negative health outcomes. This protocol paper aims to introduce and outline the methods for this scoping review. The proposed scoping review will map the existing research on the relationship between working hours and lifestyle behaviors, identifying areas and gaps in the evidence that warrant further investigation. This review will include only peer-reviewed, published articles written in English. All studies examining the relationship or effects of working hours on the five a priori defined major lifestyle components will be considered (diet, physical activity, tobacco use, sleep, and alcohol use), without restrictions on region, publication year, or study design. This review will be performed based on the Preferred Reporting Items for Systematic Reviews and Meta-Analyses extension for Scoping Reviews guidelines. The databases will include MEDLINE, EMBASE, CINAHL, and PsycINFO. The search equation will be structured to include the topic of working hours while also encompassing at least one of the five lifestyle topics: physical activity, diet, sleep, tobacco use, and alcohol consumption. Two reviewers will screen the articles and extract pertinent data. This investigation will primarily focus on evaluating the existing evidence and identifying any gaps in understanding the relationship between working hours and each lifestyle component. A narrative summary will be presented to explain the findings of the included studies.

Background: Social jetlag, the misalignment between biological and social rhythms, can lead to adverse health outcomes. This study explored the association between social jetlag and hazardous alcohol consumption, as well as the sex differences in this association. Methods: This study included a nationally representative sample of Korean workers consisting of 11,462 individuals (5479 women). Social jetlag was calculated as the difference in the mid-point between sleep onset and offset on free days and workdays. Hazardous alcohol consumption was determined using the Alcohol Use Disorder Identification Test-Consumption (range 0-12), with a cutoff of >= 6 for men, >= 5 for women, and >= 3 for those aged >= 65. Logistic regression analysis was used to estimate the odds ratios (ORs) and 95 % confidence intervals (CIs). Results: Among men, 599 out of 5983 individuals (10.0 %) had >= 120 min of social jetlag. Among women, 550 out of 5479 individuals (10.0 %) had >= 120 min of social jetlag. The prevalence of hazardous alcohol use was 56.2 % for men and 27.3 % for women. In the regression analysis, there was a significant sex interaction, where social jetlag >= 120 min was associated with hazardous alcohol consumption in female workers (OR: 1.52, 95 % CI: 1.18-1.96), but not in male workers (OR: 1.04, 95 % CI: 0.84-1.29). Conclusion: High social jetlag was associated with an increased likelihood of hazardous alcohol consumption among women. Our findings underscore the importance of considering sex differences in future research and policy interventions regarding social jetlag and its associated behavior outcomes.

Food insecurity has emerged as a major public health issue. This cross-sectional study explored the association between hazardous alcohol use and food insecurity and how this association varies according to household composition. A nationally representative sample of 31,971 adults from the two separate wave of the Korea National Health and Nutrition Examination Surveys was analyzed. Hazardous alcohol use was measured using the four-item version of the Alcohol Use Disorders Identification Test (AUDIT-4). The outcome variable was food insecurity, as measured using the 18-item Household Food Security Survey. Household composition was classified into three categories: single-person households (individuals living alone), multi-person households without children, and multi-person households with children. Logistic regression was employed to evaluate the association between a 1-standard deviation (SD) increase in AUDIT-4 scores and food insecurity, estimating the odds ratio (OR) and the corresponding 95% confidence interval (CI). Among the participants, 9.4% lived alone, 55.8% lived within multi-person households without children, and 34.8% lived within multi-person households with children. While hazardous alcohol use showed no clear association with food insecurity in the overall sample (OR: 1.01; 95% CI: 0.94-1.08), there was positive interaction between the AUDIT-4 and living alone an on the odds of experiencing food insecurity (P < 0.001). Hazardous alcohol use and a 1-SD increase in AUDIT-4 score were associated with 1.52-fold (95% CI: 1.13-2.05) and 1.22-fold (95% CI: 1.06-1.40) increases in the odds of food insecurity among those living alone. Additionally, consuming ≥10 drinks on a single occasion (OR: 1.93, 95% CI: 1.14-3.26) and experience of concerns by others about drinking (OR: 2.02, 95% CI: 1.28-3.19) were positively associated with food insecurity among those living alone. Hazardous alcohol use is associated with food insecurity, only among individuals living alone. Therefore, targeted policy efforts are necessary to mitigate hazardous alcohol use and food insecurity.

This study explored the association between multidimensional aspects of employment quality and smoking habits. This study included the wage workers in the Korean Labour and Income Panel Study, 2005-2021 (n = 16,188; observations = 92,954). The employment quality was constructed using a multidimensional approach encompassing three dimensions: employment insecurity, income inadequacy, and a lack of rights and protection. The outcome was current smoking in the same year as exposure to employment quality, as well as the incidence of smoking initiation and cessation in the subsequent year. A generalized estimating equation was used for repeated measures analysis to estimate the odds ratio (OR) and 95% confidence intervals (CIs). Compared with those with the highest employment quality, the odds of smoking cessation were lower among those with the low employment quality (OR: 0.81, 95% CI: 0.68-0.95) and those with the lowest employment quality (OR: 0.76, 95% CI: 0.61-0.95). While a comparable relationship was found among males, the correlation in the female sample was unclear. Concurrent smoking status and smoking initiation exhibited no clear associations with overall employment quality in both male and female samples. For individual employment quality indicators, daily employment showed a negative association with the odds of smoking cessation. Therefore, this study suggests that policy interventions aimed at enhancing the employment quality of workers are warranted to reduce smoking rates.

OBJECTIVES: Long working hours and overwork are growing public health concerns in the Western-Pacific region. We explored the relationship between working hours and smoking behaviors of Korean workers. METHODS: This study included 284 782 observations (50 508 workers) from four nationwide cohort studies in Korea. Using generalized estimating equations, we estimated the associations of working hours with current smoking status, smoking initiation, and smoking cessation within each cohort. Cohort-specific estimates were combined through random-effect meta-analysis. Effect sizes were presented as odds ratios (OR) and 95 confidence intervals (CI). RESULTS: The overall smoking prevalence was 26.8% within the cohorts. The adjusted OR (95% CI) of the association between working hours and current smoking were 1.01 (0.94–1.08) for <35 hours/week, 1.04 (1.01–1.09) for 41–48 hours/week, 1.06 (1.01–1.10) for 49–54 hours/week, and 1.07 (1.04–1.10) for ≥55 hours/week compared with 35–40 hours/week. The adjusted OR (95% CI) of the association between working hours and smoking cessation in the follow-up were 0.93 (0.85–1.02) for <35 hours/week, 0.89 (0.83–0.96) for 41–48 hours/week, 0.87 (0.81–0.95) for 48–54 hours/week, and 0.91 (0.85–0.98) for ≥55 hours/week compared with 35–40 hours/week. No clear associations were observed between working hours and smoking initiation. CONCLUSION: Long working hours are associated with high current smoking risk and reduced likelihood of smoking cessation among Korean workers. Policy interventions are required to promote smoking cessation and reduce excess overwork for individuals experiencing long working hours.

Temporary employment is associated with an elevated risk of cardiovascular diseases and mortality. This study explored the association between temporary employment and dietary quality in middle-aged workers. This cross-sectional study included a nationwide sample of middle-aged Korean workers (n = 6467). Employment type was categorized into regular, fixed-term, and daily employment, based on labor contract duration. Dietary quality was assessed using the Korean Health Eating Index (KHEI), which ranges from 0 to 100, with higher scores indicating superior dietary quality. Linear regression was used to estimate beta coefficients (β) and 95% confidence intervals (CI). The survey-weighted proportion of regular, fixed-term, and daily employment was 79.0%, 14.2%, and 6.8%, respectively. Fixed-term and daily employment were associated with a reduced KHEI compared with regular employment (β [95% CI]: −1.07 [−2.11, −0.04] for fixed-term and −2.46 [−3.89, −1.03] for daily employment). In sex-stratified analysis, the association between temporary employment and dietary quality was more pronounced in men (β [95% CI]: −1.69 [−3.71, 0.33] for fixed-term and −2.60 [−4.63, −0.53] for daily employment than in women. In conclusion, this study suggests that temporary employment is a social determinant of dietary quality in middle-aged workers.

Abstract Introduction Precarious employment has been conceptualized as having a multidimensional nature, and research addressing this topic in Asian countries is scarce. This study examined the typologies of multidimensional precarious employment and their relationships with mental health. Methods From October 2020 to April 2021, the Korean Working Conditions Survey was conducted on Korean wageworkers (N=38,347), representative of the nation. With theory-based operationalization of precarious employment, we identified precarious employment typologies through latent class analysis. Logistic regression was performed to explore the association between precarious employment typologies and mental health among workers, represented as odds ratio (ORs) and confidence intervals (CIs). Results Four distinct types of precarious employment emerged: (i) standard employment relationships (SER, 34.5%), (ii) moderate employment precariousness (MEP, 43.5%), (iii) underemployment (17.9%), and (iv) daily laborers (4.1%). Women were overrepresented in the MEP and underemployment types, while the SER type consisted of those with higher educational attainment and white-collar jobs. The OR (95% CI) of depression was 1.38 (1.27–1.50) for the MEP type, 1.48 (1.32–1.66) for the underemployment type, and 2.15 (1.85–2.51) for the daily laborers, compared to the SER type. For individual elements of precarious employment, temporary employment, low wages, low-income predictability, and low involvement in work process were positively associated with depression, whereas part-time employment was negatively associated with depression. Discussion Our findings accord with previous studies that indicated that employment insecurity, inadequate material rewards, and a lack of rights and protection lead to the workers’ poor mental health. Conclusion Policy interventions based on a multidimensional approach are warranted to improve employment quality.

Aims Increasing social concern surrounds the potential adverse health effects of precarious employment (PE). In this study, we explored the association between PE and the onset of depressive symptoms.Methods A total of 11,555 Korean waged workers (5700 females) contributed 62,217 observations from 2009 to 2022. PE was operationalized as a multidimensional construct, including employment insecurity, income inadequacy and lack of rights and protection. Depressive symptoms were evaluated using the Center for Epidemiological Studies-Depression Scale (11-item version). The association between PE and the onset of depressive symptoms in the subsequent year was estimated using generalized estimating equations. Effect sizes were reported as odds ratio (OR) and 95% confidence interval (CI).Results The overall incidence of depressive symptoms was 8.3% during the study period. In cross-sectional analysis, daily employment, disguised employment, lower monthly wages and lack of social insurance coverage were associated with concurrent depressive symptoms in both men and women. Longitudinally, fixed-term employment (OR: 1.17, 95% CI: 1.07-1.29), daily employment (OR: 1.64, 95% CI: 1.45-1.85) and disguised employment (OR: 1.36, 95% CI: 1.17-1.57) were associated with the onset of depressive symptoms among the overall sample. Among men, the lowest quartiles of wage were associated with the onset of depressive symptoms (OR: 1.34, 95% CI: 1.13-1.60), while the absence of a trade union was associated among women (OR: 1.18, 95% CI: 1.01-1.39).Conclusions Employment insecurity, inadequate income and lack of rights and protection may contribute to depressive symptoms. Therefore, PE serves as a significant social determinant of mental health among workers in Korea. Active policy efforts are warranted to improve the overall quality of employment in the workforce.

This study explored the relationship between the Korean Healthy Eating Index (KHEI) and non-alcoholic fatty liver disease (NAFLD). This cross-sectional study included 34,174 Korean adults. The KHEI was composed of three subcomponents (adequacy, moderation, and energy balance) and calculated based on a 24 h dietary recall. The total score ranged from 0 to 100, with a higher score indicating a greater adherence to the Korean dietary guidelines. The total KHEI scores were categorized into quartiles (Q1–Q4). NAFLD was classified using the hepatic steatosis index. Logistic regressions were used to estimate odds ratios (ORs) and 95% confidence intervals (CIs). The adjusted OR (95% CI) of NAFLD was 0.95 (0.87–1.03) for the Q2 group, 0.90 (0.83–0.98) for the Q3 group, and 0.79 (0.72–0.87) for the Q4 group, compared with the Q1 group. Among the subcomponents of the KHEI, individuals with high scores in the adequacy component, characterized by an abundant consumption of fruits, vegetables, and dairy products, exhibited the most pronounced association with NAFLD. A higher KHEI score was negatively associated with NAFLD in Korean adults. Therefore, the promotion of healthy dietary patterns can play a beneficial role in the prevention or management of NAFLD.

BACKGROUND:There has been growing concern about the negative mental health impact of long working hours and overwork. Our study examined how work-life imbalance (WLI) could be a mediator between working hours and poor mental well-being. METHODS:We included 34,968 individuals from a nationwide cross-sectional survey in Korea. Self-reported working hours per week were collected, and mental health was assessed using the World Health Organization (WHO)-5 Well-Being Index. Counterfactual-based mediation models were employed to disentangle the total effects into a direct effect (work hour - poor mental health) and an indirect effect (work hour - WLI - poor mental health). RESULTS:Out of 34,968 participants, 52.6% worked 35-40 hours/week, 20.0% worked 41-48 hours/week, 11.7% worked 49-54 hours/week, and 15.6% worked ≥55 hours/week. The odds ratios (ORs) of the total impact of working hours on poor mental health were 1.08 (95% confidence interval [CI], 1.01-1.16) for 41-48 hours/week, 1.28 (95% CI, 1.17-1.39) for 49-54 hours/week, and 1.60 (95% CI, 1.48-1.74) for ≥55 hours/week in comparison to 35-40 hours/week. The ORs of the indirect effects were 1.04 (95% CI, 1.03-1.05) for 41-48 hours/week, 1.08 (95% CI, 1.07-1.09) for 49-54 hours/week, and 1.14 (95% CI, 1.12-1.16) for ≥55 hours/week, accounting for 51%, 31%, and 28% of the total effects, respectively. CONCLUSION:Our findings suggest that WLI can partially mediate the association of long working hours with mental health deterioration. Policy efforts are required to mitigate the adverse mental health effects of overwork.

This study aimed to reveal the relationship of the days of experiencing sickness presentism and depressive symptoms among Korean workers. Sickness presenteeism which defined as the act of going to work despite being feeling unhealthy triggers various adverse effects on mental health, including increased risks of depression. Furthermore, Sickness presenteeism is a major social issue causing substantial socioeconomic costs. The data of 25120 participants from sixth Korean Working Condition Survey was utilized in this cross-sectional study. Sickness presenteeism was defined using a self-reported questionnaire and depressive symptoms were assessed by WHO well-being index. Multivariate logistic regression analysis was conducted to calculate the odd ratios for depressive symptoms regarding the number of days experiencing sickness presenteeism. We calculated odds ratios (ORs) and 95

Objectives: Social jetlag (SJL), which is characterised by a misalignment between biological and social time, is associated with cardiometabolic risk factors. This study investigated the relationship between SJL, leisure-time physical activity (LTPA) and muscle strengthening exercise (MSE) in young adults. Study design: This was a cross-sectional study. Methods: This cross-sectional study included a nationally representative sample of young adults aged 19-29 years (n = 2113). SJL was calculated as the difference in the midpoint of sleep onset and offset time between weekdays and weekends. The dependent variables were engagement in >= 150 min/week of moderate-to-vigorous LTPA and engagement in MSE >= 2 days/week based on guidelines provided by the World Health Organisation. Logistic regression analysis was performed to estimate odds ratios (ORs) and 95% confidence intervals (CIs). Non-linear relationships were estimated using restricted cubic spline regression. Results: The study population comprised 975 men and 1138 women. Among participants, 4.6% had <0 min, 41.9% had 0-59 min, 25.7% had 60-119 min and 27.7% had >= 120 min SJL. Those with >= 120 min SJL had a reduced likelihood of achieving the recommended level of LTPA (OR: 0.71, 95% CI: 0.52-0.95) and MSE (OR: 0.73, 95% CI: 0.55-0.97). In the non-linear model, an inverse U-shaped association was observed, wherein the highest probability of meeting the recommended level of LTPA and MSE was observed in those with 45 min SJL, decreasing after this threshold. Conclusions: Individuals with >= 120 min SJL were less likely to engage in the recommended level of both aerobic and anaerobic exercise. Although future studies using a longitudinal design are required to elucidate the causal relationship between SJL and physical activity, the current findings suggest that physical inactivity during leisure time may play an important role in the increased risk of cardiometabolic abnormalities in young adults with SJL. (c) 2024 The Royal Society for Public Health. Published by Elsevier Ltd. All rights are reserved, including those for text and data mining, AI training, and similar technologies.

Existing evidence suggests that exposure to ambient particulate matter (PM) causes various adverse health outcomes through systemic inflammation. We explored the association between PM exposure and high- sensitivity C-reactive protein (hs-CRP) levels in a Korean population. This cross-sectional study included a representative sample of 21,154 Korean individuals, linked to modeled air quality data from 2015 to 2018. Concentrations of PM10 and PM 2.5 were estimated for 1-week (short-term), 2-month, 4-month, 6-month (medium-term), and 1-year (long-term) moving averages before the survey date for each participant. The association between log-transformed hs-CRP levels and PM exposure was assessed using linear regression. The effect sizes were expressed as percent changes with 95% confidence intervals (CIs). The percent change (95% CI) in hs-CRP levels per a 10-mu m/m3 increase in PM10, according to moving averages, was 0.47 (-1.13, 2.10) for 1-week, 4.87 (2.50, 7.29) for 2-month, 8.21 (4.89, 11.64) for 4-month, 11.26 (6.81, 15.89) for 6-month, and 7.15 (2.54, 11.98) for 1-year. The percent change (95% CI) in hs-CRP levels per a 10-mu m/m3 increase in PM2.5, according to moving averages, was 0.66 (-2.38, 3.79) for 1-week, 7.51 (2.86, 12.36) for 2-month, 14.26 (8.23, 20.62) for 4-month, 20.29 (12.42, 28.70) for 6-month, and 17.76 (8.51, 27.79) for 1-year. The relationship between PM exposure and hs-CRP levels remained independent even after adjusting for sociodemographic characteristics and other co- pollutants. Exposure to PM10 and PM2.5, particularly over longer periods, showed positive association with hsCRP levels in Korean adults. These findings highlight the necessity for policy efforts aimed at enhancing air quality and mitigating the health impacts of PM exposure.