Liver Cancer Risk Across Metabolic Dysfunction-Associated Steatotic Liver Disease and/or Alcohol: A Nationwide Study.

INTRODUCTION: New terminologies of metabolic dysfunction-associated steatotic liver disease (MASLD) have been developed. We assessed hepatocellular carcinoma (HCC) risk across MASLD and/or alcohol intake. METHODS: We included participants aged 40-79 years receiving a national health checkup from 2009 to 2010 in the Republic of Korea, classified as follows: non-MASLD, MASLD, MASLD with increased alcohol intake (MetALD; weekly alcohol 210-420 g for male and 140-350 g for female individuals), and alcohol-associated liver disease (ALD; excessive alcohol intake with weekly alcohol ≥420 g for male or ≥350 g for female individuals). The primary outcome was HCC incidence. HCC risk was estimated using multivariable Cox proportional hazard models. RESULTS: Among 6,412,209 participants, proportions of non-MASLD, MASLD, MetALD, and ALD cases were 59.5%, 32.4%, 4.8%, and 3.4%, respectively. During follow-up (median 13.3 years), 27,118 had newly developed HCC. Compared with non-MASLD, the HCC risk increased from MASLD (adjusted hazard ratio [aHR] 1.66, 95% confidence interval [CI] 1.62-1.71) and MetALD (aHR 2.17, 95% CI 2.08-2.27) to ALD (aHR 2.34, 95% CI 2.24-2.45) in a stepwise manner. Furthermore, the older and non-cirrhosis subgroups were more vulnerable to detrimental effects of MASLD and/or alcohol intake, concerning HCC risk. Among the older, female, and cirrhosis subgroups, MetALD poses similar HCC risks as ALD. DISCUSSION: HCC risk increased from MASLD and MetALD to ALD in a stepwise manner, compared with non-MASLD. For an effective primary prevention of HCC, a comprehensive approach should be required to modify both metabolic dysfunction and alcohol intake habit.

Effect of long working hours on psychological distress among young workers in different types of occupation.

BACKGROUND: We investigated how the association between long working hours and psychological distress varies across different employment and occupation types in young workers. METHODS: Examining a nationally representative sample of 7246 Korean workers (3621 women) aged 15 to 40, we analyzed 23,492 observations spanning from 2016 to 2020. Psychological distress was measured using the Brief Encounter Psychosocial Instrument. We employed a generalized estimating equation to estimate odds ratios (ORs) and 95% confidence intervals (CIs). RESULTS: Of the total observations, 5.2% worked <35 h/week, 52.9% worked 35-40 h/week, 23.5% worked 41-48 h/week, 10.3% worked 49-54 h/week, and 8.2% worked ≥55 h/week. The OR (95% CI) of the association between long working hours and psychological distress was 1.38 (1.11-1.72) for <35 h/week, 1.47 (1.32-1.65) for 41-48 h/week, 1.74 (1.49-2.04) for 49-54 h/week, and 2.11 (1.75-2.55) for ≥55 h/week compared to 35-40 h/week. The OR (95% CI) of the association between working ≥55 h/week and psychological distress was significantly higher among wage workers (OR [95% CI]: 2.37 [1.94-2.89]) compared to self-employed workers (OR [95% CI]: 0.84 [0.52-1.36]). Additionally, the OR (95% CI) of the association between working ≥55 h/week and psychological distress was significantly higher among white-collar workers (OR [95% CI]: 3.24 [2.54-4.13]) compared to service/sales workers (OR [95% CI]: 1.22 [0.86-1.72]) or blue-collar workers (OR [95% CI]: 1.71 [1.10-2.67]). No clear gender differences were observed. CONCLUSION: Psychological distress caused by long working hours can be pronounced among white-collar and wage workers.

Association between long working hours and engagement in preventive healthcare services in Korean workers: Findings from the Korean National Health and Nutrition Examination Survey.

BACKGROUND: Engagement in preventive healthcare services is crucial for preventing diseases. We explored how working hours are associated with engagement in preventive healthcare services, with a focus on gender differences. METHODS: This cross-sectional study used data from the 2007-2012 Korean National Health and Nutrition Examination Survey. The dependent variable was engagement in each of the five preventive healthcare services (health check-ups, influenza vaccination, and stomach, breast, and cervical cancer screenings). We estimated the prevalence ratios (PRs) and 95% confidence intervals (CIs) using robust Poisson regression. RESULTS: The study analyzed 19,819 workers (9119 women). The adjusted PRs (95% CI) of the association between working ≥55 h per week and engagement in preventive healthcare services among men were 0.95 (0.90-1.00) for health check-ups, 0.86 (0.77-0.96) for influenza vaccination, and 0.95 (0.87-1.03) for stomach cancer screening compared to working 35-40 h per week. Among women, the adjusted PRs (95% CI) of the association between working ≥55 h per week and engagement in preventive healthcare services were 0.84 (0.78-0.91) for health check-ups, 0.82 (0.73-0.92) for influenza vaccination, and 0.88 (0.80-0.97) for stomach, 0.85 (0.78-0.94) for breast, and 0.82 (0.74-0.91) for cervical cancer screenings. CONCLUSION: Long working hours were negatively associated with engagement in preventive healthcare services, and the association was pronounced among female workers. Efforts to promote preventive healthcare participation among individuals with long working hours are necessary, and it is essential to consider the unique vulnerabilities of women when developing such policies.

Association between long working hours and diet quality and patterns: A latent profile analysis of a nationally representative sample of Korean workers.

BACKGROUND: Long working hours are associated with cardiovascular and metabolic diseases. This study investigated the relationship between the working hours and dietary qualities and patterns in Korean workers. METHODS: Data from 24,523 workers were extracted from the Korea National Health and Nutrition Examination Survey, 2013-2021. The Korean Healthy Eating Index (KHEI), which ranges from 0 to 100, with a higher score indicating greater adherence to Korean dietary guidelines and superior dietary quality, was used for dietary assessment. We identified dietary patterns and classified workers using latent profile analysis. Logistic regressions were used to estimate odds ratios (ORs) and 95% confidence intervals (CIs). RESULTS: Five distinct dietary patterns emerged: healthy diet (24.8%), low-vegetable diet (14.0%), average diet (7.8%), low-fruit diet (31.4%), and poor diet (22.0%). The mean KHEI score was 60.8, with the highest score observed in the healthy diet pattern (71.3) and the lowest, in the poor diet pattern (50.0). Compared with working 35-40 h/week, working ≥55 h/week was negatively associated with KHEI scores (ß: -1.08; 95% CI: -1.67, -0.49). Those working ≥55 h/week were less likely to have a healthy diet pattern (OR: 0.81; 95% CI: 0.72, 0.91) and more likely to have a low-fruit diet (OR: 1.36; 95% CI: 1.20, 1.55) or poor diet pattern (OR: 1.23; 95% CI: 1.05, 1.43) compared with those working 35-40 h/week. CONCLUSION: Long working hours are associated with undesirable dietary quality and patterns. Policy interventions aimed at enhancing dietary quality are needed to alleviate the health burdens associated with long working hours.

Long working hours, work-life imbalance, and poor mental health: a cross-sectional mediation analysis based on the sixth Korean Working Conditions Survey, 2020-2021.

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 was collected, and mental health was assessed by the 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 h/week, 20.0% worked 41-48 h/week, 11.7% worked 49-54 h/week, and 15.6% worked ≥55 h/week. The odds ratios (ORs) of the total impact of working hours on poor mental health were 1.08 (95% CI: 1.01-1.16) for 41-48 h/week, 1.28 (1.17-1.39) for 49-54 h/week, and 1.60 (1.48-1.74) for ≥55 h/week in comparison to 35-40 h/week. The ORs of the indirect effects were 1.04 (1.03-1.05) for 41-48 h/week, 1.08 (1.07-1.09) for 49-54 h/week, and 1.14 (1.12-1.16) for ≥55 h/week, accounting for 51%, 31%, and 28% of the total effects.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.

Association between temporary employment and current smoking and change in smoking behaviors: A prospective cohort study from South Korea (2009-2018).

Background Previous studies have suggested that employment insecurity is associated with adverse health outcomes. We explored the association between temporary employment and smoking behaviors.Methods We analyzed 11,795 workers (51,867 observations) from the Korea Health Panel Study (2009-2018). Employment types were categorized as regular, fixed-term, or daily, based on the duration of labor contract. The outcomes were current smoking status and changes in smoking behavior (initiation or cessation) in the following year. Generalized estimating equations were used to estimate odds ratio (OR) and 95% confidence interval (CI).Results The proportions of fixed-term and daily workers were 41.2% and 16.4% for women and 23.6% and 12.4% for men, respectively. Temporary employment was associated with increased odds of current smoking, while also demonstrating prospective associations with changes in smoking behaviors. For instance, in prospective analyses, male workers with fixed-term and daily employments were associated with a decreased likelihood of smoking cessation (OR:0.77; 95% CI:0.65-0.91 for fixed-term employment and OR:0.66; 95% CI:0.52-0.83 for daily employment) in the following year compared to those with regular employment. Moreover, those experiencing consecutive temporary employment was most inversely associated with smoking cessation in both men (OR:0.56; 95% CI:0.44-0.71) and women (OR:0.37; 95% CI:0.16-0.85) compared to those experiencing consecutive regular employment. However, no clear association between temporary employment and smoking initiation was observed in both men and women.Conclusions Temporary employment is directly associated with current smoking and inversely associated with smoking cessation. Policies are needed to improve job insecurity among temporary employees.

Job dissatisfaction as a risk factor of depressive symptoms and suicidal ideation among female workers: evidence from a nationwide longitudinal study in South Korea.

This study aimed to investigate the relationship between job dissatisfaction (JD) and depressive symptoms and suicidal ideation among female workers. Additionally, it examined how the cumulative exposure to JD over multiple years can exacerbate the effect. We conducted our analyses on a nationwide sample of 6111 female workers from the Korean Longitudinal Survey of Women and Family (Waves 5-7). Depressive symptoms were measured using the 10-item version of the Centre for Epidemiologic Studies Depression Scale. JD was classified into quartiles (Q1-Q4), and odds ratios (ORs) with 95% confidence intervals (CIs) were calculated using generalised estimating equations. The overall prevalence of depressive symptoms and suicidal ideation among study participants was 13.9% and 2.4%, respectively. Our findings revealed that female workers with the highest level of JD (Q4) had a significantly greater risk of depressive symptoms (OR [95% CI]: 1.61 [1.37-1.89]) and suicidal ideation (OR [95% CI]: 2.08 [1.37-3.17]) after 2-year follow-up compared to those with the lowest level of JD (Q1). Consecutive exposure to JD over multiple years was also associated with depressive symptoms and suicidal ideation after a 2-year follow-up. For instance, women exposed to JD for three consecutive waves exhibited a high risk of depressive symptoms (OR [95% CI]: 1.61 [1.33-1.95]) and suicidal ideation (OR [95% CI]: 1.67 [1.04-2.70]). JD was positively associated with depressive symptoms and suicidal ideation. Our study suggests that JD is a risk factor for mental health problems in female workers.

Association between sickness presenteeism and depressive symptoms: a cross-sectional study using the 6th Korean working conditions survey.

PURPOSE: 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. METHODS: 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% confidence interval (95% CI) for depressive symptoms after categorizing participants into three groups based on the duration of experiencing sickness presenteeism, using cut-off values of 3 and 5 days. RESULTS: Workers who have experienced sickness presenteeism for more than 5 days were at highest risk for depressive symptoms than referent group (OR 2.87; 95% CI 2.17-3.76 in male, OR 3.86; 95% CI 3.02-4.91 in female). Furthermore, there was a trend of increasing risk for depressive symptom as the duration of experiencing sickness presenteeism extended. CONCLUSION: This study presents the association between experiencing sickness presenteeism in the previous 12 months and depressive symptoms. Based on the results, we provide individual and organizational strategies of reducing sickness presenteeism. Also, screening for workers who have experienced sickness presenteeism are needed to ensure good mental health.

Association between constant connectivity to work during leisure time and insomnia: does work engagement matter?

PURPOSE: The influx of communication media to contemporary workplaces has exposed workers to be always connected to their work. Constant connectivity to work (CCW) refers to the condition in which workers are always connected to work, even during their non-work hours, and are not detached from the work situation. We investigated the association between CCW and insomnia and the moderating effect of work engagement. METHODS: A total of 29,512 nationally representative samples of workers in Korea were used. Insomnia was assessed by the Minimal Insomnia Symptom Scale. Logistic regression was used to estimate odds ratios (ORs) and 95% confidence intervals (CIs). The additive interaction between CCW and low work engagement was estimated by calculating Relative Excess Risk due to Interaction (RERI). RESULTS: Exposure to CCW was related to insomnia (OR [95% CI] 1.33 [1.22-1.46]). Additionally, a significant negative interaction between CCW and work engagement was observed. The effects of CCW were mitigated in those with high work engagement. The OR of the combined effect of CCW exposure and low work engagement was 2.52 (95% CI 2.22-2.87). RERI between exposure to CCW and low work engagement was 0.69 (95% CI 0.38-0.99), indicating that there is a supra-additive interaction. CONCLUSION: Our study found that CCW is related to an increased risk of insomnia and that high work engagement can mitigate the effect of CCW. Our study suggests that improving work engagement and disconnecting from work outside of work hours can help protect employees' sleep quality.

Comparable Mortality Between Asian Patients with Chronic Hepatitis B Under Long-Term Antiviral Therapy vs Matched Control: A Population-Based Study.

INTRODUCTION: Antiviral therapy (AVT) substantially improved the prognosis for patients with chronic hepatitis B (CHB). Head-to-head comparisons of prognosis between treated patients with CHB and the general population are scarce. We directly compared the prognosis between Asian patients with CHB receiving AVT and the general population. METHODS: From the South Korean National Health Insurance Service database, patients with CHB receiving AVT ≥3 years, aged 40-64 years, who underwent health examinations between 2011 and 2012 (AVT-CHB group) were recruited. As a control, propensity score-matched general population was chosen among patients without CHB. The primary outcome was all-cause mortality; secondary outcomes were cardiovascular disease (CVD), hepatocellular carcinoma (HCC), and all types of non-HCC malignancies. RESULTS: During follow-up (median 7.2 years), 26,467 and 75,469 individuals in the AVT-CHB group and matched general population were analyzed. The 5- and 7-year cumulative all-cause mortality rates were 0.40% and 1.0% for the AVT-CHB group vs 0.50% and 1.0% for the matched general population (adjusted hazard ratio [aHR] 0.96, 95% confidence interval [CI] 0.83-1.10; P = 0.51). The AVT-CHB group had a lower risk of CVD than the matched general population (aHR 0.70, 95% CI: 0.62-0.79; P < 0.001). Although the AVT-CHB group was more likely to develop HCC than the matched general population (aHR 13.16, 95% CI: 10.90-15.89; P < 0.001), the non-HCC malignancy risks in the AVT-CHB group were comparable to the matched general population (aHR 1.05, 95% CI 0.98-1.13; P = 0.137). DISCUSSION: The AVT-CHB group had a similar risk of all-cause mortality and non-HCC malignancies and a lower risk of CVD than the matched general population.

Statin use is associated with better post-operative prognosis among patients with hepatitis B virus-related hepatocellular carcinoma.

BACKGROUND: The high postoperative recurrence rate of hepatocellular carcinoma (HCC) is a significant challenge. Patient metabolic factors are potential disease modifiers and should be examined as risk factors for postoperative prognosis. Here, we assessed the association between long-term statin use and HCC recurrence after surgical resection of hepatitis B virus (HBV)-related HCC. METHODS: Patients who initially underwent curative resection for HBV-related HCC between 2005 and 2015 were recruited and followed up until December 2019. Patients were classified into statin user and non-statin user groups based on whether or not they had been prescribed statins for ≥2 years. The primary outcome was HCC recurrence, and the secondary outcome was liver-related mortality. The cumulative incidence by statin use was estimated using the Kaplan-Meier method and compared using the log-rank test. Adjusted hazard ratios (HRs) and 95% confidence intervals (CIs) were estimated using multivariable Cox regression. RESULTS: Among 5653 patients with a median 6.1 years of follow-up, HCC recurrence and liver-related mortality occurred in 1603 and 316 patients, respectively. The 5-year cumulative incidence of HCC recurrence in the statin user group (15.9%) was significantly lower than that in the non-user group (21.3%; p = .019). From multivariable Cox regression analysis, statin use was significantly associated with a reduced risk of HCC recurrence (aHR 0.77, 95% CI: 0.61-0.98; p = .035) and liver-related mortality (aHR 0.48, 95% CI: 0.25-0.90; p = .023). CONCLUSION: Long-term statin use was significantly associated with reduced risk of HCC recurrence and liver-related mortality after curative resection of HBV-related HCC.

Association between long working hours and cigarette smoking, leisure-time physical activity, and risky alcohol use: Findings from the Korea National Health and Nutrition Examination Survey (2014-2021).

BACKGROUND: Long working hours cause adverse health outcomes; however, the precise mechanisms underlying this relationship remain unknown. We examined the association between long working hours and health behaviors, as well as gender differences in this association. METHODS: A nationally representative sample of 26,385 Korean workers was analyzed. The exposure variable was self-reported weekly working hours. The outcomes examined were cigarette smoking, high-level physical activity (defined as engaging in ≥150 min/week of moderate-to-vigorous leisure-time physical activity), and risky alcohol use (defined as consuming seven glasses for men or five glasses for women of alcohol in a single sitting, twice or more per week). Logistic regression models were utilized, and gender differences were examined by incorporating interaction terms into the regression models. RESULTS: Among 26,385 workers, 4,109 (16%) worked ≥55 h/week. The prevalence of cigarette smoking, high-level physical activity, and risky alcohol use was 19%, 18%, and 14%, respectively. The odds ratio (OR) (95% confidence interval [CI]) of the association between working ≥55 h/week and outcomes was 1.26 (1.12-1.43) for cigarette smoking, 0.73 (0.65-0.83) for high-level physical activity, and 0.95 (0.83-1.08) for risky alcohol use compared to working 35-40 h/week. A moderating effect of gender on the association between long working hours and risky alcohol use was observed. The OR (95% CI) of the association between working ≥55 h/week was 0.88 (0.76-1.02) in men and 1.51 (1.12-2.05) in women. CONCLUSION: Our findings emphasize the need for policy interventions aimed at reducing excessive working hours and fostering healthy lifestyle behaviors among individuals engaged in long working hours.

Associations between precarious employment and smoking and regular exercise: Results from a Korean longitudinal panel study from 2005 to 2020.

We examined whether precarious employment (PE) is related to cigarette smoking and physical inactivity and whether a longer duration of PE intensifies the detrimental impact. Using Korean longitudinal panel data, 89,289 observations of 15,712 employees were analyzed. Mixed models were applied to estimate the odds ratio (OR) and 95% confidence intervals (CIs). We adjusted for time-varying characteristics of the participants (age, education, marital status, income, occupation, and working hours). ORs of associations between PE and current smoking were 1.09 (95% CI: 0.95-1.25) in men and 1.77 (1.03-3.05) in women. Also, ORs of associations between PE and regular exercise were 0.52 (0.46-0.58) in men and 0.95 (0.85-1.07) in women. Next, the longer the duration of PE was related to the higher the risk of current smoking and physical inactivity. For instance, over 6 years of PE was related to the highest risk of current smoking in men (1.80 [1.38-2.34]) and women (3.94 [1.25-12.44]). Also, over 6 years of PE was related to the lowest likelihood of regular exercise in men (0.47 [0.37-0.59]), but not in women (0.83 [0.65-1.06]). A longer duration of PE is also related to a change in health behaviors among men. Over 6 years of PE was associated with the highest risk of smoking initiation (2.02 [1.28-3.19]) and the lowest likelihood of exercise initiation (0.42 [0.32-0.55]) in men. However, a longer duration of PE was not associated with a change in health behaviors in women. Our findings highlight that PE have a detrimental impact on health behaviors.

Multidimensional typologies of precarious employment and their relationships with mental well-being in Korean wageworkers: A latent class analysis based on the Korean Working Conditions Survey (2020-2021).

BACKGROUND: Precarious employment (PE) has been conceptualized as having a multidimensional nature, and research addressing this topic in Asian countries is scarce. This study examined the typologies of PE and their relationships with mental health among Korean workers. METHODS: From October 2020 to April 2021, the Korean Working Conditions Survey was conducted on Korean wageworkers (weighted N = 38,347), representative of the nation. With theory-based operationalization of PE, we identified typologies and classified workers through latent class analysis. Logistic regression was performed to explore the association between PE typologies and mental health among workers, represented as odds ratio (ORs) and confidence intervals (CIs). RESULTS: Four distinct employment typologies 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 PE, 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. CONCLUSION: Employment insecurity, low material rewards, and a lack of rights and protection can contribute to the poor mental health of workers. Policy interventions are warranted to mitigate inequalities in employment quality among Korean workers.

Self-Esteem Trajectories After Occupational Injuries and Diseases and Their Relation to Changes in Subjective Health: Result From the Panel Study of Workers' Compensation Insurance (PSWCI).

BACKGROUND: Occupational injuries and diseases are life events that significantly impact an individuals' identity. In this study, we examined the trajectories of self-esteem among victims of occupational injury and disease and their relation to health. METHODS: The Panel Study of Workers' Compensation Insurance conducted annual follow-ups on workers who had experienced occupational injury or disease. A total of 2,000 participants, who had completed medical care, were followed from 2013 to 2017. Growth mixture modeling was utilized to identify latent classes in the self-esteem trajectory. Additionally, logistic regressions were conducted to explore the association between trajectory membership, baseline predictors, and outcomes. RESULTS: Three distinct trajectory classes were identified. Total 65.8% of the samples (n = 1,316) followed an increasing self-esteem trajectory, while 31.1% (n = 623) exhibited a constant trajectory, and 3.1% (n = 61) showed a decreasing trajectory. Individuals with an increasing trajectory were more likely to have a higher educational attainment (odds ratio [OR], 1.86; 95% confidence interval [CI], 1.20-2.88), an absence of a moderate-to-severe disability rating (OR, 0.49; 95% CI, 0.25-0.96), no difficulty in daily living activities (OR, 0.81; 95% CI, 0.75-0.88), and were economically active (re-employed: OR, 2.46; 95% CI, 1.52-3.98; returned to original work: OR, 4.46; 9% CI, 2.65-7.50). Those with a decreasing self-esteem trajectory exhibited an increased risk of poor subjective health (OR, 1.89; 95% CI, 0.85-4.85 in 2013 to OR, 3.17; 95% CI, 1.04-13.81 in 2017), whereas individuals with an increasing trajectory showed a decreased risk (OR, 0.54; 95% CI, 0.43-0.68 in 2013 to OR, 0.44; 95% CI, 0.33-0.57 in 2017). CONCLUSION: Our findings emphasize the diversity of psychological responses to occupational injury or disease. Policymakers should implement interventions to enhance the self-esteem of victims.

Socioeconomic Disparities in the Association Between All-Cause Mortality and Health Check-Up Participation Among Healthy Middle-Aged Workers: A Nationwide Study.

BACKGROUND: This study assessed the relationship between non-participation in health check-ups and all-cause mortality and morbidity, considering socioeconomic status. METHODS: Healthy, middle-aged (35-54 years) working individuals who maintained either self-employed or employee status from 2006-2010 were recruited in this retrospective cohort study from the National Health Insurance Service in Korea. Health check-up participation was calculated as the sum of the number of health check-ups in 2007-2008 and 2009-2010. Adjusted hazard ratio (HR) and 95% confidence interval (CI) of all-cause mortality were estimated for each gender using multivariable Cox proportional hazard models, adjusting for age, income, residential area, and employment status. Interaction of non-participation in health check-ups and employment status on the risk of all-cause mortality was further analyzed. RESULTS: Among 4,267,243 individuals with a median 12-year follow-up (median age, 44; men, 74.43%), 89,030 (2.09%) died. The proportion (number) of deaths of individuals with no, one-time, and two-time participation in health check-ups was 3.53% (n = 47,496), 1.66% (n = 13,835), and 1.33% (n = 27,699), respectively. The association between health check-up participation and all-cause mortality showed a reverse J-shaped curve with the highest adjusted HR (95% CI) of 1.575 (1.541-1.611) and 1.718 (1.628-1.813) for men and women who did not attend any health check-ups, respectively. According to the interaction analysis, both genders showed significant additive and multiplicative interaction, with more pronounced additive interaction among women who did not attend health check-ups (relative excess risk due to interaction, 1.014 [0.871-1.158]). CONCLUSION: Our study highlights the significant reverse J-shaped association between health check-up participation and all-cause mortality. A pronounced association was found among self-employed individuals, regardless of gender.

Clinical Indication of Aspirin Associated With Reduced Risk of Liver Cancer in Chronic Hepatitis B: A Nationwide Cohort Study.

INTRODUCTION: Despite the overall association of aspirin on reduced hepatocellular carcinoma (HCC) risk, there have been few studies on its benefit according to specific clinical conditions among hepatitis B virus (HBV)-infected patients. This study aimed to identify subgroups which benefit from long-term aspirin use. METHODS: Nationwide data covering the HBV-infected population in the Republic of Korea from 2010 to 2011 were analyzed. Patients who had been taking Aspirin for ≥3 years were classified as aspirin users. The primary outcome was HCC development. The multivariable Fine and Gray competing risk regression model was used to estimate the adjusted hazard ratio (HR) in the entire cohort. Propensity score matching at a 1:4 ratio was also performed. RESULTS: Among 161,673 patients, 7,083 newly developed HCC during follow-up (mean: 7.5 years). After adjusting for age, sex, hypertension, diabetes mellitus, dyslipidemia, cirrhosis, antivirals, metformin, statin, smoking, alcohol consumption, and obesity, aspirin users (n = 9,837) were less likely to develop HCC; the adjusted HR was 0.84 (P = 0.002) in the entire cohort and 0.87 (P = 0.010) in the matched cohort. Association of aspirin use with all-cause mortality was not significant (HR = 0.93; P = 0.192), whereas association with liver-related mortality was significant (HR = 0.79; P = 0.019). A significant association was observed in the subgroups with cirrhosis, both sexes, hypertension, non-diabetes mellitus, nonantivirals against chronic hepatitis B, nonmetformin use, nonstatin use, both smoking histories, and obesity (all P < 0.05). DISCUSSION: Long-term aspirin use is significantly associated with reduced risk of HCC in chronic HBV patients. More comprehensive studies should be implemented to clarify the causal relationship.

The relationship between occupational dust exposure and incidence of diabetes in male workers: A retrospective cohort study.

AIM: Previous studies have focused on the association between ambient particulate matter and diabetes. However, the relationship between subacute exposure to occupational dust and diabetes has not been explored. We aimed to assess this relationship. METHODS: Men who worked in dust-related process factories between January 2013 and December 2017 were recruited from a Korea Health Worker Examination Common Data Model cohort. A history of physician-diagnosed diabetes, use of an anti-diabetic drug, or a fasting blood glucose level of ≥7 mmol/L were considered the criteria to diagnose diabetes. Multivariable time-dependent Cox analysis estimated hazard ratios (HRs) and 95% CIs for incident diabetes associated with exposure to occupational dust exposure; interactions with lifestyle factors were analysed. Sensitivity analyses used propensity score matching and landmark analysis. RESULTS: Among 5141 male participants (median follow-up duration, 3.85 years), 349 participants had diabetes. Occupational dust exposure was related to an increased risk of diabetes in the time-dependent Cox analysis (entire cohort: HR 1.66 [95% CI 1.25-2.19], matched cohort: HR 1.65 [95% CI 1.22-2.24]). The findings showed the same direction in the landmark analysis (HR 1.42 [95% CI 1.01-1.99]). CONCLUSIONS: A significant relationship exists between occupational dust exposure and increased risk of diabetes in male workers. Further studies should be conducted to confirm that occupational dust exposure is a possible risk factor for diabetes.

Effect of metabolic dysfunction-associated fatty liver disease on liver cancer risk in a population with chronic hepatitis B virus infection: A nationwide study.

BACKGROUND: The association between metabolic dysfunction-associated fatty liver disease (MAFLD) and hepatocellular carcinoma (HCC) lacks clinical validation in at-risk populations. We assessed this relationship among chronic hepatitis B (CHB) patients. METHODS: Data was collected from the National Health Insurance System database in South Korea. Chronic hepatitis B patients aged over 40 years receiving health examinations between 2011 and 2012 were recruited. The primary outcome was HCC. Metabolic dysfunction-associated fatty liver disease was defined as hepatic steatosis in combination with at least one of the following: (i) overweight, (ii) diabetes, or (iii) lean/normal weight with two or more metabolic components. Multivariable Cox regression analysis was used to estimate adjusted hazard ratios (aHRs). RESULTS: Of 197 346 participants, 66 149 had MAFLD; 19 149, 44 475, and 2525 fulfilled diabetes (regardless of overweight), overweight alone, and lean/normal weight with two or more metabolic components, respectively. During follow-up (median 7 years), 13 771 developed HCC. Metabolic dysfunction-associated fatty liver disease was independently associated with increased risk of HCC, with aHR of 1.36 (p < 0.001). Propensity score matching confirmed the same phenomena, with aHR of 1.37 (p < 0.001). Furthermore, when stratified by liver cirrhosis and/or antiviral therapy, independent significances of MAFLD for HCC risk were maintained (all p < 0.001). Compared with the persistent non-MAFLD subgroup during the entire follow-up, diagnosis of MAFLD from at least one health examination significantly increased HCC risk with aHRs of 1.41, 1.37, and 1.14 among subgroups with persistent MAFLD, MAFLD to non-MAFLD, and non-MAFLD to MAFLD, respectively (all p < 0.05). CONCLUSIONS: Metabolic dysfunction-associated fatty liver disease consistently increases HCC risk among CHB patients. Further studies are needed to develop an effective preventive strategy through control of metabolic health.

Synthetic Peucedanocoumarin IV Prevents α-Synuclein Neurotoxicity in an Animal Model of Parkinson's Disease.

Pathological protein inclusion formation and propagation are the main causes of neuronal dysfunction in diverse neurodegenerative diseases; therefore, current disease-modifying therapeutic strategies have targeted this disease protein aggregation process. Recently, we reported that peucedanocoumarin III (PCiii) is a promising therapeutic compound with the ability to disaggregate α-synuclein inclusion and protect dopaminergic neurons in Parkinson's disease (PD). Here, we found that trans-4'-acetyl-3'-tigloylkhellactone (racemic peucedanocoumarin IV [PCiv]), a structural isomer of PCiii with a higher synthetic yield presented a strong anti-aggregate activity to a degree comparable to that of PCiii. PCiv retained effective inhibitory function against ß-sheet aggregate-mimic ß23 cytotoxicities and potently prevented α-synucleinopathy in α-synuclein preformed fibril (PFF)-treated mice cortical neurons. In detailed pharmacokinetic profiling of PCiv, oral administration of PCiv in rats exhibited an approximately 97-min half-life and 10% bioavailability. Moreover, tissue distribution analysis revealed favorable profiles of brain penetration with a 6.4 brain-to-plasma concentration ratio. The therapeutic efficacy of PCiv was further evaluated in a sporadic PD mouse model with a combinatorial co-injection of α-synuclein preformed fibril and recombinant adeno-associated virus expressing α-synuclein. Motor dysfunctions induced in this combinatorial α-synucleinopathy PD mouse model was almost completely rescued by PCiv diet administration, and this therapeutic effect is consistent with the marked prevention of dopaminergic neuron loss and suppression of α-synuclein aggregation. Taken together, our translational study suggests that PCiv is advantageous as a therapeutic agent for neurodegenerative diseases, especially with its good synthetic yield, high brain distribution, and anti-aggregate activity. PCiv may be useful in the management of α-synuclein inclusion formation and propagation at different stages of PD.