Ethnic discrimination, asking for fair treatment, and poor self-rated health: a gender stratified analysis of 13,443 Korean Chinese waged workers in South Korea.

BACKGROUND: In South Korea, Korean Chinese workers experience ethnic discrimination although they share physical similarities and ethnic heritage with native-born Koreans. This study aimed to examine whether perceived ethnic discrimination is associated with poor self-rated health and whether the association differs by gender among Korean Chinese waged workers in South Korea. METHODS: We conducted a pooled cross-sectional analysis using data of 13,443 Korean Chinese waged workers from the Survey on Immigrants' Living Conditions and Labor Force conducted in 2018, 2020, and 2022. Based on perceived ethnic discrimination, asking for fair treatment, and subsequent situational improvement, respondents were classified into the following four groups: "Not experienced," "Experienced, not asked for fair treatment," "Experienced, asked for fair treatment, not improved," and "Experienced, asked for fair treatment, improved." Poor self-rated health was assessed using a single question "How is your current overall health?" We applied logistic regression to examine the association between perceived ethnic discrimination and poor self-rated health, with gender-stratified analyses. RESULTS: We found an association between ethnic discrimination and poor self-rated health among Korean Chinese waged workers. In the gender-stratified analysis, the "Experienced, not asked for fair treatment" group was more likely to report poor self-rated health compared to the "Not experienced" group, regardless of gender. However, gender differences were observed in the group stratified by situational improvements. For male workers, no statistically significant association was found in the "Experienced, asked for fair treatment, improved" group with poor self-rated health (odd ratios: 0.87, 95% confidence intervals: 0.30-2.53). Conversely, among female workers, a statistically significant association was observed (odd ratios: 2.63, 95% confidence intervals: 1.29-5.38). CONCLUSIONS: This study is the first to find an association between perceived ethnic discrimination and poor self-rated health, along with gender differences in the association between situational improvements after asking for fair treatment and poor self-rated health among Korean Chinese waged workers in South Korea.

Evaluation of preoperative oral carbohydrate administration on insulin resistance in off-pump coronary artery bypass patients: A randomised trial.

BACKGROUND: In fasting cardiac surgery patients, preoperative carbohydrate (CHO) drink intake attenuated insulin resistance and improved cardiac metabolism, although its beneficial effects were not evident after cardiac surgery possibly due to cardiopulmonary bypass-related extreme systemic inflammation. OBJECTIVE: We aimed to evaluate whether preoperative CHO intake affected insulin resistance and free-fatty acid (FFA) concentrations in off-pump coronary revascularisation. DESIGN: A randomised controlled trial. SETTING: Primary care in a university hospital in Korea from January 2015 to July 2016. PATIENTS: Sixty patients who underwent elective multi-vessel off-pump coronary revascularisation were randomised into two groups. Three patients were excluded from analysis and 57 patients completed study. INTERVENTION: The CHO group received oral CHO (400 ml) the prior evening and 2 to 3 h before surgery, and the control group was fasted from food and water according to standard protocol. MAIN OUTCOME MEASURES: Insulin resistance was assessed twice, after anaesthetic induction and after surgery via short insulin tolerance test. FFA, C-reactive protein and creatine kinase-myocardial band concentrations were determined serially for 48 h after surgery. RESULTS: Insulin sensitivity was greater (P = 0.002) and plasma FFA concentrations were lower (P = 0.001) after anaesthetic induction in the CHO group compared with the Control group, although there were no intergroup differences after surgery. The postoperative peak creatine kinase-myocardial band concentration was significantly lower in the CHO group compared with the Control group [8.8 (5.4 to 18.2) vs. 6.4 (3.5 to 9.7) ng ml, P = 0.031]. CONCLUSION: A preoperative CHO supplement significantly reduced insulin resistance and FFA concentrations compared with fasting at the beginning of the surgery, but these benefits were lost after off-pump coronary revascularisation. Despite their transient nature, these beneficial effects resulted in less myocardial injury, mandating further studies focused on the impact of preoperative CHO on myocardial ischaemia and cardiac function after coronary revascularisation. TRIAL REGISTRATION: Clinicaltrials.gov identifier: NCT 02330263.

The role of supervisor support in the association between night work and depressive symptoms: a gender-stratified analysis of 22,422 full-time wage workers in South Korea.

Objectives: This study investigated the relationship between night work, supervisor support, and depressive symptoms among full-time wage workers, with a focus on gender differences. Methods: A nationwide sample of 22,422 full-time wage workers from the Sixth Korean Working Conditions Survey (2020-2021) was analyzed. Experiences of night work were categorized into 5 groups based on the number of night work days per month: 0, 1-5, 6-10, 11-15, and 16-31. Depressive symptoms were evaluated using the 5-item World Health Organization Well-Being Index. Supervisor support was assessed with 5 items. Results: Workers who engaged in 1-5 days (prevalence ratio [PR], 1.23; 95% CI, 1.12-1.36) and 6-10 days (PR, 1.17; 95% CI, 1.06-1.30) of night work per month exhibited a higher prevalence of depressive symptoms than those without night work. After stratifying by supervisor support levels, workers with 1-5, 6-10 and 11-15 days of night work per month were more likely to experience depressive symptoms compared to those without night work in the low supervisor support group. In contrast, no association was found between night work (≥ 6 days) and depressive symptoms in the high supervisor support group. Furthermore, gender differences were notable: female workers with 6-10 days (PR, 1.45; 95% CI, 1.23-1.70), and 11-15 days (PR, 1.43; 95% CI, 1.08-1.90) of night work per month exhibited a higher prevalence of depressive symptoms, whereas their male counterparts did not. This pattern of gender difference was also found among those with low supervisor support. Conclusion: Supervisor support may mitigate the adverse effects of night work on depressive symptoms among full-time wage workers, with differences manifested across genders.

Disparities in Workplace Hazards and Organizational Protection Resources by Enterprise Size: A National Representative Study of South Korean Manufacturing Workers.

Background: This study aimed to identify the prevalence of workplace hazards and organizational protection resources according to the size of the enterprise in the manufacturing industry of the Republic of Korea. Methods: We analyzed data of waged workers (weighted N = 5,879) from the Fifth Korean Working Conditions Survey (2017). Enterprise sizes were categorized as "micro enterprises" (less than five employees), "small enterprises" (5-49 employees) and "medium-large enterprises" (50 or more employees). Self-reported exposure to 18 physical, chemical, ergonomic, and psychological hazards were measured. The presence of organizational protection resources such as a labor union, a safety delegate working at the company, designated spaces to deal with safety, and the provision of health and safety information was evaluated. Results: Compared to workers in medium-large enterprises, those in micro enterprises showed a higher proportion of exposure to most of physical, chemical, ergonomic, and psychological hazards, except for exposure to solvents, prolonged sitting, and experiencing a state of emotional unrest. On the other hand, workers in micro enterprises had the lowest proportion of access to organizational protection resources. Conclusion: Our study demonstrates that manufacturing workers at the micro enterprise in the Republic of Korea are exposed to the most hazardous work environment and yet have access to the fewest organizational protection resources.

Ventilation With High or Low Tidal Volume With PEEP Does Not Influence Lung Function After Spinal Surgery in Prone Position: A Randomized Controlled Trial.

BACKGROUND: Spinal surgery in the prone position is accompanied by increased intrathoracic pressure and decreased respiratory compliance. This study investigated whether intraoperative lung protective mechanical ventilation improved lung function evaluated with pulmonary function tests in patients at risk of postoperative pulmonary complications (PPCs) after major spinal surgery in the prone position. METHODS: Seventy-eight patients at potential risk of PPCs were randomly assigned to the protective group (tidal volume; 6 mL/kg predicted body weight, 6 cm H2O positive end-expiratory pressure with recruitment maneuvers) or the conventional group (10 mL/kg predicted body weight, no positive end-expiratory pressure). The primary efficacy variables were assessed by pulmonary function tests, performed before surgery, and 3 and 5 days afterward. RESULTS: Postoperative forced vital capacity (2.17±0.1 L vs. 1.91±0.1 L, P=0.213) and forced expiratory volume in 1 second (1.73±0.08 L vs. 1.59±0.08 L, P=0.603) at postoperative day (POD) 3 in the protective and conventional groups, respectively, were similar. Trends of a postoperative decrease in forced vital capacity (P=0.586) and forced expiratory volume in 1 second (P=0.855) were similar between the groups. Perioperative blood-gas analysis variables were comparable between the groups. Patients in the protective and conventional groups showed similar rates of clinically significant PPCs (8% vs. 10%, P>0.999). CONCLUSIONS: In patients at potential risk of developing PPCs undergoing major spinal surgery, we did not find evidence indicating any difference between the lung protective and conventional ventilation in postoperative pulmonary function and oxygenation.

Protective Effect of Peroxisome Proliferator-Activated Receptor α Activation against Cardiac Ischemia-Reperfusion Injury Is Related to Upregulation of Uncoupling Protein-3.

Activation of peroxisome proliferator-activated receptor α (PPARα) confers cardioprotection, while its mechanism remains elusive. We investigated the protective effect of PPARα activation against cardiac ischemia-reperfusion injury in terms of the expression of uncoupling protein (UCP). Myocardial infarct size and UCP expression were measured in rats treated with WY-14643 20 mg/kg, a PPARα ligand, or vehicle. WY-14643 increased UCP3 expression in vivo. Myocardial infarct size was decreased in the WY-14643 group (76 ± 8% versus 42 ± 12%, P<0.05). During reperfusion, the incidence of arrhythmia was higher in the control group compared with the WY-14643 group (9/10 versus 3/10, P<0.05). H9c2 cells were incubated for 24 h with WY-14643 or vehicle. WY-14643 increased UCP3 expression in H9c2 cells. WY-14643 decreased hypoxia-stimulated ROS production. Cells treated with WY-14643 were more resistant to hypoxia-reoxygenation than the untreated cells. Knocking-down UCP3 by siRNA prevented WY-14643 from attenuating the production of ROS. UCP3 siRNA abolished the effect of WY-14643 on cell viability against hypoxia-reoxygenation. In summary, administration of PPARα agonist WY-14643 mitigated the extent of myocardial infarction and incidence of reperfusion-induced arrhythmia. PPARα activation conferred cytoprotective effect against hypoxia-reoxygenation. Associated mechanisms involved increased UCP3 expression and resultant attenuation of ROS production.