Increased risk of gastric cancer in workers with occupational dust exposure

Background/Aims@#Workers who are exposed to dust in the workplace tend to show a higher incidence of gastric cancer. Nevertheless, scientific evidence to support an association between dust exposure and the risk of gastric cancer is inadequate. This study aimed to investigate whether or not occupational dust exposure influences the risk of gastric cancer. @*Methods@#We collected the electronic data from the Pneumoconiosis Health Examination (PHE) program, provided by the Ministry of Employment and Labor and the Korea Workers’ Compensation and Welfare Service from 2002 to 2017. The PHE database was linked to the National Health Insurances databases. The age-standardized incidence ratio (SIR) and 95% confidence intervals (CIs) of the risk of gastric cancers were evaluated in workers with occupational dust exposure, and the results were compared to those in the general population. @*Results@#From 2004 to 2015, 1,543 cases of gastric cancer were observed in the male participants, as compared with 1,174 of expected cases, which yielded an SIR of 1.314 (95% CI, 1.249 to 1.380). Under dust exposure, the risk of gastric cancer was increased 23.9% in the male participants (95% CI, 19.9 to 27.5), and the degree of impairment of lung function was inversely related to the risk of gastric cancer. @*Conclusions@#Workers with occupational dust exposure were at higher risk of developing gastric cancer than the general population. Thus, future efforts for the prevention of gastric cancer are necessary for dust exposed workers.

Trends in Obesity Prevalence by Occupation Based on Korean National Health and Nutrition Examination Survey From 1998 to 2015

Background@#It is well known that the prevalence of obesity in Korea is increasing over time, however it is not known how the trends among occupational groups and sex differ in such increasing trends. This study was designed to provide recent trends of obesity among workers in Korea and to identify whether there were differences among occupational groups. @*Methods@#We used data from the Korean National Health and Nutrition Examination Survey, Phases I to VI (1998–2015), to analyze trends in the prevalence of obesity in adult Korean workers. Obesity was defined as a body mass index of 25 kg/m2 or higher. Occupations were classified into 3 groups: (a) nonmanual workers, (b) service/sales workers, and (c) manual workers. @*Results@#During the period of the Korean National Health and Nutrition Examination Survey Phases I to VI, the prevalence of obesity in male workers increased in all occupations (31.1% to 39.5% in manual workers, 32.3% to 38.2% in service/sales workers, and 25.3% to 39.7% in manual workers). However, female workers did not show any particular tendency toward obesity, except for a significant decrease in the prevalence rate in service/sales workers (30.8% to 23.9%, p for trend = 0.0048). @*Conclusion@#The trends of obesity prevalence by sex and occupation were different. For male manual workers, the prevalence rate increased steadily during the data period, while it decreased steadily in female sales/service workers.

Effects of Particulate Respirator Use on Cardiopulmonary Function in Elderly Women: a Quasi-Experimental Study

BACKGROUND@#Individual particulate respirator use may offer protection against exposure to particulate matter < 2.5 µm in diameter (PM(2.5)). Among elderly Korean women, we explored individual particulate respirator use and cardiopulmonary function.@*METHODS@#Recruited in Seoul, Korea, 21 elderly, non-smoking women wore particulate respirators for six consecutive days (exlcuding time spent eating, sleeping, and bathing). We measured resting blood pressure before, during, and after respirator use and recorded systolic and diastolic blood pressure, mean arterial blood pressure, pulse pressure, and lung function. We also measured 12-hour ambulatory blood pressure at the end of the 6-day long experiment and control periods. Additionally, we examined physiological stress (heart rate variability and urinary 8-hydroxy-2′-deoxyguanosine) while wearing the particulate respirators. Person- and exposure-level covariates were also considered in the model.@*RESULTS@#After the 6-day period of respirator use, resting blood pressure was reduced by 5.3 mmHg for systolic blood pressure (P = 0.013), 2.9 mmHg for mean arterial blood pressure (P = 0.079), and 3.6 mmHg for pulse pressure (P = 0.024). However, particulate respirator use was associated with changes in physiological stress markers. A parasympathetic activity marker (high frequency) significantly decreased by 24.0% (P = 0.029), whereas a sympathetic activity marker (ratio of low-to-high frequency) increased by 50.3% (P = 0.045). An oxidative stress marker, 8-hydroxy-2′-deoxyguanosine, increased by 3.4 ng/mg creatinine (P = 0.021) during the experimental period compared with that during the control period. Lung function indices indicated that wearing particulate respirators was protective; however, statistical significance was not confirmed.@*CONCLUSION@#Individual particulate respirator use may prevent PM(2.5)-induced blood-pressure elevation among elderly Korean women. However, the effects of particulate respirator use, including physiological stress marker elevation, should also be considered.TRIAL REGISTRATION: Clinical Research Information Service Identifier: KCT0003526

Effects of Particulate Respirator Use on Cardiopulmonary Function in Elderly Women: a Quasi-Experimental Study

BACKGROUND: Individual particulate respirator use may offer protection against exposure to particulate matter < 2.5 µm in diameter (PM(2.5)). Among elderly Korean women, we explored individual particulate respirator use and cardiopulmonary function.METHODS: Recruited in Seoul, Korea, 21 elderly, non-smoking women wore particulate respirators for six consecutive days (exlcuding time spent eating, sleeping, and bathing). We measured resting blood pressure before, during, and after respirator use and recorded systolic and diastolic blood pressure, mean arterial blood pressure, pulse pressure, and lung function. We also measured 12-hour ambulatory blood pressure at the end of the 6-day long experiment and control periods. Additionally, we examined physiological stress (heart rate variability and urinary 8-hydroxy-2′-deoxyguanosine) while wearing the particulate respirators. Person- and exposure-level covariates were also considered in the model.RESULTS: After the 6-day period of respirator use, resting blood pressure was reduced by 5.3 mmHg for systolic blood pressure (P = 0.013), 2.9 mmHg for mean arterial blood pressure (P = 0.079), and 3.6 mmHg for pulse pressure (P = 0.024). However, particulate respirator use was associated with changes in physiological stress markers. A parasympathetic activity marker (high frequency) significantly decreased by 24.0% (P = 0.029), whereas a sympathetic activity marker (ratio of low-to-high frequency) increased by 50.3% (P = 0.045). An oxidative stress marker, 8-hydroxy-2′-deoxyguanosine, increased by 3.4 ng/mg creatinine (P = 0.021) during the experimental period compared with that during the control period. Lung function indices indicated that wearing particulate respirators was protective; however, statistical significance was not confirmed.CONCLUSION: Individual particulate respirator use may prevent PM(2.5)-induced blood-pressure elevation among elderly Korean women. However, the effects of particulate respirator use, including physiological stress marker elevation, should also be considered.TRIAL REGISTRATION: Clinical Research Information Service Identifier: KCT0003526

Effects of Particulate Respirator Use on Cardiopulmonary Function in Elderly Women: a Quasi-Experimental Study

BACKGROUND@#Individual particulate respirator use may offer protection against exposure to particulate matter < 2.5 µm in diameter (PM(2.5)). Among elderly Korean women, we explored individual particulate respirator use and cardiopulmonary function.@*METHODS@#Recruited in Seoul, Korea, 21 elderly, non-smoking women wore particulate respirators for six consecutive days (exlcuding time spent eating, sleeping, and bathing). We measured resting blood pressure before, during, and after respirator use and recorded systolic and diastolic blood pressure, mean arterial blood pressure, pulse pressure, and lung function. We also measured 12-hour ambulatory blood pressure at the end of the 6-day long experiment and control periods. Additionally, we examined physiological stress (heart rate variability and urinary 8-hydroxy-2′-deoxyguanosine) while wearing the particulate respirators. Person- and exposure-level covariates were also considered in the model.@*RESULTS@#After the 6-day period of respirator use, resting blood pressure was reduced by 5.3 mmHg for systolic blood pressure (P = 0.013), 2.9 mmHg for mean arterial blood pressure (P = 0.079), and 3.6 mmHg for pulse pressure (P = 0.024). However, particulate respirator use was associated with changes in physiological stress markers. A parasympathetic activity marker (high frequency) significantly decreased by 24.0% (P = 0.029), whereas a sympathetic activity marker (ratio of low-to-high frequency) increased by 50.3% (P = 0.045). An oxidative stress marker, 8-hydroxy-2′-deoxyguanosine, increased by 3.4 ng/mg creatinine (P = 0.021) during the experimental period compared with that during the control period. Lung function indices indicated that wearing particulate respirators was protective; however, statistical significance was not confirmed.@*CONCLUSION@#Individual particulate respirator use may prevent PM(2.5)-induced blood-pressure elevation among elderly Korean women. However, the effects of particulate respirator use, including physiological stress marker elevation, should also be considered.TRIAL REGISTRATION: Clinical Research Information Service Identifier: KCT0003526

Comparison of work environment and occupational injury in direct and indirect employment in Korea and Europe

BACKGROUND: To investigate the risk of injury for indirect employment in Korea, we compared work environment, workplace exposure, and injury risk according to the type of employment contract between Korea and European Union (EU) countries. METHODS: We analyzed data of blue-collar workers from the fourth Korean Working Conditions Survey (2014) and the sixth European Working Conditions Survey (2015) and compared workplace risk factors and preventive factors for occupational injuries. Multiple logistic regression analysis was conducted to identify the relationship between occupational injury and the type of employment contract after adjusting for age and sex. RESULTS: For descriptive characteristics, a relatively older age, lower income, lower proportion of full-time work, greater proportion in small-sized companies, and fewer unionizations were noted in indirect employment in Korea than in direct employment. Workplace exposure was significantly higher in indirect employment in both Korea and Europe. Among safety-related factors, indirect employment in both Korea and Europe lacked the support of company education, coworkers, and supervisors. Indirectly employed blue-collar workers had a significantly higher risk of occupational injury than those directly employed in Korea (odds ratio [OR]: 1.876), whereas there was no significant difference between directly and indirectly employed workers in EU countries (OR: 1.038). CONCLUSIONS: Indirectly employed blue-collar workers have an increased risk of occupational injury in Korea.

Occupational Characteristics of Semiconductor Workers with Cancer and Rare Diseases Registered with a Workers' Compensation Program in Korea

BACKGROUND: The aim of this study was to describe the types of diseases that developed in semiconductor workers who have registered with the Korea Workers' Compensation and Welfare Service (KWCWS) and to identify potential common occupational characteristics by the type of claimed disease. METHODS: A total of 55 semiconductor workers with cancer or rare diseases who claimed to the KWCWS were compared based on their work characteristics and types of claimed diseases. Leukemia, non-Hodgkin lymphoma, and aplastic anemia were grouped into lymphohematopoietic (LHP) disorder. RESULTS: Leukemia (n = 14) and breast cancer (n = 10) were the most common complaints, followed by brain cancer (n = 6), aplastic anemia (n = 6), and non-Hodgkin lymphoma (n = 4). LHP disorders (n = 24) accounted for 43%. Sixty percent (n = 33) of registered workers (n = 55) were found to have been employed before 2000. Seventy-six percent (n = 42) of registered workers and 79% (n = 19) among the registered workers with LHP (n = 24) were found to be diagnosed at a relatively young age, ≤40 years. A total of 18 workers among the registered semiconductor workers were finally determined to deserve compensation for occupational disease by either the KWCWS (n = 10) or the administrative court (n = 8). Eleven fabrication workers who were compensated responded as having handled wafers smaller than eight inches in size. Eight among the 18 workers compensated (44 %) were found to have ever worked at etching operations. CONCLUSION: The distribution of cancer and rare diseases among registered semiconductor workers was closely related to the manufacturing era before 2005, ≤8 inches of wafer size handled, exposure to clean rooms of fabrication and chip assembly operations, and etching operations.

Association Between Occupational Physicochemical Exposures and Headache/Eyestrain Symptoms Among Korean Indoor/Outdoor Construction Workers

BACKGROUND: Headache/eyestrain symptoms are common health problems that people experience in daily life. Various studies have examined risk factors contributing to headache/eyestrains, and physicochemical exposure was found to be a leading risk factor in causing such symptoms. The purpose of this study was to examine the relationship of headache/eyestrain symptoms with physicochemical exposure among Korean construction workers depended on worksite.METHODS: This study used data from the 4th Korean Workers Conditions Survey and selected 1,945 Korean construction workers as participants. Multivariable logistic regression analysis was used to determine the relationship.RESULTS: Exposure to vibrations among all construction workers affected the moderate exposure group [odds ratio (OR) 1.53, 95% confidence interval (CI) 1.01–2.32], the high exposure group (OR 1.77 95%CI 1.17–2.67), and the indoor high exposure group (OR 1.61, 95%CI 1.02-2.55) and among outdoor construction workers, the moderate group (OR 6.61, 95%CI 15.4–28.48) and the high group (OR 6.61, 95%CI 1.56–27.98). When exposed to mist, dust, and fumes, the indoor high exposure group was significantly affected (OR 1.63, 95%CI 1.07–2.47). All construction workers exposed to organic solvents were affected, high exposure group (OR 1.69, 95%CI 1.15–2.49) and indoor high exposure group (OR 1.77, 95%CI 1.08–2.89). The high exposure group in all construction worker (OR 1.70, 95%CI 1.20–2.42) and the indoor high exposure group (OR 1.83, 95%CI 1.17–2.89) also were affected by secondhand smoking exposure.CONCLUSION: Many physicochemical exposure factors affect headache/eyestrain symptoms among construction workers, especially indoor construction workers, suggesting a deficiency in occupational hygiene and health environments at indoor construction worksites.

Presenting Differences in Smoking Rates among Working Groups for Smoking Cessation Policies

No abstract available.

Reference Values for Spirometry Derived Using Lambda, Mu, Sigma (LMS) Method in Korean Adults: in Comparison with Previous References

BACKGROUND: The present study aimed to update the prediction equations for spirometry and their lower limits of normal (LLN) by using the lambda, mu, sigma (LMS) method and to compare the outcomes with the values of previous spirometric reference equations. METHODS: Spirometric data of 10,249 healthy non-smokers (8,776 females) were extracted from the fourth and fifth versions of the Korea National Health and Nutrition Examination Survey (KNHANES IV, 2007–2009; V, 2010–2012). Reference equations were derived using the LMS method which allows modeling skewness (lambda [L]), mean (mu [M]), and coefficient of variation (sigma [S]). The outcome equations were compared with previous reference values. RESULTS: Prediction equations were presented in the following form: predicted value = e {a + b × ln(height) + c × ln(age) + M − spline}. The new predicted values for spirometry and their LLN derived using the LMS method were shown to more accurately reflect transitions in pulmonary function in young adults than previous prediction equations derived using conventional regression analysis in 2013. There were partial discrepancies between the new reference values and the reference values from the Global Lung Function Initiative in 2012. CONCLUSION: The results should be interpreted with caution for young adults and elderly males, particularly in terms of the LLN for forced expiratory volume in one second/forced vital capacity in elderly males. Serial spirometry follow-up, together with correlations with other clinical findings, should be emphasized in evaluating the pulmonary function of individuals. Future studies are needed to improve the accuracy of reference data and to develop continuous reference values for spirometry across all ages.

Impacts of Return-to-Work Type and Period on Job Retention in Workers with Occupational Injuries and Diseases

BACKGROUND: Despite the necessity of job retention in achieving return-to-work (RTW) goals, many workers leave their jobs after returning to work. The objective of this study was to examine the impacts of RTW type and period on job retention in Korean workers with occupational injuries and diseases. METHODS: Data were derived from the Panel Study of Worker's Compensation Insurance, including data from 2,000 systemically sampled workers who had finished recuperation in 2012; three waves of survey data were included in the analyses. Workers who returned to work (n = 1,610) were included in the analysis of the relationship between RTW type and job retention, and 664 workers who returned to their original workplaces were included in the analysis of the relationship between RTW period and job retention. The participants completed a questionnaire, and administrative data were provided by workers' compensation insurance. RESULTS: A Cox proportional-hazards regression analysis showed an increased hazard ratio (HR) for non-retention of 2.66 (95% confidence interval, 2.11–3.35) in reemployed workers compared to that in workers returning to their original workplaces. Among workers returning to their original workplaces, HRs for non-retention were increased in workers with a RTW period of 13–24 months (3.03 [1.52–6.04]) and > 24 months (5.33 [2.14–13.25]) compared to workers with a RTW period of ≤ 3 months. CONCLUSION: RTW type and period were significantly related to job retention, suggesting that policies for promoting job retention rate should be implemented.

Silica exposure and work-relatedness evaluation for occupational cancer in Korea

Crystalline silica has been classified as a definite carcinogen (Group 1) causing lung cancer by the International Agency for Research on Cancer (IARC). In Korea, crystalline silica has been the most common causal agent for workers to apply to the Korea Workers' Compensation and Welfare Service (KWCWS). We used KWCWS data to evaluate workers' crystalline silica exposure levels according to their occupations and industries, and reviewed research papers describing the dose-response relationship between cumulative exposure levels and lung cancer incidence. In addition, we reviewed lung cancer cases accepted by the KWCWS, and suggest new criteria for defining occupational cancer caused by crystalline silica in Korea. Rather than confining to miners, we propose recognizing occupational lung cancer whenever workers with pneumoconiosis develop lung cancer, regardless of their industry. Simultaneous exposure and lag time should also be considered in evaluations of work-relatedness.

Overview of occupational cancer in painters in Korea

Comprehensive consideration is necessary for setting guidelines to evaluate evidence of occupational cancer in painters due to work-related exposure to carcinogens in paint (a phenomenon termed herein as “work-relatedness”). The aim of the present research is to perform a comprehensive review and to suggest criteria for the provision of compensation for occupational neoplasm among painters in Korea. In order to perform a comprehensive review, this study assessed and evaluated scientific reports of carcinogenicities from the International Agency for Research on Cancer (IARC) and the Industrial Injuries Advisory Council (IIAC), as well as reviewed the existing literature about occupational exposure among painters in Korea and the epidemiologic investigations of claimed cases of cancer among painters in Korea. The IARC declares that occupational exposures in commercial painting are classified as Group 1 carcinogens for lung cancer and bladder cancer among painters. The epidemiologic studies show consistent causal relationships between occupational exposure in painters and cancers such as lung cancer [meta relative risk: 1.34 (95% confidence intervals (CIs): 1.23-1.41)] and bladder cancer [meta relative risk: 1.24 (95% CIs: 1.16-1.33)]. In reviewing occupational cancer risks for commercial painters, the Industrial Injuries Advisory Council (IIAC) confirms occupational cancer risks for lung and bladder cancer among commercial painters. According to the IIAC, however, the elevated cancer risks reported in existing literature are not doubled in either lung or bladder cancer in commercial painters relative to the risks of these cancers in the general population. Based on our review of existing Korean articles on the topic, painters are exposed to potential carcinogens including polycyclic aromatic hydrocarbons (PAHs), benzene, hexavalent chrome, crystalized silica, asbestos, and other agents, and relative levels are estimated within commercial painting processes. However, the cancer risks of occupational exposure to Group 1 carcinogens for lung and bladder cancer in painters per se are not fully assessed in existing Korean articles. Total work duration, potential carcinogens in paint, mixed exposure to paints across various industries such as construction and shipbuilding, exposure periods, latent periods, and other factors should be considered on an individual basis in investigating the work-relatedness of certain types of cancer in commercial painters.

Effect of teacher's working conditions on voice disorder in Korea: a nationwide survey

BACKGROUND: Korean teacher’s working conditions are deteriorating. There is concern about the deterioration of teachers’ health and voice disorder is one of the most common problems. Teacher’s vocal health is important for them and their students. The aim of the present study was to investigate working conditions that may affect voice disorders. METHODS: In all, 79 primary and secondary schools were randomly selected for a nationwide school system survey (N = 3345). In 64 schools, 1617 (48.3%) teachers participated via a postal self-report questionnaire from June 2016 to August 2016. After applying inclusion and exclusion criteria, data from 1301 teachers’ were used for analysis. Multiple logistic regression was used to investigate the associations between general, work-related factors, and frequent voice disorders (fVDs) to estimate the adjusted odds ratio(aOR). RESULTS: Teachers who reported voice symptoms more than once a week (fVD) made up 11.6%. In a multiple logistic regression, fVD was significantly associated with female, difficulty in applying for sick leave as needed, music teachers (primary school), and less than 6 h of sleep per day (primary school). The aOR for fVD was 2.72 (0.83–8.10) in the longest working hours group (> 52 h/wk) among the primary school teachers, and 1.90 (0.80–4.73) in the longest class hour group (≥ 20 h/wk), 1.52 (0.90–2.62) in homeroom teachers among the secondary school teachers, but not statistically significant. CONCLUSIONS: Korean teachers’ working conditions are associated with fVDs. The school health system must take steps to prevent and treat voice disorders of teachers.

Prediction of Return-to-original-work after an Industrial Accident Using Machine Learning and Comparison of Techniques

BACKGROUND: Many studies have tried to develop predictors for return-to-work (RTW). However, since complex factors have been demonstrated to predict RTW, it is difficult to use them practically. This study investigated whether factors used in previous studies could predict whether an individual had returned to his/her original work by four years after termination of the worker's recovery period. METHODS: An initial logistic regression analysis of 1,567 participants of the fourth Panel Study of Worker's Compensation Insurance yielded odds ratios. The participants were divided into two subsets, a training dataset and a test dataset. Using the training dataset, logistic regression, decision tree, random forest, and support vector machine models were established, and important variables of each model were identified. The predictive abilities of the different models were compared. RESULTS: The analysis showed that only earned income and company-related factors significantly affected return-to-original-work (RTOW). The random forest model showed the best accuracy among the tested machine learning models; however, the difference was not prominent. CONCLUSION: It is possible to predict a worker's probability of RTOW using machine learning techniques with moderate accuracy.

Sleepiness while driving and shiftwork patterns among Korean bus drivers

BACKGROUND: Sleepiness while driving has been regarded as a major cause of death due to traffic accidents. We compared the degree of sleepiness across five different working time periods (first, morning, post-lunch, afternoon, and last) among Korean bus drivers with different shift types (Daily two shift/Alternating day shift). METHOD: We interviewed 332 bus drivers with two shift types (Daily two shift, 128; Alternating day shift, 204). The questionnaire included demographic information (age, alcohol consumption and history of disease), a sleep disorder diagnosed by a doctor, job duration, the number of workdays in the past month, average working hours per workday and week, sleepiness while driving (Karolinska Sleepiness Scale), and sleeping time for both workdays and off-days. We conducted log-binomial regression analyses and produced prevalence ratios (PRs) of severe sleepiness (KSS ≥ 7) while driving with 95% confidence intervals (95% CI) to identify the difference in sleepiness for five working times between both groups. RESULTS: For the first and morning periods, there were no statistically significant differences in the KSS scores between the two groups. However, from lunch to last driving, drivers with Alternating day shift had a much larger proportion of severe sleepiness than those on Daily two shift. Thirteen (10.2%), 2 (1.6%) and 7 (5.5%) Daily two shift workers reported severe sleepiness in the post-lunch, afternoon and last periods. In contrast, 81 (39.7%), 63 (30.9%) and 64 (31.4%) of Alternating day shift drivers experienced severe sleepiness during the post-lunch, afternoon and last driving periods (p < 0.0001). According to the log-binomial regression analyses, Alternating day shift was associated with severe sleepiness from lunch to last driving. After adjusting for job duration, alcohol consumption and sleeping time on workdays, the PRs were 3.97 (95% CI: 2.29–6.90) post-lunch, 18.26 (95% CI: 4.51–73.89) in the afternoon and 5.71 (95% CI: 2.51–12.99) for the last driving period. CONCLUSION: We found that Alternating day shift bus drivers suffered from more sleepiness while driving from lunch to last driving than Daily two shift bus drivers. This difference may be because Alternating day shift drivers had more irregular work schedules and longer working hours per day and week.

Association between shift work and microalbuminuria: data from KNHANES(2012–2014)

BACKGROUND: Shift work disturbs workers' biological clocks and this condition can cause various health problems including cardiovascular disease. The elevated albuminuria level has been significantly associated with the risk of the cardiovascular disease even within a normal reference range. Therefore, this study aimed to investigate the association between shift work and microalbuminuria. METHODS: Workers aged over 20 years from the fifth and sixth Korea National Health and Nutrition Examination Survey(KNHANES 2012–2014; n = 3000) were included in this analysis. The multiple logistic regression analysis was performed to determine the association between shift work and microalbuminuria stratified by gender. RESULTS: The prevalence of microalbuminuria in male subjects was higher among day workers, but the difference was not significant. However, the prevalence of microalbuminuria among females was higher in shift workers with statistical significance. For female, the Odds ratio of microalbuminuria in shift workers was significantly higher with 1.86 (95% CI 1.02–3.39) compared with day workers. After dividing into 5 subgroups of the shift work pattern, the odds ratio of microalbuminuria for fixed night shift was significantly higher at 4.68 (95% CI 1.29–17.00) compared with day workers. CONCLUSIONS: This study showed that shift work was associated with microalbuminuria in female workers. Especially we found out the association between fixed night shift and microalbuminuria in female workers.

Risk factors associated with mortality from pneumonia among patients with pneumoconiosis

BACKGROUND: The aim of this study was to evaluate factors associated with increased risk of mortality from pneumonia among patients with pneumoconiosis. METHODS: Medical records of 103 pneumoconiosis patients hospitalized for pneumonia were investigated. Seven patients who had lung cancer or other malignancy and 13 patients with insufficient medical record were excluded. Two female patients were excluded due to small number to analyze. The subjects were divided into two groups by clinical outcome of pneumonia, the deceased group and the survival group. The two groups were compared in terms of age, smoking history, episode of recent pneumonia, concomitancy of interstitial fibrosis or fungal ball infection, extent of small opacities, grade of large opacities and results of spirometry. Multiple logistic regression was applied to determine the association between these variables and mortality from pneumonia. RESULTS: The deceased group showed more frequent history of recent pneumonia (p = 0.006), higher prevalence of interstitial fibrosis (p = 0.007) and longer hospitalization period (p = 0.044). The proportion of subjects who had decreased FVC, less than 70 % of predicted value, was higher in the deceased group (p < 0.001). In multiple logistic regression, after adjusting age, smoking history, recent pneumonia, fungal ball, large opacity, profusion and FVC (or FEV1) less than 70 % of predicted value, history of recent pneumonia, concomitancy of interstitial fibrosis, type of pneumoconiosis and fungal ball presented statistically significant association with mortality from pneumonia. CONCLUSIONS: The concomitancy of fungal ball or interstitial fibrosis, history of recent pneumonia within last 90 days, type of pneumoconiosis, FVC less than 70 % of predicted value, FEV1 less than 70 % of predicted value presented statistically significant association with mortality from pneumonia. More attention should be given to patients who have such factors when treating pneumonia with pneumoconiosis.

Factors associated with suicide ideation among subway drivers in Korea

BACKGROUND: There were several suicide events of subway drivers in Korea. The aim of this study is to explore work-related factors associated with suicide ideation among subway drivers. METHODS: We analyzed data from 980 male subway drivers. A section of the Korean version of the Composite International Diagnostic Interview (K-CIDI 2.1) was administered by trained interviewers to judge whether a driver has suicide ideation and to diagnose psychiatric disorders. A questionnaire was also administered to collect data on sociodemographic characteristics, work environments, occupational stress, person under train (PUT) experience, and work-related problems. Occupational stress was examined by using the Korean Occupational Stress Scale (KOSS). Logistic regression was applied to evaluate the association between work-related factors and suicide ideation among subway drivers. RESULTS: Regarding work-related problems, conflict with passengers and sudden stops due to the emergency bell were significantly associated with suicide ideation. MDD, PTSD, and panic disorder were strongly associated with suicide ideation. In the analysis of occupational stress, insufficient job control (OR 2.34) and lack of reward (OR 2.52) were associated with suicide ideation even after being adjusted for psychiatric disorders and other work-related factors. CONCLUSIONS: Insufficient job control and lack of reward were associated with suicide ideation among subway drivers. Strategies for drivers to have autonomy while working and to achieve effort-reward balance should be implemented. Furthermore, drivers who have experienced negative work-related problems should be managed appropriately.

Work-related COPD after years of occupational exposure

BACKGROUND: Cigarette smoking is known as the most important risk factor of chronic obstructive pulmonary disease (COPD). However, occupational exposure to other substances can result in COPD. CASE REPORT: A 76-year-old man with occupational exposures to mixtures of silica dust, gas, and fumes for 10 years and with a 25 pack-year smoking history was diagnosed with COPD. His computed tomogram scan revealed some hyperinflation with emphysematous change in both upper lobes. In the pulmonary function tests, his post-bronchodilator forced vital capacity (FVC), forced expiratory volume in one second (FEV1), and FEV1/FVC% were 2.20 L (67% of the predicted value), 1.12 L (52% of the predicted value), and 51%, respectively, indicating moderate COPD. This case of COPD was confirmed as a work-related disease by the Occupational Lung Disease Research Institute in Korea Workers' Compensation & Welfare Service. CONCLUSION: Exposure to various substances such as silica dust, gas, and fumes from furnace and boiler installation was likely the cause of COPD in this patient. Thus, occupational exposure should be considered an important risk factor of COPD.