Impact of Wildfire Smoke Exposure on Health in Korea

Purpose@#The characteristic topography and climate often affect the occurrence of large-scale wildfires in the Eastern Gangwon-do region of Korea. However, there are no studies on the health effects of these wildfires in Korea. This study aimed to analyze the differences in medical use between a wildfire-affected area and an adjacent non-affected area before and after a wildfire in 2019 in Gangwon-do, Korea. @*Materials and Methods@#We used medical usage data from the Korean National Health Insurance Corporation. Rates of medical use were determined for citizens of a wildfire-affected area in the Eastern Yeongdong region and a non-affected area in the Western Yeongseo region. Logistic regression analysis was performed considering an increase in medical use per individual as a dependent variable; age, sex, income, smoking, drinking, and exercise were included as confounding variables. @*Results@#The odds ratio for medical use in Yeongdong region increased significantly after 3 days, 3 months, and 1 year after a fire occurred, compared with Yeongseo region. @*Conclusion@#The results of this study confirmed that the use of medical care increased for residents of a wildfire-affected area, compared with those of an adjacent non-affected area. This is the first study on the relationship between wildfires and inpatient medical use in Korea.

Association Between Insomnia and Constipation: A Multicenter Three-year Cross-sectional Study Using Shift Workers' Health Check-up Data

Background@#Although insomnia and constipation are highly prevalent worldwide, studies examining a possible association between them are lacking. We examined the relationship between insomnia and constipation in shift workers who have a high prevalence of insomnia and other diseases. @*Methods@#This study had a multicenter cross-sectional design and conducted using health examination data including self-reported questionnaires. In total, 12,879 and 4,650 shift workers were enrolled in Severance Hospital and Wonju Severance Hospital, respectively, during 2015-2017. Multivariate logistic regression models and subgroup analysis were performed in each center with the same protocol, using a common data model. @*Results@#The mean age of the total population was 44.35 (standard deviation = 8.75); the proportion of males was 56.9%. Female sex, being underweight and non-smoker were strongly associated with an increased risk of constipation symptom (p < 0.001). Pooled odds ratios (ORs) were calculated using ORs of both centers with weights; there was a significant dose–response relationship (sub-threshold 1.76 [95% confidence interval [CI] 1.62–1.91]; moderate 2.28 [95% CI 2.01–2.60]; severe 4.15 [95% CI 3.18–5.41] in the final model, p for trend < 0.001). Subgroup analysis performed by stratifying sex and pooled ORs showed a similar trend to that of the entire group. @*Conclusion@#We observed a strong correlation between insomnia and constipation in this population. Our findings may help in formulating guidelines and policies to improve quality of life in shift workers through the management of sleep quality and proper bowel function. This study is the first to report this relationship among people working in shifts.

Clinical Characteristics of Chronic Cough in Korea / 결핵

Clinical Characteristics of Chronic Cough in Korea / 결핵및호흡기질환

BACKGROUND@#Chronic cough is defined as a cough lasting more than 8 weeks and socio-economic burden of chronic cough is enormous. The characteristics of chronic cough in Korea are not well understood. The Korean Academy of Tuberculosis and Respiratory Diseases (KATRD) published guidelines on cough management in 2014. The current study evaluated the clinical characteristics of chronic cough in Korea and the efficacy of the KATRD guidelines.@*METHODS@#This was a multi-center, retrospective observational study conducted in Korea. The participants were over 18 years of age. They had coughs lasting more than 8 weeks. Subjects with current pulmonary diseases, smokers, ex-smokers with more than 10 pack-years or who quit within the past 1 year, pregnant women, and users of cough-inducing medications were excluded. Evaluation and management of cough followed the KATRD cough-management guidelines.@*RESULTS@#Participants with chronic cough in Korea showed age in the late forties and cough duration of more than 1 year. Upper airway cough syndrome was the most common cause of cough, followed by cough-variant asthma (CVA). Gastro-esophageal reflux diseases and eosinophilic bronchitis were less frequently observed. Following the KATRD cough-management guidelines, 91.2% of the subjects improved after 4 weeks of treatment. Responders were younger, had a longer duration of cough, and an initial impression of CVA. In univariate and multivariate analyses, an initial impression of CVA was the only factor related to better treatment response.@*CONCLUSION@#The causes of chronic cough in Korea differed from those reported in other countries. The current Korean guidelines proved efficient for treating Korean patients with chronic cough.

Development and Validation of a Education Nurse Specialist-Led Education Satisfaction Scale for Nurses Working at Comprehensive Nursing Care Service Wards / 임상간호연구

Purpose@#The purpose of this study was to develop and validate a education nurse specialist-led educational satisfaction scale for nurses working at comprehensive nursing care service wards. @*Methods@#A methodological study was conducted. A total of 237 nurses working at comprehensive nursing care service wards in a general hospital participated in this study. The scale was developed through literature reviews, in-depth interview, development of preliminary items, verification of content validity, development of secondary items, evaluation of construct validity, and extraction of final items. Analysis included exploratory factor analysis, pearson's analysis, and reliability analysis using cronbach's ⍺. @*Results@#The education nurse specialist-led educational satisfaction scale for nurses working at comprehensive nursing care service ward consisted of 21 items. Two factors (critical thinking disposition and clinical competency) were identified which explained 63.5% of the total variance.Cronbach's ⍺ of each factors were >.95. @*Conclusion@#The results suggested that the education nurse specialist-led educational satisfaction scale for nurses working at comprehensive nursing care service wards demonstrated acceptable validity and reliability. Items of the instrument can assess the level of satisfaction with regards to education led by education nurse specialist among nurses working at comprehensive nursing care service wards.

Psychosocial factors affecting sleep quality of pre-employed firefighters:a cross-sectional study

Background@#There have been no health-related studies of pre-employed firefighters without firefighter-specific job-related factors (FSJRF). This study aimed to evaluate the sleep quality of pre-employed firefighters and to examine the relationship between sleep quality and psychosocial factors. @*Methods@#We conducted a self-report questionnaire survey for 602 pre-employed firefighters at 3 Fire Service Academies after brief lecture about sleep. Sleep quality and psychosocial variables such as depression, anxiety, stress and social support were evaluated. The independent 2 sample t-test, χ2 test and multiple logistic regression analysis were used to evaluate the effect of the variables on the sleep quality of pre-employed firefighters. @*Results@#Among a total of 602 people, 347 (57.6%) had good sleep quality and 255 (42.4%) had poor sleep quality. Pittsburgh Sleep Quality Index score of them was 3.29 ± 1.41) and 7.87 ± 2.20), respectively. 24 (4.0%) were evaluated to have insomnia by Insomnia Severity Index.Logistic regression analyses showed that the depression (adjusted odds ratio [aOR]: 5.940, 95% confidence interval [CI]: 3.124–11.292), anxiety (aOR: 4.233, 95% CI: 2.138–8.381), stress (aOR: 2.880, 95% CI: 1.915–4.330) and social support (aOR: 0.959, 95% CI: 0.939–0.980) have a significant effect on sleep quality after adjusted by sex, age, smoking status, drinking status, caffeine intake, past shift working and circadian rhythm type. @*Conclusions@#Depression, anxiety, stress and social support were associated with sleep quality among pre-employed firefighters. Repeated follow-up studies of pre-employed firefighters are needed to further assess their change of sleep quality and identify the FSJRF that may affect the sleep quality of firefighters.

Clinical Characteristics of Chronic Cough in Korea / 결핵및호흡기질환

BACKGROUND@#Chronic cough is defined as a cough lasting more than 8 weeks and socio-economic burden of chronic cough is enormous. The characteristics of chronic cough in Korea are not well understood. The Korean Academy of Tuberculosis and Respiratory Diseases (KATRD) published guidelines on cough management in 2014. The current study evaluated the clinical characteristics of chronic cough in Korea and the efficacy of the KATRD guidelines.@*METHODS@#This was a multi-center, retrospective observational study conducted in Korea. The participants were over 18 years of age. They had coughs lasting more than 8 weeks. Subjects with current pulmonary diseases, smokers, ex-smokers with more than 10 pack-years or who quit within the past 1 year, pregnant women, and users of cough-inducing medications were excluded. Evaluation and management of cough followed the KATRD cough-management guidelines.@*RESULTS@#Participants with chronic cough in Korea showed age in the late forties and cough duration of more than 1 year. Upper airway cough syndrome was the most common cause of cough, followed by cough-variant asthma (CVA). Gastro-esophageal reflux diseases and eosinophilic bronchitis were less frequently observed. Following the KATRD cough-management guidelines, 91.2% of the subjects improved after 4 weeks of treatment. Responders were younger, had a longer duration of cough, and an initial impression of CVA. In univariate and multivariate analyses, an initial impression of CVA was the only factor related to better treatment response.@*CONCLUSION@#The causes of chronic cough in Korea differed from those reported in other countries. The current Korean guidelines proved efficient for treating Korean patients with chronic cough.

Development and Validation of a Education Nurse Specialist-Led Education Satisfaction Scale for Nurses Working at Comprehensive Nursing Care Service Wards / 임상간호연구

Purpose@#The purpose of this study was to develop and validate a education nurse specialist-led educational satisfaction scale for nurses working at comprehensive nursing care service wards. @*Methods@#A methodological study was conducted. A total of 237 nurses working at comprehensive nursing care service wards in a general hospital participated in this study. The scale was developed through literature reviews, in-depth interview, development of preliminary items, verification of content validity, development of secondary items, evaluation of construct validity, and extraction of final items. Analysis included exploratory factor analysis, pearson's analysis, and reliability analysis using cronbach's ⍺. @*Results@#The education nurse specialist-led educational satisfaction scale for nurses working at comprehensive nursing care service ward consisted of 21 items. Two factors (critical thinking disposition and clinical competency) were identified which explained 63.5% of the total variance.Cronbach's ⍺ of each factors were >.95. @*Conclusion@#The results suggested that the education nurse specialist-led educational satisfaction scale for nurses working at comprehensive nursing care service wards demonstrated acceptable validity and reliability. Items of the instrument can assess the level of satisfaction with regards to education led by education nurse specialist among nurses working at comprehensive nursing care service wards.

Psychosocial factors affecting sleep quality of pre-employed firefighters:a cross-sectional study

Background@#There have been no health-related studies of pre-employed firefighters without firefighter-specific job-related factors (FSJRF). This study aimed to evaluate the sleep quality of pre-employed firefighters and to examine the relationship between sleep quality and psychosocial factors. @*Methods@#We conducted a self-report questionnaire survey for 602 pre-employed firefighters at 3 Fire Service Academies after brief lecture about sleep. Sleep quality and psychosocial variables such as depression, anxiety, stress and social support were evaluated. The independent 2 sample t-test, χ2 test and multiple logistic regression analysis were used to evaluate the effect of the variables on the sleep quality of pre-employed firefighters. @*Results@#Among a total of 602 people, 347 (57.6%) had good sleep quality and 255 (42.4%) had poor sleep quality. Pittsburgh Sleep Quality Index score of them was 3.29 ± 1.41) and 7.87 ± 2.20), respectively. 24 (4.0%) were evaluated to have insomnia by Insomnia Severity Index.Logistic regression analyses showed that the depression (adjusted odds ratio [aOR]: 5.940, 95% confidence interval [CI]: 3.124–11.292), anxiety (aOR: 4.233, 95% CI: 2.138–8.381), stress (aOR: 2.880, 95% CI: 1.915–4.330) and social support (aOR: 0.959, 95% CI: 0.939–0.980) have a significant effect on sleep quality after adjusted by sex, age, smoking status, drinking status, caffeine intake, past shift working and circadian rhythm type. @*Conclusions@#Depression, anxiety, stress and social support were associated with sleep quality among pre-employed firefighters. Repeated follow-up studies of pre-employed firefighters are needed to further assess their change of sleep quality and identify the FSJRF that may affect the sleep quality of firefighters.

Relationship between shift work and liver enzymes: a cross-sectional study based on the Korea National Health and Examination Survey (2007–2015)

BACKGROUND: Shift work has well-known adverse effects on health. However, few studies have investigated the relationship between shift work and hepatic disorders. This study aimed to evaluate the association between shift work and abnormal level of liver enzymes. METHODS: The aggregated data from the 2007–2009, 2010–2012, and 2013–2015 cycles of the Korea National Health and Nutrition Examination Survey was used for this study. The χ2 test and multiple logistic regression analysis were used to assess relationship between shift work and abnormal level of liver enzymes stratified by gender. RESULTS: The odds ratio (OR) of abnormal serum level of alanine aminotransferase (abnormal ALT) in female shift workers was higher with 1.31 (95% confidence interval: 1.00–1.71) compared with day workers after adjusting for covariates. After dividing into subgroups of the shift work pattern, the ORs of abnormal liver enzymes for each pattern compared with day work were not significantly higher. CONCLUSIONS: This study provides limited support for the hypothesis that shift work is related to liver enzyme abnormalities, but offers some evidence in favor of the idea that shift work affects female workers more than males on abnormal ALT. Further studies are needed to define the relationship between shift work and abnormal liver enzymes to be carried out as well as the gender difference in the association.

The Relationship between Injury and Socioeconomic Status in Reference to the Fourth Korean National Health and Nutrition Examination Survey

OBJECTIVES: This study aims to investigate the relationship between the total injury experience rate and socioeconomic status based on the fourth Korea National Health and Nutrition Examination Survey (KNHANES). METHODS: By analyzing data from the fourth KNHANES conducted from 2007 to 2009, we estimated the injury experience rate according to socioeconomic status, including the occupational characteristics of 11,837 subjects. Setting the injury experience rate as a dependent variable and socioeconomic status as an independent variable, we performed logistic regression to calculate odds ratios reflecting the likelihood of injury according to socioeconomic status while controlling for relevant covariates. RESULTS: In 797 subjects who had injury experience over the past 1 year, 290 persons (36.4%) had a work-related injury. As their income, home value, and educational status increased, their injury experiences decreased. Among occupational groups, the craft, equipment, machine operating, and assembling workers showed the highest rate (10.6%) of injury experience, and the lowest rate (5.7%) was found in the unemployed group. After adjusting for the confounding variables, the experience of injury was significantly related to several socioeconomic factors: high income (OR = 0.54; 95% CI: 0.34-0.86), high home value (OR = 0.65; 95% CI: 0.43-0.96), low education status (OR = 1.28; 95% CI: 1.07-1.52), and specific occupations such as craft, equipment, machine operating, and assembling work (OR = 1.99; 95% CI: 1.60-2.47), skilled agriculture, forestry and fishery work (OR = 1.43; 95% CI: 1.02-2.01), and simple labor (OR = 1.38; 95% CI: 1.04-1.82). CONCLUSIONS: The injury experience rate differed depending on the socioeconomic status. A negative correlation was found between the injury experience rate and income, low home value, and education level. Moreover, a higher rate of injury experience was found in occupation groups and physical worker groups in comparison to the unemployed group and white-collar worker groups. This study would be useful in selecting appropriate priorities for injury management in Korea.

The Relationship between Waist Circumference and Work-related Injury in Reference to the Fourth Korea National Health and Nutrition Examination Survey

OBJECTIVE: This study aims to investigate the relationship between waist circumference and work-related injury in reference to the fourth Korea National Health and Nutrition Examination Survey. METHODS: By analyzing data from the fourth Korea National Health and Nutrition Examination Survey conducted from 2007 to 2009, we estimated the rate of injury experience according to socioeconomic status, including occupational property, of 8,261 subjects. We performed logistic regression analysis with work-related injury experience rate as dependent variable and waist circumference as an independent variable, Odds ratios (OR) were calculated, which reflect the likelihood of work-related injury experience rate, and 95% confidence interval (95% CI) while controlling for relevant covariates with stratifying by sex, age, nature of injury, site of injury and occupational group. RESULTS: Among 797 persons who had injury experience over the past 1 year, 293 persons (36.8%) had work-related injury experience. After adjusting the confounding variables, the work-related injury was related to abnormal waist circumference (OR = 1.35; 95% CI: 1.02 ~ 1.78). In subgroups, ORs were higher in men (OR = 1.42; 95% CI: 1.02 ~ 1.98), professional, manager, and administrator (OR = 2.41; 95% CI: 1.10 ~ 5.28). Higher rate of injuries were noted in back and waist (OR = 2.92; 95% CI: 1.49 ~ 5.73), and transport accident had increased risk (OR = 1.60; 95% CI: 1.13 ~ 2.28). CONCLUSIONS: Work-related injury rate differed depending on the waist circumference. The abdominal obesity was associated with higher risk of work-related injury. This study would be useful in selecting appropriate priorities for work-related injury management in Korea.

The Relationship of Physical and Psychosocial Risk Factors to Work-related Musculoskeletal Upper Extremity Symptoms amongst Male Automobile Manufacturing Workers / 대한산업의학회지

OBJECTIVES: The objective of this study was to determine the relationship of physical and psychosocial risk factors to work-related musculoskeletal upper extremity symptoms amongst automobile manufacturing workers. METHODS: The cross-sectional study was conducted using male automobile manufacturing workers in order to examine the relationship of physical and psychosocial risk factors to work-related musculoskeletal upper extremity symptoms. A total of 1,793 male workers were asked to complete a self-administered questionnaire. The questionnaire consisted of questions regarding general characteristics, health related behaviors, work-related characteristics, job stress, ergonomic risk factors, and the presence of musculoskeletal symptoms (neck, shoulder, arm, and hand). Work-related musculoskeletal symptoms were evaluated using the National Institute of Occupational Safety and Health (NIOSH) surveillance criteria. In order to measure the physical risk factors, the American National Standard Institute (ANSI) Z-365 Quick checklist was incorporated into the questionnaire. Job stressors were measured using the Korean Occupational Stress Scale (KOSS). A binary logistic regression analysis was performed that examined the relationship of physical and psychosocial risk factors to musculoskeletal symptoms. RESULTS: The result showed that the physical and psychosocial risk factors were associated with musculoskeletal upper extremity symptoms. The workers with high physical risk factors reported more musculoskeletal symptoms than those having low physical risk factors (OR: 2.37, 95% CI: 1.56~3.62). The workers with high job stress were more likely to have an increased risk of musculoskeletal upper extremity symptom compared to those with normal job stress (OR: 2.65, 95% CI: 2.03~3.47). A significant relationship between the combined effects of physical and psychosocial risk factors on musculoskeletal upper extremity symptoms was also found. The workers exposed to high physical risk factors, high job stress, and long working hours were more likely to report musculoskeletal symptoms than those having low physical risk factors, normal job stress and moderate working hours(OR: 2.37, 95% CI: 1.56~3.62). CONCLUSIONS: The results suggest that some physical and psychosocial risk factors increase the risk of work-related musculoskeletal upper extremity symptoms amongst automobile manufacturing workers. In order to prevent or reduce musculoskeletal disorders amongst automobile manufacturing workers, it is strongly recommended to manage the physical psychosocial risks occurring in the workplace.

Job Stress and Self-perceived Fatigue in Korean Farmers / 대한산업의학회지

OBJECTIVES: A growing body of research has documented that job stress has a pivotal role in developing adverse health outcomes. However, little is known about the relationship between farmers' job stress and health outcomes. This study was undertaken to identify the relationship between job stress and self-perceived fatigue in Korean farmers. METHODS: A total of 526 Korean farmers were asked to participate in this study. A self-administered questionnaire was used to assess the participants' general characteristics, job stress and self-perceived fatigue. Job stress was measured using a forty-eight item Farm Stressor Inventory (FSI), and the self-perceived fatigue was estimated by Multidimensional Fatigue Scale (MFS). Binary logistic regression analysis was conducted to examine the relationship between job stress and self-perceived fatigue. RESULTS: The result showed that job stress was associated with self-perceived fatigue. For the farmers with high job stress, the risk of self-perceived fatigue was more likely to increase compared to those with low job stress. For males, labor intensity (OR, 3.88; 95% CI, 1.91~7.89), job environment (OR, 2.45; 95% CI, 1.22~4.93), social support (OR, 2.10; 95% CI, 1.07~4.13), social isolation (OR, 2.45; 95% CI, 1.15~5.60), financial problems (OR, 3.25; 95% CI, 1.53~6.91), uncertainty (OR, 2.48; 95% CI, 1.30~4.75) and health problems (OR, 5.77; 95% CI, 2.46~13.53) were associated with self-perceived fatigue. For females, job environment (OR, 2.23; 95% CI, 1.22~4.08), social isolation (OR, 2.08; 95% CI, 1.05-4.15), physical environment & weather condition (OR, 2.61; 95% CI, 1.33~5.12), financial problems (OR, 2.87; 95% CI, 1.55~5.32), uncertainty (OR, 3.65; 95% CI, 1.95~6.83) and health problems (OR, 3.38; 95% CI, 1.57~7.27) were associated with self-perceived fatigue. CONCLUSIONS: This result suggests that farmers' job stress plays a role in the development of fatigue, and job stressors related to fatigue are slightly different according to gender.

The Relationship between Hospital Departments and Risk of Developing Tuberculosis among Nurses Working at a University Hospitalin Korea: Retrospective Cohort Study / 대한산업의학회지

OBJECTIVES: To investigate the occurring characteristics of pulmonary tuberculosis (TB) among nurses working at a university hospital in Korea. METHODS: A retrospective cohort study was conducted using medical records from a university hospital. A total of 351 nurses without any pulmonary disease were enrolled during 2000~2007, and were followed up until October 2010. To compare with the incidence of TB between occupational subgroups, workplaces were divided into high and low TB-exposure risk departments. For statistical analysis, the relative risks for TB incidences between departments were estimated using Cox proportional hazards models and mean incidences were estimated with person-time years. RESULTS: Seven cases of TB were observed during 2001 person-years. Five and two cases were observed in the high and low TB-exposure risk departments, respectively. The relative risk of TB infection in the high TB-exposure risk departments were 6.52 (95% CI, 1.26~33.60) compared to that in the low TB-exposure risk department. The mean incidence of TB in the total nurses was 0.350% per person-year. CONCLUSIONS: According to the concept of occupational and environmental medicine, high TB-exposure risk departments were more likely to be at increased risk of tuberculosis.

A Case of Mitochondrial Myopathy Showing Severe Hypoxemia during REM Sleep / 수면정신생리

Mitochondrial myopathy is characterized by variable clinical manifestations from mild limb weakness to fatal respiratory failure and central nervous system sequela. But it is a rare event that sleep disordered breathing become a clue of diagnosis for mitochondrial myopathy. We report a case of a 21 year-old man who was diagnosed as mitochondrial myopathy during the investigation for the possible cause of chronic hypoventilation syndrome. Before being admitted to our hospital, he was suspected as having sleep apnea syndrome in another hospital. We re-evaluated the history, physical examination, laboratoy findings and polysomnography in detail. Severe hypoxemia was noted during REM sleep on nocturnal polysomnography and the diagnosis of mitochondrial myopathy was made by muscle biopsy in rectus abdominis muscle. We treated him with bilevel positive airway pressure therapy during sleep and it could reverse the hypoxemia during REM sleep. He could be discharged with improved condition and is being well with the use of this ventilatory assistance.