Chunhui Suh

Effectiveness of a Comprehensive Stress Management Program to Reduce Work-Related Stress in a Medium-Sized Enterprise

ObjectivesTo assess the effectiveness of a comprehensive workplace stress management program consisting of participatory action-oriented training (PAOT) and individual management.MethodsA comprehensive workplace stress management program was conducted in a medium-sized enterprise. The baseline survey was conducted in September 2011, using the Korean Occupational Stress Scale (KOSS) and Worker’s Stress Response Inventory (WSRI). After implementing both organizational and individual level interventions, the follow up evaluation was conducted in November 2011.ResultsMost of the workers participated in the organizational level PAOT and made Team-based improvement plans. Based on the stress survey, 24 workers were interviewed by a researcher. After the organizational and individual level interventions, there was a reduction of several adverse psychosocial factors and stress responses. In the case of blue-collar workers, psychosocial factors such as the physical environment, job demands, organizational system, lack of rewards, and occupational climate were significantly improved; in the case of white-collar workers, the occupational climate was improved.ConclusionsIn light of these results, we concluded that the comprehensive stress management program was effective in reducing work-related stress in a short-term period. A persistent long-term follow up is necessary to determine whether the observed effects are maintained over time. Both team-based improvement activities and individual interviews have to be sustainable and complementary to each other under the long-term plan.

The impact of long working hours on psychosocial stress response among white-collar workers

This study examined the association between long working hours and psychosocial stress responses. In total, 1,122 white-collar workers from a company in Korea completed self-administered questionnaires following a lecture about the study aim, procedures, and confidentiality. Psychosocial stress responses were evaluated using the Psychosocial Well-being Index - Short Form (PWI-SF), and psychosocial working conditions were evaluated with the Korean Occupational Stress Scale - Short Form (KOSS-SF). Multivariate logistic regression analysis was performed after adjusting for demographic variables and psychosocial working conditions to examine associations between long working hours and psychosocial stress responses. In comparison with the reference group, which worked 40–44 hours per week, the crude odds ratio (OR) of the respondents who worked 60 or more hours was 4.56 (95% confidence interval (CI), 2.55–8.15) in terms of psychosocial stress responses. After adjusting for demographic variables, the adjusted OR of those working ≥60 hours was 5.61 (95% CI, 3.01–10.47). After adjusting for both demographic variables and psychosocial working conditions, the adjusted OR of those working ≥60 hours was 3.25 (95% CI, 1.56–6.79). This study found that long working hours are significantly related to psychosocial stress responses among white-collar workers in one Korean company.

Serum concentrations of per- and poly-fluoroalkyl substances and factors associated with exposure in the general adult population in South Korea

Per- and polyfluoroalkyl substances (PFASs) are ubiquitous contaminants found worldwide, including in South Korea. As a result, they are frequently detected in Koreans. However, there is limited representative data and information on potential sources in Korea. Therefore, we measured the serum concentrations of ten PFASs in nationally representative samples of the Korean population (n=1874, 18-69 years) and evaluated the factors associated with their exposure. Serum PFOS, PFDA, PFOA, and PFNA were detected in nearly all participants (83.1-99.9%). However, serum PFPA, PFHxA, and PFHpA were almost undetected (<0.5% of participants). PFOS had the highest population-weighted geometric mean of 10.23ng/mL (95% CI: 9.99-10.47), which was followed by PFOA with 2.85ng/mL (95% CI: 2.73-2.97) and PFDA with 2.17ng/mL (95% CI: 2.12-2.23). PFNA, PFDA, PFHxS, PFOA, and PFOS concentrations were higher in males (p<0.001) and older adults (p<0.001). PFNA was higher in those who used wax, polish, and water-resistant materials (adjusted proportional change=1.14; 95% CI: 1.08-1.22), and those who ate cooked fish (1.16; 95% CI: 1.03-1.31) compared to those who ate nearly no fish. PFDA was higher in those who used herbicides and pesticides (1.05; 95% CI: 1.02-1.09), those who drank beverages in a plastic bag on a daily basis (1.10; 95% CI: 1.03-1.19), and those who ate raw fish (1.15; 95% CI: 1.03-1.29) or cooked fish (1.13; 95% CI: 1.05-1.23) compared to those who ate nearly no fish. PFHxS was higher in those who used traditional Korean health supplement foods (1.08; 95% CI: 1.01-1.15). PFOA was higher in those who used plastic wrap in a microwave daily or weekly (1.08; 95% CI: 1.00-1.16), and those who used disposable paper cups (1.07; 95% CI: 1.01-1.13). PFOS was lower in underweight participants (0.84; 95%CI: 0.75-0.93) compared to those who were obese, and higher in those who exercised regularly (1.08; 95% CI: 1.03-1.14) or irregularly (1.06, 95% CI: 1.01-1.12) compared to those who did not exercise. Subjects who used severely damaged Teflon appliances had lower concentrations of PFOA (0.78, 95% CI: 0.65-0.95), while regular use of Gore-Tex goods was related to higher PFNA (1.15, 95% CI: 1.03-1.28) and PFDA (1.11; 95% CI: 1.02-1.20) levels. These findings suggest that most Koreans are frequently exposed to PFASs, and that serum concentrations of PFASs vary with age, sex, and exposure factors.

Factors associated with total mercury concentrations in maternal blood, cord blood, and breast milk among pregnant women in Busan, Korea

This study investigated the concentration of total mercury (THg) in maternal blood, cord blood, and breast milk, and its association with dietary factors. A total of 127 pregnant women in Busan, Korea were recruited. Maternal blood, cord blood, and breast milk were collected at 36 weeks of gestation, at delivery, and at one week after birth, respectively. Information about dietary habits and other factors were obtained from each subject. The mean THg concentrations in maternal blood, cord blood, and breast milk were 3.12±1.36 μg/L, 5.46±2.41 μg/L, and 0.91±2.08 μg/L, respectively. Positive correlations were found between log-transformed THg concentrations in maternal blood and cord blood (r=0.829, p<0.001), and between maternal blood and breast milk (r=0.296, p=0.001). Multiple linear regression analysis showed that the log-transformed concentration of THg in maternal blood was positively correlated with fish consumption (β=0.345, p<0.0001) and negatively correlated with bean consumption (β=-0.055, p=0.048). Fish consumption (β=0.482, p<0.0001) and maternal age (β=0.025, p=0.033) were positively associated with the concentration of THg in cord blood, while negative correlations were found for bean consumption (β=-0.134, p=0.027) and parity (β=-0.172, p=0.015). Beef consumption (β=0.031, p=0.007) was positively associated with log-transformed THg concentrations in breast milk, while negative correlations were found for bean consumption (β=-0.019, p=0.003) and maternal age (β=-0.083, p=0.004). Our study found that both the dietary and demographic factors differently affected to THg concentrations among samples of maternal blood, cord blood, and breast milk.

Distribution of PFOA and PFOS in maternal blood, cord blood and breast milk in Busan

Objectives: Perfluorooctanoic acid (PFOA) and perfluorooctane sulfonate (PFOS) are man-made, persistent global pollutants widely diffused throughout the environment. They have been even found in the cord blood and breast milk of humans. Furthermore evidence of developmental toxicity in animals exists. To assess the distribution of maternal and fetal exposure to PFOS and PFOA, we analyzed paired maternal blood, cord blood and breast milk samples. Methods: Maternal blood, cord blood and breast milk were collected from 150 volunteers from the general population (aged 20-40, mean ) of the city of Busan in 2009-2010. The samples were extracted using the weak anion exchange and solid-phase extraction methods and quantified by high-performance liquid chromatograph (HPLC, Agilent 1200 Series) coupled with an Triple Quad LC-MS/MS system (Agilent 6410). Results: Median PFOA and PFOS concentrations in maternal blood were 2.18 and 3.32 ng/ml, in cord blood were 0.83 and 0.58 ng/ml, and in breast milk were 0.13 and 0.11 ng/ml, respectively. PFOS and PFOA concentrations were significantly correlated among matrices (Spearsons , p = 0.05 for maternal blood; , p p

Effects of shift work on abdominal obesity among 20–39-year-old female nurses: a 5-year retrospective longitudinal study

BackgroundThis study aimed to investigate the effects of shift work on abdominal obesity among young and middle-aged female nurses during a 5-year retrospective study.MethodsThis retrospective study included female nurses (20–39 years old) who worked at a university hospital in Korea and had available health screening results from 2010–2015. Among 2,611 employees, 934 healthy 20–39-year-old female nurses were identified, and data regarding their demographic information (age and date of employment), waist circumferences (WC), and lifestyle factors (alcohol and exercise) were obtained. Abdominal obesity was defined as a WC of ≥80 cm, based on the World Health Organization’s Asia-West Pacific standard in 2000. The mean WC change from baseline was analyzed using the paired t test, and the association between shift work and abdominal obesity was analyzed using the generalized estimating equation.ResultsCompared to all day workers (both age groups), the 20–29-year-old nurses did not exhibit significant changes in WC at each follow-up. However, among the 30–39-year-old nurses, shift workers exhibited a significant change in WC (vs. baseline) during years 4 and 5, compared to day workers. After adjusting for effective confounders and stratifying the participants according to age, the 20–29-year-old nurses exhibited an odds ratio of 3.21 (95 % confidence interval: 1.29–7.98) for shift work-associated obesity, although the odds ratio for the 30–39-year-old nurses was not statistically significant.ConclusionIn the study population, shift work was associated with a significant change in mean WC among 30–39-year-old nurses, and the shift work-associated risk of abdominal obesity was significant among 20–29-year-old nurses. These results indicate that shift work may influence abdominal obesity differently in 20–29-year-old and 30–39-year-old female nurses.

Concentration of PFOA and PFOS in Whole Blood and Factors Controlling Their Exposure Among Koreans

Department of Occupational and Environmental Medicine & Institute of Environmental and Occupational Medicine, Pusan Paik Hospital, Inje University, Pusan, KoreaABSTRACT Objectives: This study aimed to assess the concentration of perfluorooctanoic acid (PFOA) andperfluorooctanesulfonate (PFOS) in blood and factors controlling their exposure among Koreans. Methods: Study subjects were selected to include 718 members of the general population residing in fivemetropolitan cities and the Gangwon Province area from August 2008 to January 2009. A questionnaire wasadministered to investigate lifestyle, socio-demographic characteristics, and other related factors. Blood sampleswere collected and extracted using solid-phase extraction and anion-exchange methods, and quantified by high-performance liquid chromatograph (HPLC, Agilent 1200 Series) coupled with a Triple Quad LC-MS/MS system(Agilent 6410). Results: Geometric mean concentrations of PFOA and PFOS in the blood were measured as 1.82 and 6.06 ng/ml, respectively. Mean PFOA and PFOS concentrations generally increased with age in both genders. BloodPFOA concentration was significantly different according to such variables as age, family income, residentialdistrict, and province. Blood PFOS concentration was significantly different by such variables as gender, age,lifestyle factors such as regular exercise, alcohol consumption, and smoking status. Also, family income,hazardous facilities, job classification, and province contributed significantly to differences in blood PFOSconcentration levels.Conclusions: Blood PFOA and PFOS concentrations in Koreans were similar with those found in Japan, theUSA, and Germany, but less than those in Australia. PFOA and PFOS exposure seems to be affected by a varietyof factors in Korea. Therefore, investigation is required for each factor to assess the relative contribution ofdifferent variables. Keywords: perfluorooctanoic acid, perfluorooctane sulfonate, blood concentration, exposure control factors

Perception of and attitude toward ethical issues among Korean occupational physicians

BackgroundOccupational physicians (OPs) have complex relationships with employees, employers, and the general public. OPs may have simultaneous obligations towards third parties, which can lead to variable conflicts of interests. Among the various studies of ethical issues related to OPs, few have focused on the Korean OPs. The aim of the present survey was to investigate the ethical contexts, the practical resolutions, and the ethical principles for the Korean OPs.MethodsAn email with a self-administered questionnaire was sent to members of the Korean Society of Occupational and Environmental Medicine, comprising 150 specialists and 130 residents. The questionnaire was also distributed to 52 specialists and 46 residents who attended the annual meeting of the Korean Association of Occupational and Environmental Clinics in October 2015, and to 240 specialists by uploading the questionnaire to the online community ‘oem-doctors’ in February 2016. The responses to each question (perception of general ethical conflicts, recognition of various ethical codes for OPs, core professional values in ethics of occupational medicine, and a mock case study) were compared between specialists and residents by the chi-squared test and Fisher’s exact test.ResultsResponses were received from 80 specialists and 71 residents. Most participants had experienced ethical conflicts at work and felt the need for systematic education and training. OPs suffered the most ethical conflicts in decisions regarding occupational health examination and evaluation for work relatedness. Over 60% of total participants were unaware of the ethical codes of other countries. Participants thought ‘consideration of worker’s health and safety’ (26.0%) and ‘neutrality’ (24.7%) as the prominent ethical values in professionality ofoccupational medicine. In mock cases, participants chose beneficence and justice for fitness for work and confidential information acquired while on duty, and beneficence and respect for autonomy in pre-placement examinations.ConclusionsThis study evaluated the current perception of and attitude toward ethical issues among the Korean OPs. These findings will facilitate the development of a code of ethics and the ethical decision-making program forthe Korean OPs.

0440 A systemic review and meta-analysis of exhaled nitric oxide in chronic obstructive pulmonary disease: relationship to pulmonary function

Objectives Fractional exhaled nitric oxide (FeNO) has been implicated as a pulmonary biomarker in various respiratory disease, including COPD. Measurement of FeNO is a simple, non-invasive tool for assessing airway inflammation. Neverthless, the usefulness of FeNO measurements in COPD patient in clinical practice is unclear. The objective of this review was to evaluate the efficacy of management of COPD based on FeNO in comparison with pulmonary function test. Method Cochrane library (CENTRAL), MEDLINE, EMBASE and reference lists of articles were searched. The last searches were in July 2013. Results of searches were reviewed against predominantly criteria for inclusion. Relevant studies were selected, assessed and data extracted independently by two people. Participant articles with COPD management based on pulmonary function test compared with FeNO measurement were selected. Risk of bias for each study was assessed using the QUADAS(quality assessment of studies of diagnosis accuracy included in systematic reviews) scale. Results Finally, eight studies were included. Of the eight studies, four were a negative and one were positive correlation between FeNO and pulmonary functions. Three studies were not significant correlation. The various results of studies were effected by characteristics of the patients (COPD severity, smoking status, treatment status) and differences in FeNO measurement methods. Conclusions The studies includes in this review highlight the difficulties of correlation between FeNO and pulmonary function. So, the role of add-on monitoring of FeNO to pulmonary function test is less clear because of the absence of conclusive double-blind, randomised, control studies concerning potential clinical benefits in the management of COPD. Further randomised controlled trials are required.

Discordance in Spirometric Interpretations Based on Korean and Non-Korean Reference Equations

ObjectivesKorean regression models for spirometric reference values are different from those of other ethnic groups. The purpose of this study was to evaluate discordance in spirometric interpretations based on using Korean reference equations versus non-Korean reference equations.MethodsSpirometry was performed on 825 Korean male workers from April 2009 to November 2011. The spirometric patterns and disease severity were evaluated using two Korean equations (Chois and Lees) and three equations for Caucasians (NHANES III, Morriss, and Knudsons), and the results of Chois equation were compared with the non-Korean equations. The spirometric patterns were defined as normal, restrictive, and mild and moderate obstructive.ResultsThe mean differences in the FEV1% and FVC% between the two Korean equations were 2.0 ± 1.3% and 3.5 ± 2.2%, respectively. Morriss equation had the greatest difference in the FEV1% from Chois equation: 32.9 ± 8.5%. Knudsons equation had the greatest difference in the FVC% from Chois equation: 10.5 ± 6.5%.ConclusionsThe two Korean equations shared similar characteristics of spirometric interpretation. The spirometric interpretations of Chois equation were significantly different from those of Morriss equation and Knudsons equation.