Relationship between Bone Mineral Density and Moderate to Severe Chronic Kidney Disease among General Population in Korea

Recent studies in Western countries have reported a significant association between glomerular filtration rate (GFR) and bone mineral density (BMD) in the absence of dialysis among the general population. However, there have been few studies regarding renal function and BMD among Korean or Asian subjects with moderate to severe (stage 3 or 4) chronic kidney disease (MS-CKD). The aim of the present study was to investigate the association between MS-CKD and BMD in the general Korean population. BMD, serum creatinine and other measures were obtained from 3,190 subjects (1,428 males and 1,762 females; the fourth Korean National Health and Nutrition Examination Survey). GFR was estimated using the Cockcroft-Gault formula, with adjustment for body surface area. After adjustment for all variables, multiple regression analysis showed that BMD in the femur neck, total femur and lumbar spine were positively associated with eGFR in both males and females. Additional analysis showed that MS-CKD was also significantly associated with osteoporosis in both males and females (odds ratio [OR] 2.20, 95% confidence interval [CI] 1.15-4.20 in males; and OR 1.96, 95% CI 1.33-2.88 in females). Individuals with MS-CKD may be at higher risk of osteoporosis even among Asians.

The Factors Affecting Physical Fitness Level of Female Flight Attendants / 한국직업건강간호학회지

PURPOSE: This study is aimed at obtaining the information on the physical fitness level of female flight attendants at a local airline. METHODS: The subjects are 2,409 female flight attendants who have had medical examination and physical fitness tests at an airline medical center from January 2 to December 30, 2008. The independent variables include socio-demographic & behavioral characteristics, and medical examination results, whereas the dependent variable is their physical strength score representing their fitness level. RESULTS: Factors that affect the fitness strength score are age, flight hours per year, and fasting blood sugar level. It is found that physical fitness level is higher when the subjects are over 35, on board for over 850 hours per year and their fasting blood sugar level is over 100 mg/dL. CONCLUSION: It is concluded that for the improvement of flight attendants' health, more exercise to develop cardio-respiratory endurance and muscular strength is needed, and further study needs to be done to develop fitness enhancement programs considering flight attendants' job characteristics, working years, and flight hours per year, and programs for those returning to their workplace after a long-term leave, and new employees.

The Problem Drinking and Related Factors in Female Firefighters / 대한산업의학회지

OBJECTIVES: This study was conducted to investigate problem drinking and analyze factors associated with alcohol use among female firefighters, as well as to provide useful data for management of alcohol use by female firefighters. METHODS: The study includeed 1,587 female firefighters from throught Koea. Data were collected from June to July in 2008 using self-administered questionnaires including a general questionnaire, work related questionnaire, the Alcohol Use Disorders Identification Test (AUDIT), the Korean Occupational Stress Scale Short Form (KOSS-26), and the Center for Epidemiologic Studies Depression Scale (CESD). Among 1,263 female firefighters (75.6%) surveyed, the results of 1,084 qualified questionnaires (70.5%) were analyzed using the chi-square test, Fisher's exact test, and multiple logistic regression. RESULTS: The prevalence of problem drinking (AUDIT score > or =8) in female firefighters was 12.5%. Multiple logistic analysis showed that being single, smoking and depression were correlated with problem drinking. Single female firefighter, present smokers and individuals positive for symptoms of depression had OR values of 2.11, 17.58 and 1.76, respectively. CONCLUSIONS: Three factors were found to influnce the occurrence of problem drinking. Accordingly, smoking related education, counseling to cope effectively with depression and health promotion programs that consider psychological effects of job stress are needed to reduce work related factors that lead to problem drinking by female firefighters.

The Effects of Injury and Accidents on Self-rated Depression in Male Municipal Firefighters

OBJECTIVES: The present study aims to determine the causal relationship between self-rated depression and experiences of injury and accidents in municipal firefighters. METHODS: A panel survey of 186 municipal firefighters measured with depressive symptoms according to the Beck's depression index (BDI) was conducted. The effects of job-related injuries and accidents were evaluated using self-administered questionnaires that were taken once in a 12-month period from 2005 to 2006. Firefighters were classified into the Depression Group or Control Group based on follow-up BDI results with a cutoff level that was set to having "over mild depression." RESULTS: The depression Group was comprised of 17 (9.1%) workers, including 9 firefighters who met had sufficient BDI scores twice in the 2-year test period and newly sufficient BDI scores in the follow-up test. A significantly higher number of subjects in the Depression Group experienced injuries and accidents in the 2-year test period as compared to the Control Group (15.4% vs. 1.5%, p=0.04). Firefighters who experienced injuries and accidents in the 2-year test period had a 7.4 times higher risk of being in the Depression Group than those who had not. As compared to accidents, near-miss accidents revealed stronger risks related to being classified as in the Depression group (adjusted odds ratio [OR] = 4.58, 95% confidence interval [CI] = 1.15-18.18 vs. Adjusted OR = 4.22, 95% CI = 1.08-16.58). CONCLUSION: The above results suggest that we should establish an effective program to promote mental health for groups at high risk for self-rated depression, including persons who have experienced consecutive injuries and accidents as well as near-miss injuries.

The Reliability and Validity of the Negative Acts Questionnaire-Revised (NAQ-R) for Nurses for the Assessment of Workplace Bullying / 대한산업의학회지

OBJECTIVE: This study was conducted to assess the reliability, the validity, the psychological characteristics, and the internal structure of the Negative Acts Questionnaire-Revised (NAQ-R) for nurses for the assessment of the workplace bullying. METHODS: A total of 190 female nurses who worked in a university hospital and who had participated in an annual health surveillance program were recruited into the study. A structured questionnaire was used to evaluate each participant's workplace bullying, job stress, and psychosocial wellbeing. Workplace bullying was assessed using the negative acts questionnaire-revised (NAQ-R), job stress was assessed using the Korean Occupational Stress Scale-Short Form (KOSS-SF) and psychosocial wellbeing was assessed using the Psychosocial Wellbeing Index-Short Form (PWI-SF). Resulting answers from the questionnaires were analyzed by chi-square, ANOVA, correlation analysis, and factor analysis. RESULTS: Victims of workplace bullying of nurses in a hospital is 37(19%) based on operational bullying criteria. The Cronbach's alpha for the negative acts questionnaire-revised (NAQ-R) is 0.9260. By exploratory factor analysis, we conclude that 3 factor are most relevant. Criterion validity was satisfied with that a negative acts questionnaire-Revised (NAQ-R) resulting in a statistically significant and positive relationship with PWI-SF , construct validity was satisfied with that NAQ-R has statistically significant and high positive correlation with the occupational climate of the KOSS results. CONCLUSIONS: The negative acts questionnaire-revised (NAQ-R) is a reliable and valid tool for the assessment of workplace bullying in the hospital nurse. By using this tool, we can imply the prevalence of and the condition of workplace bullying among the nurse.

Decision Tree of Occupational Lung Cancer Using Classification and Regression Analysis

OBJECTIVES: Determining the work-relatedness of lung cancer developed through occupational exposures is very difficult. Aims of the present study are to develop a decision tree of occupational lung cancer. METHODS: 153 cases of lung cancer surveyed by the Occupational Safety and Health Research Institute (OSHRI) from 1992-2007 were included. The target variable was whether the case was approved as work-related lung cancer, and independent variables were age, sex, pack-years of smoking, histological type, type of industry, latency, working period and exposure material in the workplace. The Classification and Regression Test (CART) model was used in searching for predictors of occupational lung cancer. RESULTS: In the CART model, the best predictor was exposure to known lung carcinogens. The second best predictor was 8.6 years or higher latency and the third best predictor was smoking history of less than 11.25 pack-years. The CART model must be used sparingly in deciding the work-relatedness of lung cancer because it is not absolute. CONCLUSION: We found that exposure to lung carcinogens, latency and smoking history were predictive factors of approval for occupational lung cancer. Further studies for work-relatedness of occupational disease are needed.

The Relation between Employees' Lifestyle and Their Health Status in an Electronics Research and Development Company / 대한산업의학회지

BACKGROUND: An unhealthy lifestyle is the most important cause of lifestyle-induced illness (diabetes, hypertension, liver enzyme abnormality, dyslipidemia etc.). This study was carried out to evaluate that relation between employees' lifestyle and their health status in a Korean electronic research and development company. METHODS: We conducted a descriptive cross-sectional survey. 3,041 consecutive workers in a Korean R&D company were enrolled in this study. A checkup list for the health examination (from the National Health Insurance Coperation), which contained the information on the lifestyle, and the results of the health examination, which contained information on the body mass index (BMI), systolic blood pressure (SBP), and diastolic blood pressure (DBP), and liver function tests (LFT, AST, ALT, gamma-GTP) and cholesterol profiles (total cholesterol, TG, HDL, LDL) were done for all the subjects. We evaluated the health profile as normal or abnormal. Statistical analysis of the health profiles and the lifestyle of the employees' was performing by using multiple logistic regression analysis. RESULTS: The prevalence of 'excessive alcohol drinking' was 52.9% (n=1,610), that for 'lack of exercise' was 86.2% (n=2,662), that for 'meat eating' 12.2% (n=370) and that for 'current smoker' was 31.3% (n=952). According to results of health examination, the prevalence of obesity was 27.1% (n=824), hypertension was 7.1% (n=215), diabetes was 1.0% (n=30), abnormal LFT was 15.4% (n=469) and dyslipidemia was 18.7% (n=569). On multiple logistic regression analysis of the health profile and lifestyle, 'meat eating' was related to obesity, hypertension, abnormal LFT (ALT, gamma-GTP), dyslipidemia (LDL). 'Excessive alcohol drinking' was related to obesity, hypertension, abnormal LFT (gamma-GTP). 'Lack of exercise' was related to dyslipidemia (HDL). 'Current smoker' was related to obesity, diabetes, abnormal LFT (ALT, gamma-GTP), and dyslipidemia (TG, HDL) with statistically significance. CONCLUSIONS: For workers in the R&D company, an unhealthy lifestyle (such as diet, alcohol drinking, lack of exercise and smoking) were related to obesity, hypertension, diabetes, abnormal LFT and dyslipidemia. Therefore health promotion is necessary for the young employees of an Korean R&D company.

Lifestyle and Metabolic Syndrome among Male Workers in an Electronics Research and Development Company / 예방의학회지

OBJECTIVES: The objectives of this study were to determine the relationship between lifestyle-implementation and metabolic syndrome in an electronics research and development company, and to provide a foundation for health providers of health management programs for setting priorities. METHODS: From July 1 to July 16, 2008 we carried out a descriptive cross-sectional survey. Consecutive workers of one R & D company in Seoul, Korea (N=2,079) were enrolled in study. A checklist for lifestyle (from the National Health Insurance Corporation) consisted of questions regarding diet, drinking, smoking and exercise. After the survey, researchers obtained data from health profiles for metabolic syndrome(waist-circumference, triglycerides, HDL cholesterol, blood pressure and fasting blood sugar level). Lifestyle was recorded as good or not good. Statistical analysis of metabolic syndrome and the lifestyle of subjects was done using multiple logistic regression analysis. RESULTS: The prevalence of metabolic syndrome in our study gropu was 13.3% (N=277). After adjustment for age, the adjusted odds ratios (odds ratio, 95% confidence intervals) for metabolic syndrome increased in proportion to the number of bad habits: two (1.72, 1.23-2.44), three (2.47, 1.73-3.56), and four (3.63, 2.03-6.34). Relative to subjects eating both vegetables and meat', the OR for 'meat' eaters was 1.66 (1.18-2.31). Compared with 'non-smokers and ever-smoker', the OR for 'current-smoker' was 1.62 (1.25-2.10). Compared with 'Healthy drinker', the OR for 'unhealthy drinker' was 1.38 (1.05-1.83). CONCLUSIONS: Poor lifestyle was associated with an increased likelihood of metabolic syndrome. These findings suggest that lifestyle-based occupational health interventions for young employees should include a specific diet, smoking cessation, and healthy-drinking programs.

The Relationship between Job Stress and Liver Dysfunction among Male White-Collar Workers / 대한산업의학회지

OBJECTIVES: We wanted to investigate the relationship between job stress and liver dysfunction in Korean male white collar workers. METHODS: A total of 700 male white collar workers who worked at one electronic institute and who participated in an annual surveillance program were recruited: 664(94.9%) workers were initially recruited and the data for 36 workers was excluded due to poor responses and a past history of liver disease. The questionnaire survey included the participants' general characteristics, the job-related factors, the health-related behaviors and job stress. Job stress was assessed using the Korean Occupational Stress Scale-Short Form (KOSS-SF). We merged the job stress data with the individual liver function results by conducting annual surveillance. Multiple logistic regression analysis with adjusting it for the confounding variables, including alcohol drinking and the body mass index (BMI), was used to evaluate the relationship between job stress and liver dysfunction. RESULTS: After adjustment for the confounding variables, the proportion of liver dysfunction cases was significantly higher in the groups with a high level of job stress, as assessed by the 'job demands and total score'. After conducting a stratified analysis with considering alcohol drinking and the BMI, the prevalence odds ratio of liver dysfunction was higher in the groups with a high level of job stress, as assessed by the 'job demands and total score'. CONCLUSIONS: The results of this study suggest that the level of job stress (and especially that assessed by the job demands and total score) is related to liver dysfunction. Thus, further preventive efforts and studies are needed to reduce job stress and address liver dysfunction.

The Relationship between Job Stress and Liver Dysfunction among Male White-Collar Workers / 대한산업의학회지

OBJECTIVES: We wanted to investigate the relationship between job stress and liver dysfunction in Korean male white collar workers. METHODS: A total of 700 male white collar workers who worked at one electronic institute and who participated in an annual surveillance program were recruited: 664(94.9%) workers were initially recruited and the data for 36 workers was excluded due to poor responses and a past history of liver disease. The questionnaire survey included the participants' general characteristics, the job-related factors, the health-related behaviors and job stress. Job stress was assessed using the Korean Occupational Stress Scale-Short Form (KOSS-SF). We merged the job stress data with the individual liver function results by conducting annual surveillance. Multiple logistic regression analysis with adjusting it for the confounding variables, including alcohol drinking and the body mass index (BMI), was used to evaluate the relationship between job stress and liver dysfunction. RESULTS: After adjustment for the confounding variables, the proportion of liver dysfunction cases was significantly higher in the groups with a high level of job stress, as assessed by the 'job demands and total score'. After conducting a stratified analysis with considering alcohol drinking and the BMI, the prevalence odds ratio of liver dysfunction was higher in the groups with a high level of job stress, as assessed by the 'job demands and total score'. CONCLUSIONS: The results of this study suggest that the level of job stress (and especially that assessed by the job demands and total score) is related to liver dysfunction. Thus, further preventive efforts and studies are needed to reduce job stress and address liver dysfunction.

Effectiveness of Tailored Health Promotion Program for Reducing Cardiovascular Risk Factors in Subway Workers / 대한산업의학회지

OBJECTIVES: This study explores the effects of a tailored health promotion program, in order to reduce cardiovascular risk, in areas which include hypertension, dyslipidemia, abnormal blood glucose and body mass index. METHODS: In this paper, health risk appraisal relating to lifestyle was surveyed and physical fitness, blood pressure and blood lipid profile and glucose were checked. Then, a 12 week tailored health promotion program with 40 subway workers of Seoul was conducted. The Tailored health promotion program included a smoking cessation program, drinking restriction, diet, exercise prescription and a stress management program. RESULTS: The number of subjects engaging in regular exercise increased from 42.5% to 100%, and the number of smokers reduced from 72.5% to 60%, and 12.5% of contemplate stage was shift to action stage. The mean level of drinking per day, significantly decreased from 34.9 g to 24.2. The body mass index, systolic blood pressure, total cholesterol, triglyceride, and Fasting blood glucose significantly decreased after the intervention program. In addition the tailored health promotion program resulted in a significant reduction in two factors for the cardiovascular high risk group, hypertension above 140 mmHg in systolic blood pressure and dyslipidemia above 200 mg/dl in triglyceride. CONCLUSION: In this paper, it is demonstrated that the tailored health promotion program,, including the smoking cessation program, drinking restriction, diet, exercise prescription and stress management program, resulted in effective reduction in cardiovascular risk factor. Therefore associated workplace tailored health promotion programs relating to specific individual risk factor, should be developed and implemented.

Selection of a High Risk Group and the Effectiveness of an Exercise Program on Musculoskeletal Symptoms in Small and Medium Sized Enterprises / 대한산업의학회지

OBJECTIVES: This study was conducted to provide data for the establishment of a practical and the effective exercise program for managing the musculoskeletal symptoms of workers who are employed in small and medium sized enterprises. METHODS: The risk factors related to musculoskeletal disease management were chosen according to the relevant literatures, and were based on advise from experts on the Delphi method. Questionnaires on selected risk factors (with a 5-point Likert scale) were given to 785 subjects who worked in small and medium sized enterprises. The subjects were then classified in the risk group when they had the symptoms and recorded at least 3 points. From those subjects in the risk group, those who had both work-related factors and general characteristics factors (with an average of at least 3 points) were further classified as the high risk group. We performed a 12-week musculoskeletal exercise program for the low and high risk groups to analyze their changes in symptoms and complaints in order to estimate the effectiveness of the exercise program. RESULTS: Out of 785 subjects, 454(57.8%) were in the risk group of musculoskeletal diseases and 121(15.4%) were in the high risk group. According to multiple logistic regression analysis of the factors for the musculoskeletal symptoms in the low risk group, the significant risk factors were sex and personal disease related with musculoskeletal disease, while the risk factors in the high risk group were age, sex, and personal disease related with musculoskeletal disease. After the 12-week exercise program was performed by the low risk group, the number of musculoskeletal symptom complaints in the control group did not significantly changed, whereas for the intervention group, the number of musculoskeletal symptom complaints significantly declined for all parts of the body. After the 12-week exercise program performed by the high risk group, the number of musculoskeletal symptom complaints in the control group was significantly enhanced for the arm and elbow parts. In the intervention group, the complaint rate for musculoskeletal symptoms significantly declined only for the low back. CONCLUSION: The musculoskeletal symptoms were significantly improved by the exercise program in the low risk group, but not in the high risk group. It is suggested that control measures on administrative and/or work related factors, in addition to the exercise program should be considered simultaneously for the control of musculoskeletal symptoms in groups at high risk of musculoskeletal disease.

Predictors of Return to Work in Occupational Injured Workers / 대한산업의학회지

OBJECTIVES: In order to obtain information useful in setting up occupational rehabilitation programs, an evaluation was conducted to determine predictive factors of workers' return to work after an occupational injury. METHODS: 13, 903 records of registered occupationally injured cases identified to have received disability compensation in 1998 were collected from the 36 branch of Korean Labor Welfare Corporation(KLWC). Through simple systematic sampling, a total of 3, 658 cases were selected as final subjects. Status of return to work, general characteristics, workplace characteristics, disability characteristics and disability outcome characteristics were collected from the KLWC and National Health Insurance Corporation records(NHIC). For statistical analyses, chi-square test and stepwise multiple logistic regression analysis were applied using the SAS software package program. RESULTS: Negatively affecting significant predictive factors for return to work were included the female gender, age of 50 years or older, 6 month or less of work duration, 1 or less family dependents, workplace with 200 or less employees, electric, gas, waterwork companies, foot injuries compared to finger injuries, fall from elevation, high degree of disability claims(1~4 grade), and period of medical care more than 181 days. CONCLUSIONS: The results suggest that the poor rate return to work in occupationally injured workers' is particularly affected by female gender, older-aged employees, and workers employed by electric, gas, waterwork companies. Also, it was more difficult to return to work for workers who received injuries from a fall from elevation and who had longer period of medical care(more than 181days). It is strongly recommended that more efficient and systematic occupational rehabilitation programs be set up, taking into consideration the above mentioned factors.

Health Behavior Practices and Needs for Health Promotion Program According to Shift Work Pattern in Subway Workers / 대한산업의학회지

OBJECTIVES: To determine the health behavior practices and needs for health promotion in shift work pattern in subway workers. METHODS: Among 789 male subway workers divided into four groups, 191 day time workers, 187 station service men (3 groups, 2 turns), 204 rolling stock inspectors (3 groups, 2 turns) and 207 train operators (8 groups, 5 turns), we surveyed the health behavior and needs for health promotion by questionnaire. RESULTS: For obesity, blood pressure and total cholesterol, day time workers had the highest levels, while train operators had higher diseases of the liver and stomach than others. The station service men had the highest smoking rate and daily smoking amount. More than 80% of the respondents consumed alcohol, and the drinking amount was highest among the day time workers and the 8/5 shift train operators. Eighty-two percent of the station service men had irregular eating habits and 17.7% did not have any breakfast. In health promotion activities, exercise and restriction of one's favorite(smoking or drinking) were most preferred in the four groups of respondents. The priority of needs and participation for health promotion program was exercise programs, followed by stress management, cancer prevention program, weight control program, anti-smoking campaign, high blood pressure control program, and abstinence/moderation in drinking. CONCLUSION: As the health behavior practices differed relative to shift work patterns, it was suggested that a comprehensive health promotion program according to shift work pattern should be planned and implemented among subway workers.

Stress Related Factors of Physically Disabled Workers in Manufacturing Industry / 대한산업의학회지

OBJECTIVES: This study was performed to measure the stress level of physically disabled workers, and to investigate the relationship between the stress dimensions and stress inducing factors of physically disabled workers in the Korean manufacturing industry. METHODS: The sample used in this study consisted of 341 physically disabled workers who had been working at companies in Seoul, Inchon, and Gyung-gi provinces. The Psycho-social Well-being Index (PWI), a modified version of Goldberg's 60-items of General Health Questionnaire (GHS), was used to measure the stress level. The following independent and moderate variables were designed for the same purpose. The independent variables were general and disability characteristics, workplace-related characteristics, and job stressor of the respondents. The other variables included organization-related stressors (social and family support) and person related stressors (needs and values, type A behavior pattern, locus of control and demographics), self-esteem and coping strategy. The collected data were analyzed using SAS version 6.12 program. RESULTS: Multiple logistic regression analysis showed that the significant variables on the stress level of physically disabled workers were poor self-perceived health status, low self-esteem, absence of regular exercise, physically disabled condition affecting work performance capability, dependent mobility at home, interpersonal conflict, role conflict and A type behavior pattern. CONCLUSIONS: The results of this study suggest that appropriate health promotion program should be established and provided for reducing the stress of physically disabled workers in the manufacturing industry. In addition, various vocational programs for decreasing interpersonal and role conflicts should be developed.

An Evaluation of the Ventilatory Function in Shipyard Welders Using the Lifetime Cumulative Exposure to Welding Fumes / 대한산업의학회지

Objectives:This study was conducted to evaluate the ventilatory function in shipyard welders using the lifetime cumulative exposure to welding fumes. METHODS: Ventilatory function tests were performed on 241 male welders at one large shipyard,exposed to welding fumes for over five years,and was compared to 80 male control subjects. Ventilatory function indices, such as forced vital capacity(FVC), one-second forced expiratory volume(FEV 1), ratio of FEV 1 to FVC(FEV 1%), maximal mid-expiratory flow(MMF), peak expiratory flow rate(PEFR)and maximal expiratory flow at 50 and 75% of expired FVC(FEF50 and FEF75), were obtained by analyzing forced expiratory spirograms and maximal expiratory flow-volume curves that were simultaneously measured by an Impulse ocillometry(IOS)program in the standing position. RESULTS: FEF50 and FEF75 expressed as a percentage of the predicted values were significantly lower in the exposure group than in the controls, and the MMF tended to decrease.The means of all the ventilatory indices,expressed as percentage of the predicted values, were not significantly increased at the current exposure levels. The MMF, FEF50 and FEF75, expressed as a percentage of the predicted values, were significantly decreased with an increase in exposure duration.Only the FEF75 , expressed as a percentage of the predicted value, was significantly decreased with an increase in the cumulativeexposure to welding fumes(C1). The FEF75, expressed as a percentage of the predicted value, was significantly decreased with an increase in the cumulative exposure to welding fumes(C2). The above parameters were calculated to consider the current exposure level, exposure duration, application of the ventilatory system, production rate, personal protection evice, electrode and welding wire. The MMF and FEF50, expressed as a percentage of the predicted value, tended to decrease. The proportion of workers with abnormal MMF, FEF50 and FEF75 were significantly increased with an increase in the cumulative exposure to welding fumes(C2). CONCLUSIONS: These findings suggested that the MMF, FEF50 and FEF75 are sensitive and practical indices for the evaluation of the ventilatory function of workers exposed to welding fumes, when the lifetime cumulative exposure(C2) is considered as a factor affecting exposure.

Analysis of Factors Associated with the Workers' Health Status Using Periodic Health Examination Data by Size of Enterprises

This study was conducted to determine whether the size of an enterprise can make a difference to workers' health and to examine those factors, which influence workers' health. The subjects of this study included 26,324 workers employed in manufacturing industry who received medical examinations at the Industrial Health Center at Yonsei University in 1995, 1996 and 1997. Medical examination data were used as a measure of health. Each enterprise was classified by size into three categories: Small scale enterprises (SSE) that employ no more than 50 regular employees; middle scale enterprise (MSE) that employ from 50 to 300 regular employees; and large scale enterprise (LSE) that employ more than 300 regular employees. Health conditions, according to the size of the enterprise, were determined by comparing prevalence rates, and direct standardization methods were used based upon the Korean population, as a standard population, in order to adjust for differences in population structure. 1. The findings of the medical examinations showed that, the prevalence rate in SSEs was higher than in MSEs or LSEs, but that this relationship was reversed after standardizing for sex and age. 2. Logistic regression analysis showed that, although subjects of advanced age, prolonged work history, and male gender had higher risks of disease, the size of the enterprise had no significant effect upon these risks.

Effects of Sociodemographic Factors on the Stage of Behavior Change Among Employees of Small to Medium Sized Enterprises / 대한산업의학회지

OBJECTIVES: This research attempts to investigate the relationship between health risk factors and workers'behavioral changes based on individual worker's characteristics to allow the development of more effective health promotion programs in businesses places. METHODS: A questionnaire survey was conducted with 282 workers employed in small to medium sized enterprises in the Kyong-in area of Korea. The questionnaire was composed of general characteristics, a health risk assessment and an evaluation of the stage of behavior change for health promotion strategy in the workplace. RESULTS: The health risk assessment revealed that 65.7 % of male workers smoke, 70.5% of male workers do not exercise on a regular basis, 86.1 % of female workers do not exercise at all, and 78.6 % of male workers and 50 % of female workers drink alcohol. In addition, the survey identified that 29.5% of male workers are addicted to excessive drinking, as are 11.1% of female workers. Based on the four stages of behavioral changes that lead to health, the pre-contemplation stage, contemplation stage, action stage, and maintenance stage, 40.5 %, 23.7 %, 12.1 % and 23.7 % of workers are in these stages, respectively, with regards to quitting smoking. As for regular exercises, 18.4 %, 37.6 %, 17.7 %, and 26.3 % of workers belong to each stage, respectively. As for moderation in drinking, 20.9 %, 15.4 %, 10.0 %, and 53.7 % are in each stage, respectively. The rate of health managers in the active stage of quitting smoking is significantly higher than that of general workers. Among the workers who do not exercise on a regular basis, workers over 50 years-old and blue color workers are more common in the precontemplation stage than any other worker groups. CONCLUSIONS: The results of this study suggest that the stages of behavioral change vary with worker characteristics. An awareness of the effects of the high risk factors is essential for promoting workers'attendance in health promotion programs.

Factors Affecting on the Quality of Life in Stroke Patients under Rehabilitation and Family Caregivers

OBJECTIVE: To analyze the factors affecting on the level of the quality of life of stroke patients and their family caregivers. METHOD: Among the stroke patients receiving rehabilitation treatment at forty three out patient clinic in university hospitals, 289 stroke patients who scored over 24 out of 30 points in MMSE-K and their family caregivers were interviewed using questionnaires. RESULTS: The main contributory variable on the quality of life (QOL) of caregivers was the socio-demographic factor and QOL of caregivers was improved with decreasing age, the higher level of education, the less burden of care and the better condition of patient. High correlation coefficients were showed between QOL of stroke patients and ADL, QOL of caregivers and burden of care, and the burden of care and the neurological impairment. The main contributory variable on the QOL of stroke patients was clinical characteristics factor and QOL of stroke patients was improved with increasing the levels of cognitive function and ADL performance, decreasing the level of neurological impairment, the more social support from friends and the less burden of caregivers. CONCLUSION: In order to improve the QOL of stroke patients, not only patients' physical factors, but psychological factors, socio-demographic factors and QOL of caregivers should also be considered.

Relationship between Malondialdehyde in Renal Cortex and Urinary NAG Activity of Rats exposed to Cadmium

BACKGROUND: To investigate the relationship between malondialdehyde in renal cortex and Urinary NAG activity of rats exposed to cadmium. METHODS: Rats were treated with a single intraperitoneal injection of cadmium (as CdCl2, 1 mg/kg) for cadmium-treated group and 24-hour urine were obtained prior to sacrifice on days 1, 2, 4, 8 and 16 (N=10 per each group), respectively. The concentration of malondialdehyde by thiobarbituric acid reaction and cadmium were measured in the homogenates of renal cortex. Nephrotoxocity indices such as N-acetyl--D-glucosaminidase (NAG) activity, total protein, and 24 hours urine volume, and cadmium concentration were measured in the urine. RESULT: The cadmium injection caused significant increase of cadmium concentration in the renal cortex on days 1 and 2, and in urine on days 1, 2 and 4. NAG activity and total protein concentration in urine were significantly increased on days 1, 2 and 4, and on days 1, 4 and 8, respectively. The peak values of NAG activity and total protein in urine were observed on days 1 and 4, respectively. Significant decrease of 24 hours urinary volume was induced on day 1. These results indicated that cadmium induced acute nephrotoxicity in the rats. Urinary NAG activity was changed earlier and at a higher rate than urinary total protein, which suggest that NAG activity is a more sensitive biological index in terms of early diagnosis of cadmium-induced nephrotoxicity. Renal MDA concentration was significantly increased on day 2 and on day 4, and on day 8, MDA concentration and nephrotoxicity indices except urinary total protein were returned to control level. CONCLUSION: Based on the results obtained as above, it was concluded that the malondialdehyde in renal cortex, product of lipid peroxidation was related with the changes of urinary NAG activity indicating nephrotoxic injury.