The Association of Central Obesity with Type 2 Diabetes among Koreans according to the Serum Gamma-Glutamyltransferase Level: Korean Genome and Epidemiology Study / 예방의학회지

OBJECTIVES: This cross-sectional study was performed to examine if the serum gamma-glutamyltransferase (GGT) level that is within its normal range is associated with the risk of type 2 diabetes and if the association between the waist hip ratio (WHR) and type 2 diabetes is different depending on the serum GGT levels. METHODS: The study subjects were 23,436 persons aged 40 years or older and who participated in regular health check-ups at 11 hospitals (males: 5,821, females: 17,615). The gender-specific quintiles of the serum GGT and WHR were used to examine the associations with type 2 diabetes. RESULTS: The serum GGT levels within their normal range were positively associated with type 2 diabetes only in women. The adjusted odds ratios (ORs) were 1.0, 1.0, 1.4, 2.1, and 2.5 according to the quintiles of the serum GGT (p(trend)<0.01). The WHR was more strongly associated with the prevalence of diabetes among the women with a high-normal serum GGT level as compared with those with a low-normal serum GGT level (p for interaction=0.02). For example, the adjusted ORs for women with a low normal serum GGT level were 1.0, 1.2, 1.5, 2.2, and 2.4 according to the quintiles of the WHR, while those figures were 1.0, 2.4, 3.6, 5.0, and 8.3 among the women with a high normal serum GGT level. However, in men, the serum GGT was very weakly associated with type 2 diabetes and the association between the WHR and type 2 diabetes was not different depending on the serum GGT level. CONCLUSIONS: Serum GGT within its normal range was positively associated with type 2 diabetes, and central obesity was more strongly associated with the prevalence of type 2 diabetes when the serum GGT level was high-normal. However, these associations were observed only in women, which is different from the previous findings. The stronger relation between central obesity and type 2 diabetes among women with a high-normal serum GGT level can be useful for selecting a group that is at high risk for type 2 diabetes irregardless of whatever the underlying mechanism is.

Developing an Occupational Stress Scale for Korean Employees / 대한산업의학회지

BACKGROUND AND PURPOSES: Over the past three decades, numerous studies performed in Korea have reported that job stress is a determinant risk factor for chronic diseases and work disability. Every society has its own culture and occupational climate particular to their organizations, and hence experiences different occupational stress. An occupational stress measurement tool therefore needs to be developed to estimate it objectively. The purpose of this study is to develop and standardize the Korean Occupational Stress Scale (KOSS) which is considered to be unique and specific occupational stressors in Korean employees. Subjects and METHODS: Data were obtained from the National Study for Development and Standardization of Occupational Stress (NSDSOS Project: 2002-2004). A total of 12,631 employees from a nationwide sample proportional to the Korean Standard Industrial Classification and the Korean Standard Occupational Classification were administered. The KOSS was developed for 2 years (2002- 2004). In the first year, we collected 255 items from the most popular job stress measurement tools such as JCQ, ERI, NIOSH and OSI, and 44 items derived from the a qualitative study (depth interview). Fortythree items of KOSS, in the second year, were retained for use in the final version of the KOSS by using Delphi and factor analysis. Items were scored using conventional 1-2-3-4 Likert scores for the response categories. RESULTS: We developed eight subscales by using factor analysis and validation process: physical environment (3 items), job demand (8 items), insufficient job control (5 items), interpersonal conflict (4 items), job insecurity (6 items), organizational system (7 items), lack of reward (6 items), and occupational climate (4 items). Together they explained 50.0% of total variance. Internal consistency alpha scores were ranged from 0.51 to 0.82. Twenty-four items of the short form of the KOSS (KOSS-SF) were also developed to estimate job stress in the work setting. Because the levels of the subscales of occupational stress were gender dependent, gender-specific standard norms for both the 43-item full version and the 24-item short form using a quartile for the subscales of KOSS were presented. CONCLUSION: The results of this study suggest that KOSS might be an appropriate measurement scale to estimate occupational stress of Korean employees. Further and more detailed study needs to be conducted to improve the validity of this scale.

Surveillance of work-related carpal tunnel syndrome in Korea / 대한산업의학회지

OBJECTIVES: Carpal tunnel syndrome (CTS) is one of the most important work related musculo-skeletal diseases in Korea. However, there are few epidemiologic studies on the work-related CTS (WR-CTS). This study aimed to investigate the epidemiologic characteristics of WR-CTS in Korea. METHODS: Data obtained from the"CTS Surveillance System". Physician case-reports in the surveillance were used to document patterns of WR-CTS by age, gender, occupation, sign, symptom, working history. RESULTS: Six hundred and seventy-two cases of WR-CTS were ascertained. of which 314 with complete information on occupational history were analyzed. It has been estimated that as many as 72% of all CTS cases are work-related. The highest proportion of WR-CTS was observed in 'elementary occupation workers', followed by 'skilled agricultural, forestry and fishery workers'. The distributions of WR-CTS cases were similar with respect to age, obesity, and past medical history. The proportion of WR-CTS was higher in females. There was no significant difference in physical examination findings between WR-CTS and non WR-CTS cases. Repetitive work and the inappropriate hand posture seemed to be the risks for WR-CTS. CONCLUSION: WR-CTS is a significant public health problem. The CTS surveillance system is quite useful to elucidate the characteristics of WR-CTS, but it remains of limited use in targeting specific industries and occupations for intervention.

Shiftwork Duration and Metabolic Risk Factors of Cardiovascular Disease / 대한산업의학회지

AIMS: To explore the relationship between shiftwork duration and metabolic risk factors on cardiovascular disease in shiftworkers. METHODS: The study subjects comprised of 226 nurses, from a hospital, and 130 male workers, from a diaper and feminine hygienic material manufacturing firm. The mean ages of the male workers and nurses were 29 and 28.5 years, respectively. The fasting blood sugar, serum cholesterol, blood pressure, height and weight, waist and hip circumferences (only in nurses), and number of step for a shift as indices of physical activity were measured. Using the Korean version of Karasek's job contents questionnaire, the job stress was assessed. Information about the number of years worked, duration of shiftwork, and past medical and behavioral histories, including smoking, were obtained by self-administrated questionnaires. Linear regression analyses were performed, to show the relationships between shiftwork duration and metabolic risk factors, using simple and multivariate models, adjusted for age, smoking, job strain and physical activity. The following criteria were defined: hypertension as a SBP>or160 or a DBP>or=90 mmHg at least once, hypercholesterolemia, as a serum total cholesterol >or=240 mg/dl, obesity as BMI (Body Mass Index) >or=25kg/m2 and central obesity as a WHR (Waist to Hip Ratio) >or=0.85; and the logistic regression analyses, according to years of shiftwork, were performed using simple and adjusted models. RESULTS: The cholesterol and fasting blood sugar showed increasing trends, but without statistical significances, according to the increase in shiftwork duration of the male workers, although, the increases in the blood pressure and BMI were statistically significant. In the nurses, only the WHR showed a significant increase in relation to the shiftwork duration. In the logistic regression analyses, hypercholesterolemia and obesity showed significant increasing risks according to the number of years of shiftwork (OR=3.32 95%CI 1.27-8.72 and OR=3.21 95%CI 1.24-8.32 respectively) in the male workers, but hypertension showed no significance. In the nurses, only an increased central obesity was significant as a risk factor (OR=1.30 95%CI 1.05-1.62). CONCLUSIONS: These results provide evidence of the associations between shiftwork and metabolic risk factors for cardiovascular disease, although healthy shiftworker effects might exist in our cross sectional study design.

The Effect of Long Distance Air-travel on Serum Viscosity and Prothrombin Time

BACKGROUND: Economy class syndrome is medically described as deep vein thrombosis, it is worldwide issued that Long-Distance Air-Travel is a risk factor for venous thromboemborism. Some study provides evidence and theoretical explanations for the hypothesis that long-distance is a risk factor for venous thromboembolism. The purpose of this study is to provide the useful prevention of venous thromboembolism for long-distance travelers in comparison to the effect of long distance air-travel on serum viscosity and prothrombin time between flight level and ground level. METHODS: Subjects selected healthy volunteers that had no abnormal findings in evaluation (alpha2-plasmin inhibitor, plasminogen, anti-thrombin III, protein C, protein S) for hypercoagulability. 5subjects (1 male, 4 females) had a seat on economy class of ground training facility designed for flight attendant and their activities limited as possible during about 8 hours at Sep. 16, 2001. Also, 5 subjects had a seat on the economy class of Asiana Airlines (B-777) from Sydney in Australia to Seoul in Korea at Mar. 3, 2002. In the flight, Actual flight altitude was 31,000 feet, cabin altitude was 4,800 feet and cabin temperature was 25degrees C. We have investigated the serum viscosity used by viscometer and prothrombin time. These data were analyzed statistically by General linear model (spsswin ver. 10.0). RESULTS: The results showed that there were no differcence between Flight Group and Ground Group statistically. However, the serum viscosity of flight group by position was some higher than ground group but these defference was not statistically significance (P=0.419). Also, the serum viscosity of flight group by time had a decreased trend but these trend was not statistically significance (P=0.061). The prothrombin time of flight group by position was some lower than ground group but these defference was not statistically significance (P=0.472). Also, the prothrombin time of ground group by time had a decreased trend but these trend was not statistically significance (P=0.217). CONCLUSION: This study shows the prediction to venous thrombosis more closely relates to prothrombin time than serum viscosity under immobilization to healthy people on the ground environment. Exercise is more useful method than hydration to prevent venous thrombosis on the ground environment. In the flight environment, we think that hydration is also useful method to prevent venous thrombosis because of more dry environment inside flying aircraft. But, this study was decreased serum viscosity between samples according to time. I think serum viscosity can be reduced by vibration effect inside flying aircraft. Serum viscosity and prothrombin time between samples according to position were not statistically significant. I think that risk for the healthy people is poorly quantified and possibly overestimated that long-distance air-travel is a risk factor for venous thromboembolism.

The Preventive Programs for the Work-related Musculoskeletal Disorders in a Telephone Directory Assistance Workplace

OBJECTIVES: This study evaluated the effect of an in-house work-related musculoskeletal disorders (WMSDs) preventive programs in a telephone directory assistance workplace. METHODS: The subjects (N=177) were divided into four groups (nonparticipants, 41; preventive exercise, 31; self-physical therapy, 40; both, 65) by program participation type. The results of WMSDs program were obtained by questionnaire, which consisted of upper extremities'(neck, shoulder, arm, hand) symptom prevalence, self-rating symptom severity, and before-after symptom change between 1995 and 1998 data and workers'satisfaction by program participation. RESULTS: The prevalence of symptoms related WMSDs was only reduced in neck region of nonparticipants, other groups not in significant. The pain scale (5-likert) of each region was significantly decreased in neck, arm and hand of nonparticipants. In other groups, there was no significant change in the prevalence of WMSDs. The change of visual analogue scale was decreased by 21.7% in self-physical therapy group (p=0.043). The subjects mostly were satisfied with this in-house programs. Above all, preventive exercise and both program groups showed content over 80%. CONCLUSIONS: The results of before-after symptoms change was not inconsistent, but subjects were showed high satisfaction about the preventive programs. In attempts to improve the WMSDs related symptoms, the best results will be achieved with ongoing in-house preventive programs practice and periodic outcomes assessments.

The Health Promotion Behavior of Pilot and Ground Staff in A-Airlines

BACKGROUND: At present, there is close correlation between health status and lifestyle. Personal lifestyle has influence on health, disease, disorder and early death. Health promotion elements are nutrition, exercise, body weight, alcohol drinking, smoking, stress and so forth. These elements are important on physical and psychosocial well being. A good physical and psychosocial status can increase a personal ability of psychosocial activities. This study surveyed to assess healthy behaviors and to encourage pursuing more health promotion. METHODS: The subjects of this study were 91 pilots and 90 ground staffs in A-Airlines and the period of survey was from march, 2002 to June, 2002. This survey used Wilson's Fantastic Lifestyle Assessment and this assessment was designed to assess healthy behaviors. Data were collected by self-administered questionnaire including 12 items (.relationship of family and friends, activity, nutrition, smoking, toxin, alcohol drinking, sleep, seatbelt, stress, personality, insight, career satisfaction). These data were analyzed statistically by t-test. RESULTS: Mean score of this assessment is 39.16 in pilot, 31.99 in ground staff. Pilot had better healthy behaviors than ground staff in the aspect of all 12 items. Especially, Pilot had better healthy behaviors than ground staff in the aspect of relationship of family and friends, activity, nutrition, smoking, alcohol drinking (drunken amount), sleep, stress, personality, insight, career satisfaction. There were statistically significance (P<0.05). CONCLUSION: In comparing pilot and ground staff were significant difference except drug, seatbelt, frequency of drinking, which means that pilot had better healthy behaviors than ground staff. The result suggests that medical services supply pilots with more thorough and frequently periodic health education. In the future, the role of medical team needs to give a continuous health education of pilots and also, ground staff.

Correlation Between Total Cholesterol and Body Mass Index, Waist-Hip Ratio of Flight Attendants

BACKGROUND: Number of people who suffer from obesity tends to increase throughout the world. The obesity may cause various illnesses such as hypertension, diabetes, arteriosclerosis etc. However, obesity can be prevented by diet and weight control. This study is to find the relationship between severity of obesity and amount of blood cholesterol which is closely related to hypertension. There are two ways to indicate the severity of obesity; body mass index and waist hip ratio. Especially, the latter is favored for abdominal obesity. The goal of this study is to find out which method is more closely related to the serum total cholesterol. METHODS: From Oct. 1st 2000 to Sept. 30th 2001, the experiment is based on 585 people who are flight attendants in the A airline company. This study measured body mass index, waist hip ratio and serum total cholesterol against sex, age, height, and weight. We analyzed the data by t-test, analysis of covariance, Pearson correlation, multiple linear regression analysis. As a result, we will study the correlation between serum total cholesterol and age, sex, height, and weight by defining the serum total cholesterol as a dependent variable and any other variables that affect changes in the serum total cholesterol as independent variables. RESULTS: The 585 flight attendants (78 male and 507 female)were statistically analyzed. The average serum total cholesterol (ASTC) was significantly higher for male; ASTC of male was 175.67+/-30.23 and that of female was 166.37+/-25.57 (P=.011). ASTC was peak at the age group of 30s for male (177.97+/-30.54 , P=.0443), but female did not have much difference between the age group of 20s and that of 30s (166.33+/-24.54, 166.34+/-29.26, P=0.880). As a result from analyzing the relationship among the variables. ASTC and waist hip ratio were positively related for both male and female. Moreover, body mass index and waist hip ratio were also positively related for both genders. However, the relationship between ASTC and waist hip ratio for male was more closely related than for female (P=.033). CONCLUSION: Age, body mass index and waist hip ratio are positively related for both genders. Therefore, an appropriate exercise and a diet control for ages are necessary as getting older in order to prevent disease caused by obesity. Besides, serum total cholesterol for male was higher for 30s than 20s. Thus, especially, male within the age group of 30s should be alert to the obesity carefully with performing exercise regularly and diet control by lowering the intake of fat and alcohol.

Relationship between Low Back Pain and Physical Characteristics in Flight Attendants

BACKGROUND: Low back pain (LBP) is known to be the significant reason for absenteeism and can develop long-term disability. So the airline authorities have made an effort to reduce the incidence of LBP by applying their physical standards. As a LBP Prevention Program, Airline A has provided health education, counseling and physical examinations. The purpose of this study is to analyze the relationship between LBP and physical characteristics, age and work duration, and this result will provide basic information for improving the LBP Prevention Program. METHOD: The subjects were the 585 flight attendants who had undergone regular physical check-ups with Airline A Medical Center from October 2000 to September 2001. We reviewed their absence records and physical characteristics, age and work duration. These data were analyzed statistically by the t-test and Lositic regression. RESULT: The LBP history group accounted for 18% of the study group. The male LBP history group had the more thin waist than the no history group. There were no differences (P<0.05) between LBP and other male and female physical characteristics. The age and work duration of male LBP history group was lower than the no history group (P<0.05). But the female comparison revealed that only the work experience in the LBP history group was lower than the No history group (P<0.05). Waist, age, work duration was analyzed statistically by logistic regression. Only female's work experience was significant. The fewer work experience was the more LBP. CONCLUSION: The results of this study suggest LBP is associated with work experience rather than physical characteristics. This is the first step toward improving a LBP Prevention Program for the cabin crew. It will be useful to conduct another review to assess various other reasons, such as psychosocial job factors, duration of work disability and muscle strength, related to LBP.

Chromosome Aberrations and Sister-chromatid Exchanges in Workers Exposed to Mixed-organic Solvents in Shoe-making Workshops

Chromosome aberrations and sister chromatid exchanges (SCEs) in lymphocytes of peropheral blood as an indicator which could evaluate the effects of mutagenicity after in human exposure to mixed-organic solvents were measured. This study was conducted using 33 shoe making workers occupationally exposed to organic solvents and 33 unexposed control. The results were as follows. 1. The mean air concentrations of n-hexane, toluene, ethyl acetate in working environment were 9.8-14.8, 31.7-45.4 and 4.4-7.6 ppm, respectively. 2. The frequencies of chromosome aberration in exposed workers to mixed-organic solvents and the unexposed were 1.12+/-1.24, 0.36+/-0.70, respectively and their differences were statistically significant (p<0.01). However, the SCE frequencies were not statistically significant between the both groups. 3. The frequencies of chromosome aberration and SCE were no statistically differences by sex, smoking and drinking.

Pressure Threshold, Grip and Pinch Strength in Female Telephone Operators

The purpose of this study was to estimate mean pressure thresholds over several skeletal muscles, grip and pinch strengths in female telephone operators. Pressure thresholds on muscles of neck and shoulder were measured with a pressure algometer, and grip and pinch strength were measured with a Jamar dynamometer and a Jamar pinch gauge in 904 female telephone operators. The pressure threshold was highest in the supraspinatus and lowest in the cervical paraspinals. There was no statistically significant difference between right and left corresponding muscles. The mean grip strength was 22.29 kg in the right hand, 21.97 kg in the left hand. The mean tip pinch strength was 0.56 kg in the right, 0.51 kg in the left. The mean lateral pinch strength was 2.21 kg in the right, 2.12 kg in the left. The mean palmar pinch strength was 1.82 kg in the right, 1.66 kg in the left. There was no significant correlation between grip, pinch strength and age(p>0.05). There were positive correlations between height, weight and grip strength. There were positive correlations between exposure duration to visual display terminal and pinch strength.

Association between Myofascial Pain Syndrome and the Assessment of Pain and the related Function tests in female telephone directory assistance operators using BDT / 예방의학회지

The Association between myofascial pain syndrome and some tests was assessed in a cross-sectional study of 904 female telephone operators using video display terminals(VDTs). 105 cases were diagnosed as Myofascial pain syndrome with symptom questionnaire, laboratory examination and physician's physical examination and 550 controls were defined to show only musculoskeletal symptoms using NIOSH symptom criteria. Data on demographics, musculoskeletal symptom and visual analogue scale(VAS) were obtained by questionnaire. Anthropometric measurements, pressure pain threshold, Grip and Pinch strength and laboratory test were conducted. No significant difference between case and control at comparing of demographics, occupational history and body measurements were observed. But, Grip strength, pressure pain threshold and VAS showed the statistical difference between case and control. Age, pressure pain threshold of Rt. Upper trapezius and VAS were associated with myofascial pain syndrome in multivariate logistic regression analysis. This results suggest that, to diagnose of myofascial pain syndrome, the consideration of the objective aspects among patients' subjective symptom complaints through the VAS and pressure pain threshold is required.

Analysis on the Relationships among the Total Cholesterol, Fasting Blood Sugar, Hypertension and Ischemic heart disease on EKG Findings / 예방의학회지

Since the 1960's, Korea has achieved rapid economic growth, longer life expectancy, accelerated urbanization and a westernization of diet. Cardiovascular disease has become the leading cause of death; however the prevalence of ischemic heart disease(IHD) remains low. A cross-sectional multiphasic screening service for 18,426 persons aged 30 64 years in a Medical Aid Program in Kyonggi-do Province was conducted from 1991 to 1993. Total cholesterol(TC), Fasting blood glucose(FBG), blood pressure(BP), and electrocardiographic(EKG) data were collected. The result as follows; 1. On the EKG findings, the age-adjusted prevalence of myocardial ischemia and myocardial infarction was 1.45% in men and 2.06% in women. 2. The mean blood pressure was 122.9/78.8mmHg. The age-adjusted prevalence of hypertension was 11.05% in men and 9.02% in women. The prevalence of hypertension showed increasing tendency according to age increase. In all age group, the prevalence of hypertension was higher in men than women. 3. The mean total cholesterol level was 184.4mg/dl in men and 189.2mg/dl in women. The age-adjusted prevalence of hypercholesterolemia was 4.88% in men and 5.67% in women. The total cholesterol level showed increasing tendency according to age increase, except 55 64 age group in men. 4. The prevalence of hyperglycemia is 5.8%. The age-adjusted prevalence of hyperglycemia is 6.72% in men and 4.50% in women. The prevalence of hyperglycemia showed increasing tendency according to age increase. 5. On the EKG findings, the prevalence of myocardial ischemia and myocardial infarction was higher in hypertension than normal, in all age group of men and women less than 40 years-old. Only in women more than 40 years-old, the prevalence of myocardial ischemia and myocardial infarction was higher in hypercholesterolemia and hyperglycemia. Nevertheless there is not statistical association between ischemic heart disease and previous risk factors in other age group, the prevalence of myocardial ischemia and myocardial infarction was higher in hypertension, hypercholesterolemia and hyperglycemia than normal. The result of this study suggest that relationships between major risk factor of ischemic heart disease and ischemic heart disease is similar to existing theory.