Incidence and Risk Factors for Occupational Low Back Pain Among Shipyard Workers / 대한산업의학회지

OBJECTIVES: This study was conducted to estimate the incidence rate, and to identify the risk factors for the occupational low back pain among shipyard workers. METHODS: The study subjects consisted of 9,784 workers who were employed in a ship-building industry(excluded workers who had a history of low pack pain before 1995 or did not take periodic health examination in 1995). The cases were 220 people who experienced back pain from January 1, 1996 to December 31, 1998. To assess risk factors for occupational low back pain, Cox propotional hazard model was used. RESULTS: During the recent three years from 1996 to 1998, the incidence rate per 1,000 persons was 7. 8 in 1996, 8. 8 in 1997, and 3. 1 in 1998. The main causes of work-related low back pain were sprain, strain and disc herniation. Lifting was the most common cause of back pain(35. 3%), and carrying(10.2%) and pulling(8.0%) were followed. In Cox proportional harzard model, independent risk factors for back pain were body mass index(R.R.; 1.54, 959o C.I.: 1.06-2.25), shift work(R.R.; 1.65, 95% C.I.: 1.19-2.28), and lifting heavy material(R.R. ; 3.95, 95% C.I: 2.29-6.82). CONCLUSIONS: This study suggests that the risk factors of back pain in shipyard workers were body mass index, shift work and lifting.

Effects of Job Strains on Absenteeism from Work / 예방의학회지

OBJECTIVES: The purpose of this study was to assess the relationship between job strains and absenteeism from work. METHODS: The study design was cross-sectional, and the study subjects consisted of 1,166 workers who were employed in the small-sized industries. A self administered questionnaire was used to measure the general characteristics, job characteristics(job demand, job control), and social support(coworker support, supervisor support) at work. The Job Content Questionnaire(JCQ) was used to assess job demand(2 items) and decision lattitude(10 items). Social support at work (10 items) was measured using JCQ. Sick absence was collected using self-report and were rechecked by the attendance record of their company. Odds ratios and 95% confidence intervals for the association between job strain and sick absence were estimated. The modifying effect of social support was evaluated by stratification. Logistic regression was used to estimate the relationship between job strain and sick absence. RESULTS: In the bivariate analysis, the variables related to sick absence were age, marital status, occupation, job demand. Four distinctly different kinds of level of job strain were generated by the combination of job demand and job control: low strain group, high strain group, active group, and passive group. The crude odds ratio of high job strain was 1.78(95% CI: 1.26-2.53), and those of active group and passive group were 1.33(95% CI: 1.07-1.66) and 1.13 (95% CI: 0.88-1.47), respectively. The odds ratio of high job strain after adjusting for age and occupation were still significant. The odds ratio of high job strain in low social support was 5.96(95% CI: 2.45-14.51), but that in high social support was 0.73(95% CI: 0.26-2.01). CONCLUSIONS: Job strain was associated with increased risk of absenteeism from work, and social support at work modified the association between job strain and sick absence.

Changes of Souble ICAM-1 Levels in Patients with Tsutsugamushi Disease / 대한내과학회지

OBJECTIVES: ICAM-1 has been shown to be required for leukocyte migration into inflammed area and plays a significant role in inflammatory disease including bronchial asthma, and various infectious disease such as tuberculosis and malaria. Although, the significance of soluble ICAM-1(sICAM-1) in rickettial disease has not been recognized. The present investigation was designed to evaluate the sICAM-1 levels in patients with tsutsugamushi disease, and the correlation factors between sICAM-1 level and subject characteristics including clinical and laboratory indices. METHODS: Eight normal controls and thirteen patients with tsutsugamushi disease underwent serum sampling for sICAM-1 level, which was measured by using ELISA kit. RESULTS: 1) sICAM-1 level is significantly elevated in patients group. 2) sICAM-1 level is a significantly correlation with AST level, titer of anti-tsutsugamushi antiboby, and leukocyte counts, but other factors such as age, sex, differential fraction of leukocyte, ALT, duration of fever, and total hospital day etc, are not. CONCLUSION: These results show that sICAM-1 may be a role in the pathogenesis of tsutsugamushi disease.

Evaluation of Health Exams on Local Vibration Illness among Shipyard Workers / 대한산업의학회지

A hand-arm vibration syndrome, local vibration illness, occurs in some workers who use hand held vibration tools. It consists of white fingers, diffusely distributed finger neuropathy, pain in the hand and arm, and a small excess risk of osteoarthritis. This study is aimed to identify effective methods to confirm local vibration illness among various health exams, which are mentioned in worker's special health exam regulation. In addition, this study is aimed to quantitatively assess the daily vibration exposure level as a major determinant of vibration illness. The subjects, 46 vibration workers, were selected according to the results of the first special health exam about vibration hazards at shipbuilding industry in 1997. They all had experiences of work related blanching of fingers. Fifteen controls, who had no vibration exposure at all, were also recruited to compare their test results with the results of vibration workers. We adopted 1 subjective and 6 objective tests to evaluate the effectiveness and feasibility for confirming local vibration illness. These tests were history taking of subjective symptoms according to the Stockholm classification, checking blood pressure of finger, checking grasp power, checking finger skin temperature, nail-bed pressing test, vibration perceptional threshold test, and skin prick test for pain perception. Among these, checking skin temperature, nail-bed pressing test, and vibration perception test included cold water provocations. We also estimated some vibration exposure levels of hand held vibration tools by using previously published data from one automobile company. In conclusion, history taking of subjective symptoms according to the Stockholm classification, nail-bed pressing test, and vibration perceptional threshold test were discovered to be effective to diagnose local vibration illness. Furthermore, vibration perceptional threshold on right fingers showed a dose-response relationship to daily vibration exposure levels. The parameter beta was 0.0005(+/-0.0002), and statistically significant by REM (random effects model).