Colorectal Neoplasm in Asymptomatic Average-risk Koreans: The KASID Prospective Multicenter Colonoscopy Survey

BACKGROUND/AIMS: The incidence of colorectal cancer is increasing in Korea, but the epidemiology of colorectal neoplasm is not clearly defined. We aimed to elucidate the prevalence of colorectal neoplasm in average-risk Koreans and explore the underlying risk factors. METHODS: A large-scale, multicenter, prospective study was conducted. Of the 19,460 subjects who underwent colonoscopy at 11 university hospitals, we analyzed 3,951 consecutive asymptomatic adults with no risk factors for colorectal cancer. RESULTS: The subjects were aged 52.1+/-11.6 years (mean+/-SD) and 60.1% of them were men. The prevalences of colorectal neoplasm and advanced neoplasm were 33.3% and 2.2%, respectively. The prevalence of a neoplasm increased with age (trend: p<0.001) and was higher in males (p<0.001). The prevalence of a proximal neoplasm was higher in subjects with a distal neoplasm than in those without a distal neoplasm (11.9% vs. 5.4%, p<0.001). However, 150 (52.1%) of the 288 subjects with a proximal neoplasm had no distal neoplasm. CONCLUSIONS: The overall prevalence of colorectal neoplasm in asymptomatic average-risk Koreans is comparable with that in Western countries. Being male and older are associated with a higher risk of colorectal neoplasm. Over half of proximal neoplasms are not associated with any distal sentinel lesions.

Clinical Significance of Screening Colonoscopy in Elderly: A KASID Multi-center Study

BACKGROUND/AIMS: Currently, screening colonscopy is widely performed in the medical field. The initial time of screening is recommended at an age of 50 years, but the age to cease screening is unknown. Accordingly, we have investigated the diagnostic yield of colonoscopy according to indications in the elderly, and we evaluated if screening colonoscopy is useful in the elderly. METHODS: We recruited asymptomatic individuals undergoing screening colonoscopy according to age (2830 subjects aged 50-74 years and 111 subjects > or =75 years-old), The colonoscopy findings of the study subjects were compared. In addition, colonoscopy findings of asymptomatic subjects more than 75 years-old were compared with the findings of symptomatic subjects with the same age. RESULTS: The yield for overall neoplasia and advanced adenoma was higher in the group of subjects > or =75 years-old than in the 50-74 years age group (overall adenoma: 49.54% versus 24.98%, p or =75 years-old than in symptomatic subjects > or =75 years-old (49.54% versus 28.19%, p or =75 years-old. The lack of a decline in the frequency of adenoma, including advanced adenoma, justifies continuing screening colonoscopy in the elderly.

Analysis of Sufficient Conditions in Approving Cere b rovascular and Cardiovascular Disease as Occupational Disease / 대한산업의학회지

OBJECTIVES: This study was performed to analyze the factors that affect the decision to approve workers compensation claims for cerebrovascular and cardiovascular diseases and to analyze the worker characteristics. METHODS: Three hundred, sixty-nine cases were collected based on the workers compensation records of three Seoul and Incheon Regional centers of the Labor Welfare Corporation between 1998 and 1999. They contained the general characteristics, injury information and past medical histories. The x2-test and logistic regression were performed to investigate the factors affecting the approvals. Seventy-two survivors were surveyed by telephone for job stress. Job stress was surveyed in three parts: job demands, decision latitude and personal free time. RESULTS: Of the cases, 167 obtained approval from the Corporation; the others did not. Regardless of approval, 62% of all subjects had more than one of the cerebral and cardiovascular risk factors. Especially, 53.9% of subjects had hypertension. According to the logistic regression, the fatal cases had a higher approval rate (OR=26.4, CI=9.13-76.22). The cases with working condition change (OR=6.5, CI=3.45-12.07), accidents on worksite (OR=4.9, CI=2.39-10.07), female (OR=4.0, CI=1.21-13.3), accidents at night duty (OR=2.9, CI=.156-5.39), cases occurring on duty (OR=.25, CI=1.34-4.72) and cases without past disease history (OR=1.8, CI=1.02-3.36) also had higher approval rates. Telephone survey found that the approval rate increased with decreasing freedom of personal time schedule. However, the logistic regression revealed that job stress didnt affect the approvals. CONCLUSION: To prevent cerebrovascular and cardiovascular diseases, the most important aspect is to control hypertension which is the most common risk factor among the victims. Moreover, job stress and over working should be considered in the just approval of the workers compensation claims.

Pain Related Factors in Upper Extremities Among Hospital Workers Using Video Display Terminals / 대한산업의학회지

OBJECTIVES: This study was designed to quantify symptoms in the upper extremities and to identify the pain related factors among hospital workers using video display terminals. METHODS: The subject-group consisted of 138 employees working at a hospital using video display terminals. A structured questionnaire was used to estimate the participants' general characteristics, and job contents. Job stress was measured using Karaseks JCQ(Job Content Questionnaire). Pain in the upper extremities was identified according to the NIOSH symptoms survey criteria. Quantification was measured using Kim Chul's method. Pearson's Correlation analysis was used to identify validity in quantification. VAS(visual analog scale) was used to compare with this method. Multiple regression analyses elucidated the relationship between quantified pain and various work factors, such as job stress. Data were analysed with SAS 6.12 program. RESULTS: First, in quantification using Kim Chul's method, the correlation between modified PRS(pain rating score) and VAS was extremely high by 0.60(P<0.01), indicating the high validity of PRS. Second, the groups of high job demand, high job control, and females were related to an increased pain level. CONCLUSIONS: These results suggest that the self pain assessment method, PRS, is valuable and useful in analyzing occupational musculoskeletal symptoms. High demand, job control and gender may influence the levels of pain. Prospective studies about musculoskeletal disorder are required.

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.

Prostate Volume Variation with Age: Community-based Survey in Namhae Region / 대한남성과학회지

PURPOSE: The size of prostate increases with age, but there has been few Korean data on the prostate size in the general population. We thereby report the size of prostate with respect to age in Korean men residing in Namhae, Korea. MATERIALS AND METHODS: To determine the prostate size, 1421 men from Namhae, Korea underwent transrectal ultrasonography. Size of the prostate was estimated as a weight by the elliptical method. RESULTS: The mean prostate weight was 33.5 10.6 ml. The relationship between prostate volume and age was statistically significant in 1421 men (Pearson correlation coefficient=0.156, p=0.0001). Also, between the normal group and the groups of men with lower urinary tract symptoms (LUTS), there was significant correlation with age (Pearson correlation coefficient=0.162, p=0.0001), while results were insignificant with size (Pearson correlation coefficient= 0.170, p=0.0001). CONCLUSIONS: Size and rate of growth of the prostate were smaller compared to the Western society, nevertheless, prostate size increased with age. For accurate and reasonable age-specific size of the prostate of Korean male, more community based multicenter study will be needed with more refined measurement techniques such as step-section planimetry for the prostatic volume estimation.

Age-Specific Reference Ranges for Serum Prostate-Specific Antigen: Community-based Survey in Namhae Region / 대한비뇨기과학회지

PURPOSE: To establish the relationship between serum prostate specific antigen (PSA) concentration and age in a community-based population without clinically evident prostate cancer, a population based screening study was performed in a rural area in Southern Korea. MATERIALS AND METHODS: From January 1999 to December 1999, 1,278 volunteer men aged from 40 to 89 years in Namhae, Korea participated in a clinical examination that included a serum PSA determination (TANDEM-R assay), digital rectal examination and transrectal ultrasonography. The subjects who had clinical evidence of prostate cancer and high PSA concentration (>10ng/ml) were excluded. The PSA levels were compared with age using Pearson correlation and linear regression analysis. RESULTS: The serum PSA concentration correlated with patient age (r=0.129, p=0.001). The observed 95th percentile increased from 1.37ng/ml for subjects in the 40's to 6.18ng/ml for subjects in the 80'2. The reference range for serum PSA (95 percentile) for men in the 40's was 0.24 to 1.37ng/ml; for 50 to 59 years, 0.27 to 2.68ng/ml; for 60 to 69 years, 0.25 to 4.00ng/ml; for 70 to 79 years, 0.29 to 4.55ng/ml; and for 80 to 89 years, 0.31 to 6.18ng/ml. CONCLUSIONS: Our data showed that the serum PSA concentration directly correlated with patient age (Pearson correlation coefficient=0.129, P=0.001). Thus, rather than relying on a single reference range regardless of different age groups, it may be more appropriate to have age-specific reference ranges. Our data were lower than that of the Western data, and could provide an adjunctive information in interpreting PSA data in Korean men, especially in the elderly population.

Effects of transient threshold shift and ambient noise on sensitivity and specificity of first screening of special health examination for noise / 대한산업의학회지

OBJECT: This study was performed to increase the sensitivity and specificity for screening the examinee of second hearing test. METHODS: Study subjects were 219 workers who exposed more than average 80dB. They were taken the hearing test two times, before noise exposure and at 1 hour to 4 hours after worksite noise exposure. To investigate the ambient noise workers who were taken the hearing test in the test room which ambient noise was less than 45dB were classified Group I and the others were classified Group E. To calculate the sensitivity and specificity we made it gold standard whether worker had noise induced hearing loss. RESULTS: Difference of hearing loss between before and after noise exposure for left and right ear was 11. 4 dB and 11. 7 dB respectively at 500 Hz, 8. 7 dB and 9. 6 dB at 1, 000 Hz, 6. 3 dB and 6. 9 dB at 2, 000 Hz and 6. 9 dB and 7. 4 dB at 4, 000 Hz in Group I. That for left ear and right ear was 5.8 dB and 4.9 dB at 500 Hz respectively, 5.4 dB and 6.4 dB at 1,000 Hz, 6.3 dB and 5.3 dB at 2,000 Hz, and 5.5 dB and 5.8 dB at 4,000 Hz in Group E. The sensitivity was 100 in both Groups and the specificity was increased to 58. 3 and 71. 8 in Group I and Group 3 respectively until 10 dB was deducted from hearing level at 1, 000 Hz and 4, 000 Hz. CONCLUSION: When the screening hearing test was performed at worksite, we might deduct 10 dB from measured hearing level to increase the specificity without reduction of sensitivity.

Evaluation of Dermal Measurement for Workers in Benzidine Dihydrochloride and Benzidine Based Dye Manufacturing Factory / 대한산업의학회지

This study is performed to evaluate usefulness of dermal measurement of benzidine and benzidine based dye as one of the occupational exposure assessment method for these compounds. We selected one benzidine manufacturing factory and one dye manufacturing factory in Incheon area. Eleven workers were for benzidine manufacturing factory and twenty four for dye. We analyzed relationships among air level, amount on skin and concentration of urinary metabolites for these compounds. Airborne levels of benzidine and dye were measured by NIOSH 5509, 5013 methods. Amount of these compounds on skin was measured with skin wipe method. Concentration of benzidine metabolites in urine was measured by High Performance Liquid Chromatography after alkaline hydrolysis. The amount of benzidine on hand skin was 25.05( - 233.2) ng/ur, and the amount of the neck was 2.01 ( - 11.9) ng/cm2 in the benzidine dihydrochloride manufacturing factory. The amount of benzidine on hand and neck skin has positive correlation with concentration of urinary monoacetyl benzidine (r=0.644, p < 0.05) . The amount of benzidine based dye on hand skin was 55.75( - 457.7) ng/cm2, and the amount of the neck skin was 18( - 284.7) ng/cm in benzidine based dye manufacturing factory The amount of dye on hand and neck skin has positive correlation with concentration of urinary benzidine for dye workers (r=0.467, p < 0.05). When assessing the exposure of workers who deal with benzidine, the amount of benzidine on skin should be measured for an accurate exposure assessment.

A Post-examination Health Care Status of Workers with Noise Induced Hearing Loss in Manufacturing Factories / 대한산업의학회지

The number of workers with noise induced hearing loss which comprise 56.9% in the total number of workers with work-related diseases in Korea of 1994, are becoming in position of the most serious problem. Periodic health examination system which was introduced for health care of workers on hazardous workplace has played important role in health care and the prevention of work-related diseases. The goal of periodic health examination may be obtained when we not only discover occupational disease, but also control them effectively. To study the post-examination health status of workers with noise induced hearing loss diagnosed from 1991 to 1994 in the periodic health examination, all 154 workers in 102 manufacturing factories in Banwol and Siwha industrial complex were reviewed. ' 1. Among 154 workers, 87 workers (56.5%) were changed to different department, 67 workers (43. 5%) remained in the same department. 2. Among 102 workplaces, only 23 workplaces (22.9%) 'had changed their working environment while 79 workplaces (77.1%) did not. 3. In this study, post-examination health care of the workers diagnosed as noise induced-hearing loss had significant correlated with the presence of health care manager, Industrial Health and Safety Committee in workplace and size of industry. The improvement of working environment is also closely related with the presence of health care manager in workplace. 4. Among 154 respondents, 3 Wkers(l. 9%) had received! compensationwhile 151; workers(98.1%) did not. 5. The reasons for not requesting the compensation were that 117 workers (77.5

A Post-examination Health Care Status of Workers with Noise Induced Hearing Loss in Manufacturing Factories / 대한산업의학회지

The number of workers with noise induced hearing loss which comprise 56.9% in the total number of workers with work-related diseases in Korea of 1994, are becoming in position of the most serious problem. Periodic health examination system which was introduced for health care of workers on hazardous workplace has played important role in health care and the prevention of work-related diseases. The goal of periodic health examination may be obtained when we not only discover occupational disease, but also control them effectively. To study the post-examination health status of workers with noise induced hearing loss diagnosed from 1991 to 1994 in the periodic health examination, all 154 workers in 102 manufacturing factories in Banwol and Siwha industrial complex were reviewed. ' 1. Among 154 workers, 87 workers (56.5%) were changed to different department, 67 workers (43. 5%) remained in the same department. 2. Among 102 workplaces, only 23 workplaces (22.9%) 'had changed their working environment while 79 workplaces (77.1%) did not. 3. In this study, post-examination health care of the workers diagnosed as noise induced-hearing loss had significant correlated with the presence of health care manager, Industrial Health and Safety Committee in workplace and size of industry. The improvement of working environment is also closely related with the presence of health care manager in workplace. 4. Among 154 respondents, 3 Wkers(l. 9%) had received! compensationwhile 151; workers(98.1%) did not. 5. The reasons for not requesting the compensation were that 117 workers (77.5