Background
: Recently the Korean society has been challenged with the rapid growth of obese popuation due to the improved socioeconomic status and lifestyle changes over the past decades. Not only has obesity been known as one of major risk factors for various diseases including cardiovascular diseases(e.g. hypertension, coronary heart disease and stroke) and diabetes mellitus, but it has also increased the death from obesity-related diseases. it has been required, however, to establish our own obesity criteria adjusted for Korean since much difference is expected to exist in the degree of obesity between white and Asian people. Therefore, this study was designed to provide with primary data to help establish new criteria through identifying the distribution of Body Mass Index(BMI), and then analyzing its relation with some obesity-related diseases.

Methods : This study calculated BMI and related it to some obesity-related diseases by analysing data from 1995 National Health Interview Surveys, in which a random sample of 5,750 Korean at the age of 15-69 had self-reported their heights, body weights and diagnoses with obesity-related diseases by physicians. Variables under consideration include potential risk factors (e.g. alcohol intakes, smoking, exercise, etc.) as well as demographics of the sample population.

Results : Average BMI(kg/M²) were 22.6±2.6 for male and 21.7±4.8 for female(mean±SD), which increased in direct proportion to the increase of age until the age reached the group of 40-59, and then followed by the inverse in its relation with the age at 60 and over. It was revealed, however, that prevalences of obesity-related diseases such as hypertension, diabetes mellitus etc. were the highest among the population group with their BMI of 23.8~35.6. In short, this study identified the proportional relation of BMI with the prevalence of obesity-related diseases.

Conclusion : In this study, the prevalence for hypertension and diabetes mellitus was shown to be higher than the average among population with their BMI of 21.9~23.8, whose figure is much lower than both 26.4, the value of the 90th percentile proposed in MONICA project and 25, the current WHO criteria of obesity. However, a Japanese study reported that the health risk began to increase at the BMI of 23 with risks for obesity-related diseases dramatically increased at the BMI of 26-27 and over, and concluded that because Asian has more body fats accumulated within the upper body part compared with the white, the Asian persons are more obese, though less in terms of BMI, than the white. Therefore, future works should be focused on establishing our own criteria for obesity with health risks through determining the association of BMI with prevalence of various diseases in Korea.

Background
: In Korea, there were many socioeconomic changes under the IMF management system. Therefore we assumed that the stress levels increased. This study was done to investigate the changes in people's stress, health behaviors, symptoms, and coping responses which might be affected by socio-economic changes during the IMF crisis with in 1 year.

Methods : In September, 1998, we sent questionnaires to a total of 560 persons who were over 18 years old and lived in Changwon city. We chose 359 subjects who completed the survey. Assuming that the stress of one's own marriage was 50 points, we asked them what degree of stress was the previous year and after August of 1997. Also, we asked them the estimate how much degree of stress had changed based on the 17 factors of life events according to Likert 5 points scale. Specifically, we investi-gated on how health behaviors were changed, how people responded to stress by using 19 coping potions of Billing and Moos, and how the 20 symptoms were changed.

Results : 71.7% of subjects replied that income was within 1 year. The amount of stress was in-creased by 13.2 points compared to the stress previous year. The levels stress in men increased significa-ntly more than in women(P=0.003), but there were no significant differences in terms of marital status, education, and age. With respect to the change of healthy behaviors, there was a tendency that the amount of exercise decreased significantly in subjects who had more stress(P=0.020). But there was no significant difference in the amount of smoking and drinking, in the frequency of drinking, sleeping time, and the regularity of eating. The health behavior score, the number of positive health behaviors, was significantly changed to negative in those whose stress increased(P=0.015). There was a tendency that the frequency of 15 symptoms among 20 symptoms significantly increased in those whose stress in-creased. Also, those whose stress increased significantly used more avoidant coping responses(P=0.007).

Conclusion : In this study, we found that those whose stress levels increased within 1 year compared to the year before up to September of 1987, had their health behaviors significantly deteriorated, and had more symptoms with avoidant coping responses. In conclusion, we suggest that those whose stress levels increased should be guided to promote good health behaviors, to use active coping responses rather than avoidant coping responses, and should be given more social support.

Background
: Dietary intervention is important in the prevention and treatment of chronic degenerative diseases, such as diabetes mellitus, hyperlipidemia, obesity, fatty liver, cerebrovascular accident, hypertension. To contribute to the improvement of periodic health examination, we investigated the current status of nutritional screening.

Methods : We gathered information about nutritional screening and education by review of questionnaires and telephone interview with physicians and dieticians in 20 university hospitals.

Results : Nutritional screening and education was not being done in 11 out of 20 hospitals. It was done only to those who were need of in 3 hospitals. In one hospital, brief nutritional screening was carried out to all and nutritional education only to those who were in need of it. In the rest of the hospitals, nutritional screening and education was done to all.

Conclusion : Nutritional screening and education was sufficient for primary and secondary preven-tion in olny a few hospitals. Joint development of nutritional screening tools and educational materials is needed.

Background
: Stress has long been recognized as a risk factor to various disorders including peptic ulcer disease. Life events are universal which everybody experiences. This study was done to find out whether stressful life events have a role in the development and exacerbation of peptic ulcer disease(PUD) and non-ulcer dyspepsia(NUD) comparing Lee's life stress scale between patients with gastroscopically proven PUD and NUD and those of control.

Methods : On hundred twenty two patients with PUD were studied at our institution from February 1, 1997 to June 30, 1997. Patients who experienced abdominal discomfort and found to have normal or chronic superficial gastritis by gastroscopic exam during the same period were selected for NUD group. Controls were selected from asymptomatic individuals who underwent upper gastrointestinal series procedure for a health screening. Stressful life events investigated were total, positive, and negative stresses measured by Lee's life stress scale(98 items), marital status, level of education, income, occupation, religion, history of cigarette smoking, and the amount of alcoholic consumption and were compared between the three groups. The data were analyzed by one was ANOVA and chi-square test.

Results : No statistically significant difference was found in total, positive, and negative stress scores between PUD group and NUD group, although they were significantly higher in PUD and NUD groups than those of the control group(p<0.05). Also statistically significant difference in income and occupa-tion, tests and school, problems associated children and familial conflict were found between PUD group and the control group)p<0.05), as weel as between NUD group and the control group(p<0.05).

Conclusion : Stressful life events were associated with development of PUD and NUD.

Background
: One of the main objectives of medical school is to provide high-quality primary care physicians. To fulfill this objective it is increasingly important to utilize ambulatory care setting, particularly community private practice clinic for medical students' clerkship. But program evaluation of this type of clerkship is lacking. The authors intended to evaluate th e community primary care clerkship with a view to students' perspective.

Methods : We used students' and preceptors' evaluation forms with semi-structured questionnaires using 5-point Likert scale and students' essays for program evaluation. We analyzed 76 students' and 89 preceptors' evaluation forms by description, and categorized emergent themes from 89 students' essays using qualitative method.

Results : Over seventy percent of students rated overall satisfaction, achievement of knowledge, preceptors' educational effort, and practical application as excellent on the 5-point Likert scale. In the evaluation of the discussion topics with preceptors, they rated medical insurance and health care delivery system as relatively poor compared to other topics such as realities of private practice, management of private practice and equipments necessary in primary care. They understood positively the importance of patient characteristics and good patient-physician relationship in primary care, and the realities of private practice. They were also concerned about the problems of health care system and assumed a sound suspicion whether the education in medical school was practical in primary care. On the other hand, they showed ambivalence towards expressing the negative aspect of primary care in terms of the repetition of simple cases and lack of stimulation to achieve sophisticated medical knowledge.

Conclusion : Community primary care clerkship was generally satisfactory in the students' perspective, which is necessary to standardize preceptor education and establish a role model of primary care in order to provide the soil for high-quality primary care physician.

Background
: It is well known that Korea is one of the endemic areas for viral hepatitis B and those who are positive for HBsAg has been reported to be about 5-10% in Korea. Since the 1980's, research and population education for prevention and vaccination for hepatitis B were implemented in Korea. Therefore, we predicted that the positive rates of HBsAg and Anti-HBs have changed since then. Young adults are considered to be the main candidates for hepatitis B vaccination, and the change in the rate of prevalence of HBsAg and Anti-HBs has been investigated in this study.

Methods : We surveyed 1760 freshmen who were positive for HBsAg and Anti-HBs who were in 1998. HBsAg and Anti-HBs was tested by RPHA/PHA.

Results : 3760 students included 2780 males and 980 females(mean age 19.44 years). Among them, 128(3.4%) was positive for HBsAg and 2488(66.2%) was positive for Anti-HBs. The positive rate of HBsAg was 105(3.8%) and that of Anti-HBs was 1797(64.7%) among 2780 male students. The positive rate of HBsAg was 23(2.3%) and that of Anti-HBs was 691(70.5%) among 980 female students.

Conclusion : As compared with previous prevalence studies of HBsAg and Anti-HBs, the positive rate of HBsAg was decreased and that of Anti-HBs was increased. The researchers hope that farther study is necessary using wider range of subjects.

Background
: Korea is an endemic area of viral hepatitis B. In spite of the HBV vaccination program since 1983, the prevalence of HBV antigen had remained high, which was 3.9% in male, 2.7% in female in 1994. But there is no approved management guideline on isolated anti-HBc and the meaning of which is not clear except the evidence of past infection. Therefore, we tried to investigate the factors which influence th seroconversion of anti-HBs during follow-up period.

Methods : Medical records of 239 subjects with isolated anti-HBc, who visited a health promotion center from 1995 to 1997 and who were retested at least once during the 1-3 years' follow-up period, were analyzed.

Results : The seroconversion rate of anti-HBs was 45.61%(109/239) on the follow-up test. The number of newly vaccinated or non-newly vaccinated subjects during the follow-up period was 156 and 72, respectively. the seroconversion rate of anti-HBs of each group were 57.69(90/156) and 22.22%(16/72) respectively(P<0.01). The subjects without previous history of HBV vaccination was 103. Among them the seroconversion rate of anti-HBs of the newly vaccinated or the non-newly vaccinated group were 59.70%(40/67) and 22.22%(8/36), respectively(P<0.01). Sex, age, BMI, smoking, previous history of HBV vaccination did not influence significantly on th seroconversion rate of anti-HBs among the subjects with isolated anti-HBc.

Conclusion : The seroconversion rate in people with isolated anti-HBc was significantly higher in the newly vaccinated than the non-newly vaccinated regardless of the previous history of HBV vaccination in this study. In spite of the nondifferentiation of anamnestic response from primary antibody response, we can expect to benefit from HBV vaccination in those with isolated anti-HBc.