The major earthquake increases cardiovascular disease during the period from night-time to morning, especially in the elderly patients living around the epicenter. Earthquake-induced stress increased BP and blood viscosity determinants, and enhanced fibrin turnover with endothelial cell stimulation in a group of hypertensive elderly subjects. Earthquake might trigger the cardiovascular events through the potentiation of these acute risk factors. Reduction of stress and related acute risk factors in this period may suppress cardiovascular deaths following a major earthquake. Further investigation of the mechanisms triggering cardiovascular events after the a major event such as a major earthquake is a necessary part of the strategy for the prevention of cardiovascular disease. J Epidemiol, 1998; 8 : 131-139.
An optimal cutoff point of expired-air carbon monoxide (Ex-CO) for detecting smokers should be determined in terms of its sensitivity and specificity and the prevalence of smoking in the target population. The purpose of this study is to determine the optimal cutoff point of Ex-CO for detecting smoking males in a Japanese community whose smoking prevalence was over 50%. Among free-living residents in a rural population, "true smokers" determined by presence of cotinine in serum were 61 % (n=94). When Ex-CO at 7 ppm or over differentiated "smokers" from "non-smokers", sensitivity and specificity for detecting smokers was 0.93 and 0.95, respectively, which comprised the best Youden's index. This setting also produced the minimum percentage of misclassified cases. In conclusion, 7 ppm of Ex-CO, which is exceptionally low value relative to the western standard, appears to be the most optimal cutoff point for a survey in a population with such high smoking prevalence. J Epidemiol, 1998 ; 8 : 140-145.
To evaluate the effects of passive smoking identified by urine cotinine on serum carotenoids and α-tocopherol, we categorized 124 residents in a rural city of Japan into 4 groups by their urine cotinine/creatinine (Cot/Cr) ratio (u.d. (undetectable); low (0-50 ng/mg); moderate (50-120ng/mg); high (>120 ng/mg)) and compared the serum carotenoids and a-tocopherol levels among these groups. We identified passive smoking by low Cot/Cr ratio level. After controlling on related factors, men with low Cot/Cr ratio showed significantly lower serum zeaxanthin/lutein levels than men with u.d. Cot/Cr ratio. The difference was still marginally significant after excluding selfreported current smokers from the low Cot/Cr group. It is suggested that low level exposure to tobacco smoke, which has been reported to be equivalent to that for passive smokers, could be associated with decreased serum zeaxanthin/lutein levels in men.J Epidemiol, 1998 ; 8 : 146-151.
A self-administered physical activity questionnaire (PA-questionnaire) was developed to assess daily energy expenditure and weekly physical activity in epidemiological studies. The Calorie Counter method (CC-method) was administered to 49 male and 32 female volunteers aged 18-64 years, on 7 consecutive days; after the measurement, the subjects were asked to complete the PA-questionnaire (validation study). The PA-questionnaire was completed by 95 males and 119 females (aged 35-73 years) twice with one-year interval (reliability study). The validation study showed that the mean daily energy expenditure estimated by the PA-questionnaire was slightly and significantly (4.5%) lower than that determined by the CC-method for males (p<0.05); while no significant difference was observed for females (p>0.05), mean weekly physical activities were similar between the PA-questionnaire and CC-method in males and females. Daily energy expenditures by the two methods strongly correlated with each other: r = 0.56 (p<0.001) in males and r = 0.67 (p<0.001) in females. Weekly physical activities by the two methods also strongly correlated with each other: r = 0.68 (p<0.001) in males and r = 0.69 (p<0.001) in females. The reliability study indicated that the Pearson's correlation coefficients between two assessments of daily energy expenditure and weekly physical activity over one-year ranged from 0.37 to 0.62 (p<0.001). These data indicate that the PA-questionnaire has adequate levels of validity and test- retest reliability in assessment of daily energy expenditure and weekly physical activity in epidemiological studies. J Epidemiol, 1998 ; 8 : 152-159.
To describe the geographical patterns and trends of macronutrient intake in Japan for the recent 20 years, we analyzed the data sets of the National Nutrition Surveys (J-NNS). First, we calculated regression coefficients for survey year by prefecture for energy, protein, fat, and carbohydrate intake. These results, however, could be affected by the changes in age and sex distributions of the survey samples. Secondly, as the food consumption data were based on household as a unit, we used proportions of the subjects who belong to age-specific groups and female subjects in a sub-sample for each prefecture in a given year for adjustment by general lineal model. As a result, 1 % increase in the subjects aged 1-4, 10-19 and 65- years and female subjects was equivalent to the changes in average energy intake by -5.88, +2.27, -1.45 and -1.62 kcal, respectively. After the adjustment for age and sex, number of significant negative coefficients among 47 prefectures decreased for energy and carbohydrate intake, and that of positive coefficients increased for fat intake. This suggested that unadjusted trend data might lead to an overestimation of decreasing trends of energy and carbohydrate intake, and an underestimation of increasing trend of fat intake in the recent 20 years. J Epidemiol, 1998 ; 8 : 160-167.
The intake of flavonoids and isoflavonoids was estimated based upon a preliminary database of 40 food items, covering at least 80% of total food consumption. Fifty volunteer women in "I- City" recorded the weight of all dietary intake for 3 days in September 1996, and received a health check-up, as well as laboratory examination. The data was analyzed in relation to the various food factors. Average daily intake per capita of flavonoids was as follows: 4.9 mg kaempferol, 8.3 mg quercetin, 1.5 mg rutin, 0.6 mg myricetin, 0.3 mg luteolin, 0.01 mg myricitrin, 0.4 mg fisetin, and 0.3 mg eriodictyol. Total intake from vegetables and fruits was less than 10 mg. 16.2 mg (range: 3.18-35.61 mg) and 23.27 mg (4.62-52.12 mg) of isoflavones, such as daidzein and genistein, respectively, were taken per day, and total isoflavone intake was 39.46 mg (7.80-87.73 mg). Chief component analysis on ingested vitamins, flavonoids and isoflavonoids was carried out. Factor 1 was mainly composed of flavonoids and antioxidant vitamins. Factor 1 was positively associated with age and the level of HDL cholesterol and negatively related to the level of triglycerides. Factor 2, which was mainly composed of isoflavonoids, was positively associated with creatinine and uric acid levels. So far, these factors did not show a significant association with bone density and other health indices, such as BMI and blood pressure. J Epidemiol, 1998 ; 8 : 168-175.
Purpose: Investigation of the etiological relationship between body fat and uterine leiomyomas. Settings: This was a case-control study. Percent body fat was measured bioelectrically with a body fat analyzer. Subjects: In Sapporo City, Japan, 100 women with uterine leiomyomas (pathologically diagnosed) and 200 controls who were confirmed to have no uterine leiomyomas by clinical examination. Results: Among the four types classified by BMI (over/under 24.0) and percent body fat (over/under 30%), the occult obesity type (BMI<24.0 and percent body fat*30%) had the highest risk. There were no patients of muscular type (BMI*24.0 and percent body fat <30%). Women with more than 0.80 of waist-to-hip ratio were also at significantly higher risk. Conclusions: Occult obesity and upper body fat distribution may lead to the development of uterine leiomyomas. J Epidemiol, 1998 ; 8 : 176-180.
A survey on knowledge and practices of 228 Bangladeshi commercial sex workers (CSWs) concerning AIDS was conducted in the largest brothel in Narayangonj, 20 km from the capital Dhaka in September through December, 1993. Only 18% of the respondents heard about AIDS and 8% knew about its propensity to sexual transmission. AIDS was believed to be curable by 5% of the total respondents. None were regular condom users, but 8% said condom use could prevent HIV infection. Vigorous AIDS awareness campaigns for the CSWs and their clients, leading to regular condom use, is necessary to prevent an explosive epidemic in Bangladesh. J Epidemiol, 1998 ; 8 : 181-183.