The associations between occupational irradiation, cigarette smoking, alcohol drinking and clinical examination data were investigated in Japanese male radiology technicians. The number of investigated examination items was 35, including 29 biochemical serum test, four hematological tests and systolic and diastolic blood pressure. The associations with each factor were evaluated using the multiple linear regression model. As single factors, radiation associated with urea nitrogen, alkaline phosphatase, monoamine oxidase and leukocyte count (four items), smoking associated with albumin-globulin index, zinc sulfate turbidity test, urea nitrogen, creatinine, neutral fat, amylase, serum iron, leukocyte count, hemoglobin and hematocrit (10 items), and drinking associated with creatinine, uric acid, glutamate oxaloacetate transaminase, leucine aminopeptidase, alkaline phosphatase and erythrocyte count (six items). As synergistic factors, the combination of radiation and smoking associated with nine items, radiation and drinking 10 items, smoking and drinking four items, and radiation, smoking and drinking two items. These results suggested that the number of items which radiation associated as single-factor were less than that of smoking and of drinking, however suggested that associations between radiation and examination data was synergistic when combined with smoking or drinking. J Epidemiol, 1995; 5 : 51-57.
To estimate the effect of cigarette smoking on decline of forced expiratory volume in one second (FEW) and forced vital capacity (FVC) with aging in the Japanese population, 461 male workers were longitudinally followed for over seven years. Analyses were conducted on 336 of them who were 30 years old or more, had not changed their smoking habits, were effectively followed up for at least three years, and had acceptable spirometric results in three or more surveys. The annual decline in the indices for each subject was estimated in the form of the slope of a simple regression after correction for height. Significant acceleration of the decline in FEV1 was observed as a result of cigarette smoking, and the magnitude of the effect appeared to be well within the range reported previously for white populations in Europe and North America. The magnitude of the decline in FEW of non-smokers, however, appeared smaller than in previous reports. These findings suggest that the susceptibility of Japanese people to cigarette smoke is similar to that of white populations in terms of acceleration of FEV1 decline, although there may be a racial difference in the magnitude of the decline in the ordinal aging process in Japanese and white populations. J Epidemiol, 1995; 5 : 59-65.
Annual gastric cancer screening has been recommended for residents over the age of 40 in Japan. We conducted a cost-effectiveness study in order to determine an optimal screening interval in both genders using a cohort model. Hypothetical cohorts of 100, 000 asymptomatic individuals aged 40 were assumed to have taken part in each strategy with a follow-up period of 20 years. In order to evaluate both the cost and effectiveness of the gastric cancer screening, a Markov modeling process was used. The incremental cost per year-of-life saved in gastric cancer screening, compared to no screening, illustrates a tendency toward a higher cost per year-of-life saved in both, shorter than and longer than 3-year screening intervals. Our results indicate that the recommended method of annual screening represents the least cost-effective option regarding both genders. The incremental cost per year-of-life saved of annual screening strategy was 2, 764, 000 yen (25, 127) for males and 3, 753, 000yen (34, 118) for females, compared to no screening. The figures of the incremental cost per year-of-life saved in the three year screening interval at 1, 670, 000 yen (15, 182) for males and 2, 431, 000yen (22, 100) for females clearly show this strategy as the most efficient solution in both genders, compared to no screening. However, the screening program on annual basis is not considered to be less efficient than other screening programs so far. The cost-effectiveness of gastric cancer is decreasing as its incidence decreases. It is very important for policy makers to pay attention to the incidence of diseases targeted by screening programs and to evaluate screening interval. J Epidemiol, 1995; 5 : 67-74.
We conducted an epidemiological study on prevalence of antibodies to hepatitis C virus (anti-HCV) among Japanese workers with a history of blood transfusion and on risks of blood transfusion for anti-HCV positivity. Of 3, 693 workers, 241 (76 males and 165 females) had a history of blood transfusion. For each of these 241 cases, a control, matched for area of residence, sex and age, was selected from those workers who never had blood transfusion. Data on these 482 workers were analyzed. Prevalence of anti-HCV was 12.4% among subjects with a history of blood transfusion and 3.7% among those without (p<0.001). Among subjects with a history of blood transfusion, prevalence of anti-HCV rose with age and was higher in males (19.7%) than in females (9.1%) (p< 0.05). Before 1970, most transfused blood was supplied by commercial donors, and prevalence of anti-HCV was much higher among subjects who received blood transfusion before 1970 than among those who received blood transfusion after 1970. A logistic regression analysis was conducted. Adjusted relative risks for anti-HCV positivity were 3.70 (95% confidence interval : 1.71-8.00) for blood transfusion (p<0.001), 1.98 (1.01-3.87) for age (age, *50 vs age 20-49) (p<0.05), and 1.51 (0.75-3.01) for sex. J Epidemiol, 1995; 5 : 75-80.
To evaluate the feasibility of mail questionnaire for eidemiological studies in general population in Japan, we mailed six types of questionnaires which differed in lengths and topics to male residents drawn from a telephone directory of Gifu City in Japan. Those who were allotted to the shortest questionnaire and not responded after the initial mailing were assessed by followup processes with a second mail and a personal contact by telephone. We classified the subjects as early (on the first mailing) and late (on the second mailing) respondents, and nonrespondents (respondents to telephone interview), and compared histories of cigarette smoking and drinking, and environmental exposure to solvents among these three groups. The response rates after the first mailing ranged from 32-54% across the six types of questionnaires. Although somewhat lower response rates were noted for the longer questionnaires, there were no significant differences in the response rates by type of questionnaire. Although the second mailing increased the response rate to nearly 70%, there was a evidence of non-response bias. Cigarette smokers and drinkers were more likely to be the nonrespondents. J Epidemiol, 1995; 5 : 81-85.
The present study aimed at examining relationships between baseline lipids to 10-year mortality from all causes and cancer. Subjects comprised 1202 men and 2054 women ranging in age from 40 to 80 years living in Toda City, an urban area of Japan. They were residents who had completed multiphasic health check-ups as the baseline survey between March 1979 and February 1981. Relationships of fasting lipids at baseline to 10-year deaths were analyzed using univariate and multivariate logistic regression analysis. One hundred and seventy-two died over the 10 years. Cancer was the most common cause of death, accounting for 44 percent of deaths, followed by stroke, and congestive heart failure. Total serum cholesterol (TC) at baseline was inversely related to all-cause mortality in men, even after adjustment of body mass index, systolic blood pressure, smoking habits, and drinking habits, with odds ratio showing 0.55 in 2nd tertile and 0.74 in 3rd tertile vs 1.00 in first tertile. In women, an inverse relationship of TC to 10-year all-cause mortality did not reach significant level either in crude or adjusted odds ratios. A significant inverse relationship between baseline high density lipoprotein cholesterol (HDL-C) and all-cause mortality in adjusted odds ratios was found in men alone. Serum triglyceride (TG) and (TC-HDL-C)/TC(atherosclerotic index, Al) showed no consistent relationship to mortalities from all causes in either men or women. A relationship of TC to cancer death was insignificant in both crudeand adjusted odds ratios in men. A significantly inverse relation of HDL-C to cancer death was recognized in adjusted odds ratios in men. The relation did not substantially differ according to observation period. An inverse relation of HDL-C with cancer death in women was not significant. Relationships of TG and Al to cancer death were diverse for both sexes. The present study thus revealed the inverse relationship of TC and HDL-C to all-cause and cancer mortalities in men. J Epidemiol, 1995; 5 : 87-94.
A matched case control study on MRSA urinary tract infection was carried out. The purpose of our study was to evaluate the effect of the use of antibiotics, the use of the third generation cephems, the hypoalbuminemia and the indwelling of catheter on the occurrence of MRSA urinary tract infection among the elderly. From April 1991 to March 1994, there were 8 inpatients who were suffered from MRSA urinary tract infection, which were used as cases. The twenty four age-and ADL-matched inpatients with non-MRSA urinary tract infection, three controls per case, were used as controls. Compared to the non-MRSA patients, the MRSA patients had a larger amount of antibiotics prior to the bacterial culture (1.3±0.9 vs 0.3±0.6, mean±SD, p<0.05). The third generation cephems were more commonly used in the MRSA patients than in the non-MRSA patients (50.0% vs 4.2%, p<0.05). The level of serum albumin was significantly lower in the MRSA patients than in the non-MRSA patients (3.4±0.6 vs 4.0±0.4 g/dl, p<0.05). Even after controlling confounding factor such as hypoalbuminemia, the use of the third generation cephems was a risk for MRSA urinary tract infection among the elderly (OR: 3.37, 95% Cl : 1.11-10.28). In the elderly, use of the third generation cephems seems to be an important risk factor for MRSA urinary tract infection. J Epidemiol, 1995; 5 : 95-98.
A hospital-based case-control study was conducted to examine changes in odds ratio of risk factors of breast cancer according to age group. Patients aged 30 to 69 years were selected as subjects. Cases were 1, 110 female patients with breast cancer diagnosed during 1988 to 1992 at Aichi Cancer Center Hospital. Controls were 20, 044 first-visit non-cancer patients during the same period. Logistic model was applied separately to the four age groups (30-39 years, 40-49 years, 50-59 years and 60-69 years at first visit), to estimate odds ratios of reproductive history, family history of breast cancer, body mass index, smoking, and drinking habits. Late menarche tended to give an odds ratio below unity in the age groups older than 50 years. Child birth and age at first delivery were significant risk factors for all four age groups. Odds ratio of having a sister with breast cancer was consistently high among the four age groups, while that of having mother with breast cancer was not. Body mass index over 24 was found to significantly increase the risk in age group 60-69. In age group 40-49, the smoking and drinking habits significantly increased the risk. These findings suggested the attribution of the risk factors to breast cancer could not always be similar among the age groups. J Epidemiol, 1995; 5 : 99-105.