We conducted a study to evaluate tuberculosis (TB) risk in Japan by work performed, either paid or unpaid. We collated information on sex, age, employment category, occupation, and family history from 1120 registration cards of new TB cases at two wards in Nagoya City over seven years (1989-1995). We used census data and data from the Survey of Physicians, Dentists and Pharmacists conducted in 1990 to estimate the population at risk by employment category and occupation. Elevated TB incidence rates were observed for female nurses (SIR: 3.81; 95%Cl: 1.97-6.65), clinical laboratory technicians (SIR: 25.00; 6.81-63.99), and males without a paid job (SIR: 1.35; 1.20-1.53). A work environment conducive to transmission may have increased the TB risk in female nurses and clinical laboratory technicians. Male jobless people and institutionalized elderly residents may have enhanced the TB risk for males without a paid job. J Epidemiol, 2000 ; 10 : 1-6

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Cigarette modification trends and the relationship between nicotine yields and consumption in Japan were examined over the 27 years between 1969-1996. Data on cigarette use were obtained from reports published by the government and tobacco manufacturers. Over the study period, there has been a coherent pattern of cigarette modification in Japan. The sales-weighted average yields have declined from 20.7 mg tar and 1.64 mg nicotine/cigarette in 1969 to 8.7 mg tar and 0.72 mg nicotine/cigarette in 1996. On the other hand, the average daily consumption per smoker has continuously increased over the same period. Average nicotine yields and daily cigarette consumption have significant negative correlations among both males and females. This relationship was observed even after controlling for the price changes of cigarettes over time. It is indicated that smokers have compensated for reduced nicotine yields by increasing daily consumption. This may have offset potential benefits of the continuous decline in tar and nicotine yields to smokers' health. J Epidemiol, 2000 ; 10 : 7-15

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We conducted a questionnaire survey of public kindergarten, elementary and high school teachers in Mie Prefecture, concerning smoking habits and attitudes from November 1995 to February 1996. A self-reporting questionnaire was sent to approximately 16, 000 teachers and school employees. The questionnaires were collected in a way which took into consideration the privacy of the respondents. A total of 13, 998 questionnaires were returned. The percentages of smokers among the teachers were 44.7% for males and 3.1 % for females, percentages which are lower than those for the general Japanese population. Almost all of the men and women agreed that anti-smoking education is needed. Most of those who did not feel anti-smoking education was needed were smokers themselves. Seventy percent of both men and women responded that anti-smoking education was a teachers'duty, however, only thirty-six percent of the male and twenty-one percent of the female teachers had actual experience at such education. Finally, almost all teachers wish that schools were totally smoke-free or had a partial ban on smoking and believe that school anti-smoking policies in Japan should be introduced. J Epidemiol, 2000 ; 10 : 16-21

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This longitudinal study examines the effect on mortality of regular use of the basic health examination under the Health Services for the Elderly Act and heterogeneity of the effect according to levels of physical and mental health status among community dwelling elderly persons. Of persons aged 65 and older who lived in Otsuki town, Kochi prefecture, and completed a questionnaire survey about health in February 1991, 1, 470 survivors on the anniversary of the baseline survey were followed by the end of March 1996. Regularity of getting the examination was determined by the history of use of the examination in 1990 and 1991. Mortality reduction associated with annual use of the examination was observed in both the 6574 and the 75 and older age groups and the benefit got smaller with advancing in age. In the 75 and older age group, the benefit from annual use of the examination was restricted to persons having no impairment in physical activities of daily living and those having favorable mental health. Biennial use of the examination was associated with the same amount of mortality reduction as annual use among persons having chronic conditions under treatment in the 65-74 age group. Regular use of the basic health examination at old ages is effective and the effectiveness varies by age range and level of functional health status. J Epidemiol, 2000 ; 10 : 22-28

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A nationwide epidemiologic survey of idiopathic hypoparathyroidism and pseudohypoparathyroidism was conducted in 1998 to clarity the prevalence of the two disorders in Japan. From a total of 14, 100 departments of pediatrics, internal medicine, neurology, and endocrinology in whole Japan, 2952 (20.9%) study departments were selected at random. Of these departments receiving the first questionnaire, 1855 (62.8%) responded. From these departments 390 patients with idiopathic hypoparathyroidism and 203 with pseudohypoparathyroidism who visited the hospitals in 1997 were reported. The total numbers of patients were estimated to be 900 (690-1100) for idiopathic hypoparathyroidism and 430 (330-520) for pseudohypoparathyroidism (95% confidence intervals in parentheses). Using these data, the period prevalence of the diseases were 7.2 (5.5-8.8) per million population in idiopathic hypoparathyroidism, and 3.4 (2.6-4.2) in pseudohypoparathyroidism (95% confidence intervals in parentheses). J Epidemiol, 2000 ; 10 : 29-33

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A cross-sectional observation was performed to assess the relationship between the coagulation-fibrinolysis system and the subclinical indicators of arteriosclerosis in a healthy male population. Subjects were 445 workers (18.9-49.4, Av.36.2yrs) in viscose rayon manufacturing factories in Japan. Coagulation-fibrinolysis parameters determined were D-dimer(DD), thrombin antithrombinIII complex (TAT), tissue plasminogen activator (TPA), and plasminogen activator inhibitor 1 (PAI1). The following indicators of arteriosclerosis were examined; systolic and diastolic blood pressure (SBP, DBP), stiffness parameter of the carotid artery using ultrasound (3), pulse wave velocity of the aorta (PWV), and a number of lacunar infarctions from brain MRI. After age-stratification(-29, 30-39, 40+yrs), the subjects were classified into quartiles by coagulation-fibrinolysis parameters. The mean values of SBP and DBP and β and PWV the prevalence of brain infarctions were compared across these quartiles by means of analysis of variance, chi-square test, respectively. Multivariate analysis was also employed to adjust other risk factors. In conclusion, SBP and β DBP and, , PWV were elevated by increase of PAl1, TAT, respectively, in the 40+ years group even after adjustment for other possible risk factors. DD had no relation to any of the indicators of arteriosclerosis. None of the coagulation-fibrinolysis parameters had any relation to brain infarctions. J Epidemiol, 2000 ; 10 : 34-41

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The effect of exposure to Japanese cedar pollen (JCP) in early life on subsequent sensitization to it was evaluated. Specific IgE antibody to JCP was examined in 440-504 school children in a rural town each year during 1995-98. The amount of dispersed pollen measured by a Durham sampler widely ranged from 165 to 5941 grains/cm2/year during this period. The amount had been measured during the period of 1982-91 in which these children were born, and it also widely ranged from 148 to 8566 grains/cm2/year. Children born during November to January, who were exposed to JCP within 6 months of age, increased at the risk of sensitization to JCP, especially severe sensitization, relative to those born in the other months. Age-adjusted prevalence rate ratio (RR) of having a JCP-IgE*15 U/ml (control; <0.35 U/ml) for children born in December to February relative to children born in the other months was 1.74 (95% confidence interval; 1.06-2.87, examined in 1998), and for those born in November to January was 1.57 (95% CI; 1.00-2.46, examined in 1997). The risk of sensitization to JCP was low for those born in May to July (RR=0.42, 95%Cl; 0.19-0.93, examined in 1998). There was also a strong correlation between the amount of the dispersed pollen during the period of 2-6 months after birth and the prevalence of sensitization to JCP. J Epidemiol, 2000; 10: 42-47

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Even though it is important in improving the quality of life to evaluate the long-term prognosis of patients with ulcerative colitis in comparison with the general population, it is unknown in detail. One hundred and seventeen cases followed-up for 10 years or more were evaluated to define the long-term prognosis of ulcerative colitis by the person-years method. The estimated number of death (E) was 14.5, and the observed number of death (0) was 20. The O/E ratio was 1.38 and confidence interval was 0.84-2.13, showing no significant difference between E and O. Evaluation of change in th O/E ratio at 5-year intervals revealed a decrease in both the males and females, with a significant difference observed between the ratios in 1960 and 1965 (each p<0.05). Generally, the death rate was significantly higher in the patients with ulcerative clitis than in the general population between 1953 and 1965 but did not significantly differ thereafter. On the other hand, the E from malignant tumors was 3.94, and the 0 was 4; the O/E ratio was 1.02 and 95% confidence interval was 0.27-2.60, showing no significant difference between E and O. J Epidemiol, 2000 ; 10 : 48-54

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Physical exercise is expected to improve and maintain physical function in older people, thus promoting health and preventing or postponing the onset of disability in later life. The Sendai Silver Center Trial (SSCT) was a randomized controlled trial designed to evaluate the efficacy of exercise training among healthy free-living older people. Sixty-five eligible participants, aged from 60 to 81 years, were randomly allocated to an exercise group or a control group. The subjects in the exercise group were asked to attend training classes at the Sendai Silver Center, a municipal health and welfare facility in the center of Sendai City, at least twice a week for 25 weeks. Each training class, lasting two hours, started with a warm-up session, followed by an endurance session with a bicycle ergometer, and a resistance exercise training session using rubber films, and ended with a cool-down session. The subjects in the control group were asked to attend recreational classes at the Center twice a month. There were no drop-outs or accidents during the intervention. Comparison of maximum oxygen consumption (VO2max) before and after the 25-week intervention revealed a significant increase in the exercise group (2.1 ml/kg/min) but no significant change in the control group. Our result is equivalent to the participants becoming younger in aerobic capacity by five years after six months of exercise training. J Epidemiol, 2000 ; 10 : 55-64

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This study attempts to clarify the distribution patterns of delay between HIV transmission and the first hospital visit among HIV-infected persons and AIDS cases in Japan except those infected through blood products. Such hospital visit patterns were analyzed, and the rates of reporting for HIV/AIDS surveillance among diagnosed HIV-infected persons and AIDS cases in hospitals were shown. From 1991 to 1997, a survey and subsequent follow-up were conducted among HIV-infected persons and AIDS cases diagnosed at 74 hospitals in Tokyo. The numbers of HIV-infected persons and AIDS cases were 590 and 208, respectively. The percentage of patients whose estimated date of HIV transmission was obtained ranged 23-41 % among Japanese and non-Japanese HIV-infected persons and AIDS cases. Among these patients, 28% to 86% showed a 3-year delay between HIV transmission and their first hospital visit. The rate of HIV-infected persons who continued to visit hospitals within 1 year after their first visit was 77% for Japanese and 45% for non-Japanese; among those after 1 year or more following their first hospital visit the rate was more than 80% among Japanese and over 70% among non-Japanese. The rate of reporting to HIV/AIDS surveillance among diagnosed HIV-infected persons and AIDS cases was 90% or more after 1994 in Japan. The delay between HIV transmission and the first hospital visit was suggested to be very long. Not a few patients stopped visiting hospitals after only a short time. Most diagnosed HIV-infected persons and AIDS cases were reported to the surveillance system of Japan. J Epidemiol, 2000 ; 10 : 65-70

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