Evidence-Based Medicine (EBM) is heralded as a new paradigm of medicine. Is it? What is its link to epidemiology? Does an evidence-based (EB) approach apply also to other health sciences and to public health in particular? What has epidemiology already achieved in these domains, and what remains to be done? What should our priorities be in the coming years? The EB approach is essential in all health sciences at two levels: for problem solving, and for decision making. It applies to all health sciences, be it medicine, nursing, public health, or others. Many epidemiological principles, methods and techniques are put into good use in EBM. The EB "movement" is attractive in it's use of clearly defined procedures, generalizing (not always explicitly) the application of good epidemiologic principles, methods, and techniques. Epidemiology must now contribute to the evaluation of the practice of an EB approach. If one does not have access to a good medical library nor information technology does the EBM paradigm still hold? Hence, clinical and public health guidelines will benefit first from the EBM approach, then daily practice of EBM will follow, conditions permitting. In public health, the challenges of the EB practice are not equally spread across health protection, different levels of disease prevention, and health promotion. The latter represents the most challenging task for epidemiology at any step of EB approach. Epidemiology, if successful in this domain, may help to build an EB health promotion. An Evidence-Based Public Health paradigm may be considered. J Epidemiol, 1997; 7 : 187-197.
This paper describes the dietary patterns of people of Japanese ancestry living in Sao Paulo, Brazil. Two cross-sectional surveys using a food frequency questionnaire (in 1989 and 1995) and self-administered three-day food record (only in 1995) were carried out in randomly chosen firstgeneration (Japan-born) and second-generation (Brazil-born) Japanese living in the city of Sa'o Paulo (n=166), aged 40-69 years at the time of the first survey (1989). Daily intake of rice, bread, milk, fruits and coffee, and infrequent consumption of pork, green tea, black tea, tsukemono (pickled vegetables), seaweed and mushrooms were reported. The mean (±standard deviation) daily proportions of energy from fat among Japan-born participants were 27.2±6.7% for men and 26.2±6.7% for women. The respective figures for Brazil-born Japanese were 30.1 ±7.4% and 29.5±6.4%. These values were quite close to recent estimates for the general Brazilian population in metropolitan areas (about 30%), but seem to be higher than available data from Japan (25.3%). Dietary changes in this migrant population are discussed with focus on nutrients currently implicated in the etiology of major chronic diseases. J Epidemiol, 1997; 7 : 198-204.
Validity of self-reported passive smoking among nonsmokers was evaluated by comparing it with data from smokers in the same household. Eight hundred and ninety-four males and 990 females responded to a lifestyle survey for a cohort study. Subjects consisted of all members aged 20 years or older in each household. One hundred and thirty-six males and 692 females nonsmokers within this group were examined for self-reported passive smoking. It should be noted that guests' smoking was also considered because the question about passive smoking included that when guests visited although guests' smoking could not be evaluated. Four percent of nonsmokers who reported passive smoking almost every day lived in households without smokers. This value was considered a misclassification of negative passive smoking as positive unless these subjects were visited by smoking guests almost every day. Eight percent of nonsmokers who reported no passive smoking had a spouse who smoked and 18% of these subjects also had other smokers in the same household. The misclassification rate for positive passive smoking as negative was thought to be 8% or higher although it was possible that the smoking spouse smoked only outside the home and that household members may live in different structures at the same site. The validity was thought to be fair in comparison with similar previous studies in Western countries. J Epidemiol, 1997; 7 : 205-209.
To investigate the relationship between mental depression and death among elderly persons, a prospective study was conducted. 2, 166 inhabitants aged from 60 to 74 years in the Hidaka district of Hokkaido Prefecture, Japan were employed. From December 1990 to January 1991 we estimated the degree of depression of the subjects, using the self-rating depression scale (SDS) developed by Zung. The subjects were classified into 3 groups according to the average SDS score ( Group A, <2.00; Group B, 2.00-2.39 and Group C>-, 2.40), and were followed up periodically until February 1995 to confirm whether they were still alive. The highest mortality was noted in Group C which consisted of those who had severe depression. Their mortalities for cancer, pneumonia and suicide were significantly high. After the adjustment of age, number of current diseases, smoking state and sex, a similar tendency was noted. Mental depression increased mortality of the aged. Part of this mechanism might be explained by the suppression of immunological resistance. J Epidemiol, 1997; 7 : 210-213.
To estimate the future numbers of patients with mental disorders, schizophrenic disorders, and neurotic disorders, prevalence obtained from the National Patient Surveys conducted by the Ministry of Health and Welfare of the Japanese government was projected by using linear models by age and sex. The prevalence of whole mental disorders and neurotic disorders will increase, while that of schizophrenic disorders will not do so much. The numbers of patients with mental disorders were estimated to be 973 thousand for males and 1, 359 thousands for females in the year of 2008, which were 622 thousand and 733 thousand in 1993, respectively. The disease- specific numbers in 2008 were 562 thousand for schizophrenic disorders and 867 thousand for neurotic disorders, both were 451 and 437 thousand in 1993, respectively. Because of the increase of old age population, the number of old patients with each disorder will also become large. J Epidemiol, 1997; 7 : 214-220.
To estimate prevalence and incidence of adult Still's disease in Japan, and to describe the epidemiological features of the patients, a nationwide epidemiological survey was conducted in 1994. The study consisted of two questionnaires which were distributed to the heads of the relevant departments, randomly sampled, in hospitals throughout Japan. Following major epidemiological findings emerged from the study: (a) The total annual number of patients treated for adult Still's disease was estimated as 1, 100 in 1993 in Japan. The estimated crude prevalence among those aged 16 years or older were calculated as 0.73 and 1.47 per 100, 000 population for males and females, respectively, with the corresponding crude incidence rate of 0.22 and 0.34. (b) The sex ratio (female to male) of the reported patients was 2.1. This female predominance might be specific to Japan, though additional surveys in other countries will be warranted. The mean age of the patients was 38.1 years, and female patients tended to be older than male ones; 50% of the female patients aged 40 years or older, while so did only 28% of the male patients. J Epidemiol, 1997; 7 : 221-225.
We examined serum cholesterol and fatty-acid levels of cord blood and maternal blood samples collected from 193 Japanese fetuses and their mothers. Our study, which is the largest study of this kind ever conducted in Japan, is the first Japanese study reporting that total, high density lipoprotein (HDL) and non-HDL cholesterol levels in females were statistically significantly higher than those in males; the sex differences of total, HDL and non-HDL cholesterol levels were 8.5 mg/dl (P= 0.002), 4.5 mg/dl (P= 0.004) and 4.1 mg/dl (P= 0.045), respectively. The sex difference of total cholesterol was attributable to both HDL and non-HDL cholesterol. The sex of fetuses didn't show evident differences in cholesterol levels in maternal sera. Fatty-acid levels in cord blood were also higher in female fetuses than in male fetuses. However, none of the differences except for monoene fatty acids were statistically significant. Further investigations seem warranted to elucidate the mechanisms involved in our results. J Epidemiol, 1997; 7 : 226-231.
The mean birthweight has decreased recently in Japan. The author assessed the etiology of this trend by comparing the birthweight during the years 1983-1984 and 1993-1994 in Central Japan. All birth certificates of 3767 and 3423 infants were available for 1983-1984 and 1993-1994, respectively. The mean birthweight decreased from 3165 g to 3128 g. The proportion of first infants whose mean birthweight decreased more than that of the other infants increased from 41.0% to 47.1 %. Comparison and multivariate analysis revealed the main cause of decreased birthweight as a decrease of the mean birthweight of first infants and changes of the proportion of birth order. Influences of the increases in the proportion of multiple births and that of low birthweight infants to the decrease of mean birthweight were small. The mean birthweight of infants who were born in public hospitals was lower than that of infants born in clinics, private hospitals, and others. The proportion of low birthweight infants was also highest among the infants born in public hospitals. These results indicate that pregnant women with high risk factors are more likely to be referred to the care of public hospitals. J Epidemiol, 1997; 7 : 232-237.
Risk factors of coronary heart disease (CHD) in Dominicans were compared with those of Japanese and Americans for the presumption of prevalence of CHD in about 2000 persons. Dominican adults aged 20 through 76 years were medically examined in 1993. Data of nationally representative Japanese and Americans which included serum lipid levels were compared. Total cholesterol levels(TCH) in Dominicans were lower than those in Americans. High-density lipoprotein cholesterol levels in Dominicans were lower than those in Japanese and Americans. The prevalence of hypertension and current smoking rates in Dominicans were similar to that of Americans and lower than that of Japanese. TCH in Americans have substantially been declining and those in Japanese were inadequate for preventing CHD. The prevalence of CHD in Dominicans may be lower than that of Americans viewed from the recent levels of main risk factors. Community wide health programs have spread to people with hypertension a decrease in the incidence of CHD should occur. J Epidemiol, 1997; 7 : 238-243.
Since aryl hydrocarbon hydroxylase (AHH) is considered to be responsible for the activation of benzo(a)pyrene (BP) and other polyaromatic hydrocarbons in cigarette smoke to carcinogens, it is important to examine AHH activity in the determination of susceptibility to lung cancer. Lymphocytes from healthy male adults (239) of non-smokers and smokers were cultured in vitro and assayed for non-induced and 3-methylcholanthrene (MC)-induced AHH activity and AHH inducibility (MC-induced AHH activity/non-induced AHH activity). A day-to-day variation in AHH activity was not observed while a seasonal variation was apparent. Very wide differences in noninduced AHH and MC-induced AHH activities were observed. The association of some selected environmental factors and AHH activity was studied. Age was related to non-induced AHH activity (Spearman's rank correlation coefficients (r), r=0.185, p<0.005) and AHH inducibility (r=0.329, p<0.001). Coffee consumption was associated with non-induced (age-adjusted r=0.138, p<0.05) and MC-induced AHH activity (age-adjusted r=0.173, p<0.01). Cigarette smoking was correlated with non-induced AHH activity (age-adjusted r=0.191, p<0.005) and AHH inducibility (age-adjusted r=-0.191, p<0.005). No significant association was observed for any other selected factors, including alcohol intake or broiled food consumption. In conclusion, AHH activity might be affected by cigarette smoking and coffee consumption, and was dependent on the age of the donor. Day-to-day and seasonal variation analyses showed that this assay method was reproducible and reliable and AHH inducibility might be a useful biomarker in cancer epidemiology. As those factors may affect the AHH activity, a careful control of those factors to AHH activity is necessary in epidemiological studies on the association between AHH inducibility in human lymphocytes and lung cancer. J Epidemiol, 1997; 7 : 244-250.
Epidemiological reports reveal that H. pylon is distributed among all population in the world. The present cross-sectional study was undertaken to see the H. pylon seroprevalence rates among the asymptomatic adults, as yet reportedly no such data available in Bangladesh. Serum samples were collected from 181 consecutive subjects who attended at the health check-up centre of Bangladesh Institute of Diabetis, Endocrine and Metabolic Disorders (BIRDEM), Dhaka, during the period of August to November 1995 for medical check up. The mean age of these subjects was 30.33 years (range 20 44 yrs) . Incidentally all were male and belonged to average socioeconomic class. H. pylori specific IgG antibody level was assayed by an enzyme immunoassay kit ElAgen (Clone system). Among the 181 subjects, 166 (92%) had H. pylori specific antibodies and 15 (8%) were seronegative. No significant difference (p<0.90) in seroprevalence rates was observed among different age groups. However, the results of higher seroprevalance rates of H. pylori infection in these asymptomatic adult population of Bangladesh are consistent with that of Africa and India. J Epidemiol, 1997; 7 : 251-254.