Japanese Migrants Research Articles

Weight excess and abdominal fat in the metabolic syndrome among Japanese-Brazilians

Obesity, especially abdominal, has been associated with cardiovascular risk factors such as dyslipidemia, hypertension and diabetes mellitus (DM). The importance of these risk factors among Japanese-Brazilians was previously shown, although obesity is not a typical characteristic of Japanese migrants. In this study the prevalence of weight excess and central adiposity (CA) among Japanese-Brazilians and their association with metabolic disorders was evaluated. A sample of 530 1st and 2nd generation Japanese-Brazilians (aged 40 - 79 years) went through anthropometric and blood pressure measurements, lipid profile and oral glucose tolerance tests. The prevalence rate (point and confidence interval) of overweight was calculated using a cut-off value of >26.4 kg/m2. CA diagnosis was based on waist-to-hip circumference ratio (WHR): greater-than-or-equal 0.85 and 0.95 in women and men, respectively. The prevalence of weight excess was 22.4% (CI 95% 20.6 - 28.1), and CA was 67.0% (95% CI 63.1 - 70.9). In addition to higher prevalence of DM, hypertension and dyslipidemia, stratifying by BMI and WHR, people with weight excess and CA revealed a poorer metabolic profile: blood pressure levels were significantly higher among those with weight excess with or without CA; CA individuals had higher glucose, triglycerides, total and LDL cholesterol, and lower HDL than those without weight excess or CA; fasting insulinemia was significantly higher among subjects with weight excess (with or without CA) than among those without weight excess or CA. Comparing subgroups with and without CA supports the hypothesis that abdominal fat accumulation represents a risk factor for insulin resistance-related diseases, even among Japanese descendants. The increased prevalence of metabolic syndrome among Japanese migrants could be attributed to visceral fat deposition, which has been implicated in the genesis of insulin resistance.

From Ethnic Affinity to Alienation in the Global Ecumene: The Encounter between the Japanese and Japanese-Brazilian Return Migrants

From Ethnic Affinity to Alienation in the Global Ecumene:The Encounter between the Japanese and Japanese-Brazilian Return Migrants1 Takeyuki (Gaku) Tsuda (bio) Takeyuki (Gaku) Tsuda University of California, San Diego Takeyuki (Gaku) Tsuda Takeyuki Tsuda received his doctorate in anthropology from the University of California at Berkeley and is currently Associate Director of the Center for Comparative Immigration Studies at the University of California—San Diego. He is the author of eight published articles, including "When Identities Become Modern: Japanese Immigrants in Brazil and the Global Contextualization of Identity" (Ethnic and Racal Studies, 2001); "Acting Brazilian in Japan" (Ethnology, 2000); "Transnational Migration and the Nationalization of Ethnic Identity among Japanese-Brazilian Return Migrants" (Ethos, 1999); and "The Permanence of 'Temporary' Migration: The 'Structural Embeddedness' of Japanese-Brazilian Migrant Workers in Japan" (Journal of Asian Studies, 1999). Notes 1. This article is based on over twenty months of intensive fieldwork and participant observation in both Japan and Brazil. Nine months were spent in Brazil (1993-1994) among two separate Japanese-Brazilian communities in the cities of Porto Alegre (Rio Grande do Sul) and Ribeirão Preto (São Paulo). During my subsequent one-year stay in Japan (1994-1995), I conducted fieldwork in the cities of Kawasaki (Kanagawa prefecture) and Oizumi/Ota (Gunma prefecture), where I worked in a large electrical appliance factory with Japanese-Brazilian and Japanese workers as a participant observer for four intensive months. Close to 100 in-depth interviews were conducted with Japanese-Brazilians and Japanese workers, residents, employers, and officials. See Tsuda, "Ethnicity") for a self-reflexive analysis of the methodological implications of my fieldwork experiences in Japan as an ethnically ambiguous anthropologist. 2. Excluding the approximately 650,000 Korean-Japanese who are still registered in Japan as "foreigners." Although most of them were born and raised in Japan, they are not granted Japanese citizenship and have not naturalized. The population of Chinese in Japan remains higher than that of the Brazilian nikkeijin. In 1994, there were 214,389 Chinese registered as foreigners in Japan. In addition, there were 39,552 illegal visa overstayers. 3. See Tsuda, "Motivation," for an analysis of the causes of Japanese-Brazilian return migration. 4. Of course, the Japanese-Brazilians have not always been regarded so highly. Before and during World War II, when Japan was a global imperialist menace, they were subject to considerable prejudice and ethnic repression in Brazilian society. See Tsuda, "When Identities," for a historical analysis of the Japanese in Brazil. 5. In 1989, a mere 14,528 Brazilians were registered as foreigners in Japan. Three years later, the population had exploded tenfold to 147,803, and their numbers have continued to expand steadily since then, despite Japan's prolonged economic recession. 6. Under the new immigration provisions, the nikkeijin are allowed to enter Japan on two types of visas, both of which can be renewed an indefinite number of times and have no activity restrictions. 7. Unless otherwise indicated, all English translations of interviews and published texts are my own. 8. See Tsuda, Strangers, for further analysis of Japanese-Brazilian ethnic experiences in Japan. 9. In a similar vein, Ong (738-9) observes that notions of cultural difference (instead of racial difference) are employed being increasingly in the ethno-political discourse of Western Europe to marginalize immigrant or minority groups. 10. See Tsuda, Strangers, for an analysis of how the Brazilian nikkeijin assert their Brazilianness in Japan. 11. Non-nikkeijin Brazilian spouses of Japanese-Brazilians are legally admitted to Japan on the same visas. 12. For a more extensive discussion of Japanese ethnic attitudes toward the Japanese-Brazilians, see Tsuda, Strangers. 13. Ethnic and national identity are considered synonymous in the Japanese case, since the nation is seen as composed of one ethnic group (see also De Vos and Suárez-Orozco 251; Ivy 3-4; Yoshino). 14. As George De Vos notes, "It is yet a basic incongruity to consider the possibility that one could be Japanese and maintain adherence to a [culturally different] background" (13). 15. Marginal figures in Japanese history have served as metaphors for symbolic transformations in collective self-representations (Ohnuki-Tierney, Monkey). Renato Rosaldo (207-9, 215-7) claims...

From Ethnic Affinity to Alienation in the Global Ecumene: The Encounter between the Japanese and Japanese-Brazilian Return Migrants

The return migration of the Japanese-Brazilians from Brazil “back” to Japan is the most recent chapter in an interesting migration legacy that started with emigration from Japan at the beginning of the twentieth century and has now ended with immigration to Japan at the end of that century. Japanese emigration to Brazil began in 1908 and continued in significant numbers until the early 1960s. Many of the emigrants were farmers who were suffering from poverty in Japan’s rural areas and were drawn to Brazil by promises of opportunity and wealth in its expanding coffee plantations. Although most of them went to Brazil as dekasegi (temporary migrant workers) with dreams of returning to Japan in several years with considerable wealth, reality proved to be considerably more difficult, and their hopes for eventual repatriation became impossible. As a result, a vast majority of them settled permanently in Brazil with their families.

Colorectal cancer incidence in Asian migrants to the United States and their descendants.

To examine the incidence of colorectal cancer among Asian residents of the United States according to country of birth. We determined the incidence of colorectal cancer during 1973-1986 among Asian residents in three areas of the western United States (Hawaii, San Francisco/Oakland SMSA, and western Washington state) in relation to country of birth. Numerators for the rates were obtained from the Surveillance, Epidemiology and End Results (SEER) program; a special tabulation of the 1980 US Census was used to estimate the size and composition of the population at risk. US-born Japanese men experienced incidence rates of colorectal cancer twice as high as foreign-born Japanese men and about 60% higher than those of US-born white men. Incidence among US-born Japanese women was about 40% higher than that among Japanese women born in Japan or US-born white women. Foreign-born Chinese men had about the same incidence of colorectal cancer as US-born white men, while US-born Chinese men experienced slightly reduced rates. Chinese women had rates that were generally 30-40% lower than that of US-born white women, regardless of place of birth. Incidence rates for both US-born and foreign-born Filipinos were 20-50% those of US-born whites. These findings suggest that one or more exposures or characteristics that differ between Japanese migrants and their descendants affect the development of colorectal cancer.

The economic adaptation of migrants and the cooperative behavior by generalized exchange : The rotating credit association of Japanese migrants in Buenos Aires

The economic adaptation of migrants and the cooperative behavior by generalized exchange : The rotating credit association of Japanese migrants in Buenos Aires

Combined influence of genetic and dietary factors on colorectal cancer incidence in Japanese Americans.

Colorectal cancer (CRC) rates for Japanese migrants to the United States increased rapidly to surpass the level of the host population. CRC rates for the Japanese in Hawaii and California are now the highest in the world. Rates for this disease have also increased in Japan, presumably as the result of the westernization of the diet. A series of population-based studies in Hawaii was undertaken to determine which dietary factors are responsible for this remarkable susceptibility of the Japanese to CRC and whether genetic factors are also involved. A first case-control study suggested that a high intake of red meat is a major risk factor for the disease in Hawaii Japanese men and that family history of CRC among first-degree relatives may strongly modify this association. A case-control family study is currently being completed to explore further the interaction between family history and the intake of red meat after adjustment for environmental covariates among family members. Also, a segregation analysis will guide gene discovery studies among high-risk Japanese families being recruited in the Cooperative Family Registry for Colorectal Cancer Studies. Retrospective and prospective studies are also ongoing to test associations of CRC with specific polymorphisms in genes controlling the metabolic activation or detoxification of the carcinogens associated with a diet high in red meat. Preliminary results suggest an association of the combined rapid NAT2 genotype and rapid CYP1A2 phenotype with CRC in individuals consuming well-done red meat. Populations in which dramatic changes in cancer incidence have occurred may offer opportunities to identify gene-environment interactions.

Transnational Migration and the Nationalization of Ethnic Identity among Japanese Brazilian Return Migrants

By examining the ethnic experiences of Japanese Brazilian return migrants in Japan, this paper explores how the dislocations of migration can produce a form of deterritorialized nationalism in which national loyalties are articulated outside the territorial boundaries of the nation‐state. The Japanese Brazilians respond to their ethnic exclusion in Japan, as well as their negative experiences with Japanese cultural behavior and discrimination, by discarding their previously stronger Japanese identity and affirming their Brazilian cultural distinctiveness through contextually redefining their ethnic behavior. The resulting resurgence of Brazilian national sentiment becomes an ethnic counteridentity that is asserted in opposition to what is perceived negatively as Japanese. This indicates that transnational movements of people which cross national boundaries do not necessarily subvert the hegemonic dominance of the nation‐state over individual consciousness.

Mortality among Japanese migrants living in the State of Parana, Brazil

Taking as a premise that the study concerning the morbimortality of migrant populations may make a contribution to a better understanding of the epidemiology of diseases, mainly the chronic-degenerative ones and their related risk factors, the aim of this study is an analysis of the mortality experience of a population of migrants born in Japan, but living in the State of Paraná, Brazil, and a comparison of their pattern of mortality with those of Japan and Paraná. The population studied was composed of the Japanese migrants - Issei - living in the State of Parana, Brazil, of more than 50 years of age, identified in the X General Brazilian Census of 1st September, 1991. Information on deaths which occurred between 1st March 1990 and 28th February, 1993, was obtained through the Ministry of Health data base. The main causes of death were analysed after the calculation of the age-adjusted death rates, using the world standard population older than 50 years old, for each sex, for the Issei, the inhabitants in Japan and in Paraná. Standardized Risk Ratio - SRR - and respective 95% confidence interval were estimated for selected causes among Issei versus the population living in Japan and Issei versus persons living in Paraná. Among the main results, it was observed that the female Issei mortality rate was in an intermediary position when compared to Japan's and Paraná's rates, while men showed figures quite close to the Japanese rates. Concerning the specific causes, it was observed that among male Issei, when compared to the Japanese population, the rates were significantly lower for stomach, but higher for diabetes and ischaemic heart diseases. Regarding the female Issei aged 50 or more years old, only the death rate for lung cancer was itself significantly lower than that of Japanese women. When compared to the Paraná pattern, the male Issei rates were lower regarding ischaemic heart and cerebrovascular diseases. Concerning stomach and lung cancer, there was no statistical difference. The female Issei rates were lower for lung cancer and ischaemic heart diseases. Regarding diabetes and cerebrovascular diseases, no significant difference among rates was detected. The results obtained make it possible to assert a deviation in the Issei pattern of mortality from that of their country of origin (Japan) and a perseptible approximation to the pattern of their new homeland (Paraná). Such observations suggest the influence of socio-cultural factors, mainly dietary habits, on their morbi-mortality.

The Questionable Role of Saturated and Polyunsaturated Fatty Acids in Cardiovascular Disease

A fat diet, rich in saturated fatty acids (SFA) and low in polyunsaturated fatty acids (PUFA), is said to be an important cause of atherosclerosis and cardiovascular diseases (CVD). The evidence for this hypothesis was sought by reviewing studies of the direct link between dietary fats and atherosclerotic vascular disease in human beings. The review included ecological, dynamic population, cross-sectional, cohort, and case-control studies, as well as controlled, randomized trials of the effect of fat reduction alone. The positive ecological correlations between national intakes of total fat (TF) and SFA and cardiovascular mortality found in earlier studies were absent or negative in the larger, more recent studies. Secular trends of national fat consumption and mortality from coronary heart disease (CHD) in 18–35 countries (four studies) during different time periods diverged from each other as often as they coincided. In cross-sectional studies of CHD and atherosclerosis, one group of studies (Bantu people vs. Caucasians) were supportive; six groups of studies (West Indians vs. Americans, Japanese, and Japanese migrants vs. Americans, Yemenite Jews vs. Yemenite migrants; Seminole and Pima Indians vs. Americans, Seven Countries) gave partly supportive, partly contradictive results; in seven groups of studies (Navajo Indians vs. Americans; pure vegetarians vs. lacto-ovo-vegetarians and non-vegetarians, Masai people vs. Americans, Asiatic Indians vs. non-Indians, north vs. south Indians, Indian migrants vs. British residents, Geographic Study of Atherosclerosis) the findings were contradictory. Among 21 cohort studies of CHD including 28 cohorts, CHD patients had eaten significantly more SFA in three cohorts and significantly less in one cohort than had CHD-free individuals; in 22 cohorts no significant difference was noted. In three cohorts, CHD patients had eaten significantly more PUFA, in 24 cohorts no significant difference was noted. In three of four cohort studies of atherosclerosis, the vascular changes were unassociated with SFA or PUFA; in one study they were inversely related to TF. No significant differences in fat intake were noted in six case-control studies of CVD patients and CVD-free controls; and neither total or CHD mortality were lowered in a meta-analysis of nine controlled, randomized dietary trials with substantial reductions of dietary fats, in six trials combined with addition of PUFA. The harmful effect of dietary SFA and the protective effect of dietary PUFA on atherosclerosis and CVD are questioned.

Increase in mortality associated with the presence of diabetes mellitus in Japanese-Brazilians

As part of a study involving Japanese migrants, living in a developed city in the state of S. Paulo, Southeastern Brazil, a four-year experience of mortality among diabetic and non-diabetic subjects is described and their respective death rates are compared. In 1993, a cohort of 530 Japanese-Brazilians (236 issei or 1st generation and 294 nisei or 2nd generation) of both sexes, aged 40 from to 79 years old, were identified. At that time, 91 (17%) were classified as non-insulin-dependent diabetic subjects (NIDDM), 90 (17%) with impaired glucose tolerance (IGT) and 349 (66%) as normal, according to WHO criteria. In 1996, families were questioned with a view detecting the deaths which had occurred among the subjects previously studied. This information, in addition to that from death certificates was used to record the date and the causes of death. Mortality rates for all causes and for specific causes (circulatory and renal diseases) were obtained for the three groups of subjects, by glucose tolerance status. Proportional hazard regression models were used to compare the mortality rates, adjusted for several covariables (gender, age, generation, hypertension, dyslipidemia, obesity and serum creatinine). Crude mortality rate ratios for all causes and specific causes, for NIDDM, and normal subjects were 2.95 (95% CI: 1.10-7.62) and 4.57 (95% CI: 1.31-16.48), respectively. No difference was observed between the crude mortality rate ratio for IGT and normal subjects. After simultaneous adjustments for the covariates, higher mortality rates for specific causes were observed among NIDDM than in the normal subjects (mortality rates ratio: 3.86; 95% CI: 1.11-13.38). These results in Japanese-Brazilians are consistent with previous reports of increased mortality in other diabetic subjects, thus confirming the adverse effect of this metabolic disturbance on mortality among diabetic subjects.

Modernization as creative problem making: political action, personal conduct and Japanese overseas prostitutes

This paper is concerned with how and why the karayuki-san – Japanese female migrants who worked as sexual labourers from 1880 until the start of the Pacific War – became an issue that had to be dealt by successive Japanese governments. The argument of the paper is that the creation of the karayuki-sanas a problem of government cannot be divorced from the concurrent emergence of changes in the ethics of personal conduct under the rubric of ‘modernization’. The process in which the karayuki-sanbecame an issue worthy of governmental attention and action coalesced around a theme central to the politics of modernization: how to achieve cohesion between the principles of political action and personal conduct.

Cancer prevention

Cancer prevention

Dietary patterns in Japanese migrants to southeastern Brazil and their descendants.

This paper describes the dietary patterns of people of Japanese ancestry living in São 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 first-generation (Japan-born) and second-generation (Brazil-born) Japanese living in the city of São 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.

Human T-cell lymphotropic virus type I infection among Japanese immigrants in Peru

Objective: A prospective study was conducted to determine the prevalence of human T-cell lymphotropic virus type I (HTLV-I) infection among healthy Japanese migrants and their descendents in Peru. Methods: A total of 407 persons were enrolled at the Peruvian-Japanese Medical Center in Lima during routine visits for health evaluations. Each study volunteer was interviewed to obtain clinical and epidemiologic data, and a blood sample was obtained for HTLV-I testing. Sera samples were initially tested for antibody by enzyme-linked immunosorbent assay (ELISA). All ELISA reactive sera were further tested by Western Blot assay, and the results were recorded in accordance with the manufacturer's recommendations. Results: Among the 407 study volunteers, HTLV-I infection was demonstrated in 6.8% ( 19 280 ) of females and 3.2% ( 4 127 ) of males. Infection rates significantly increased with age, with 28.5% of volunteers over 80 years of age being positive (P < 0.05). The migrants from Japan had the highest infection rate (15.8%), whereas none of the second generation volunteers were positive (P < 0.05). The incidence among those with ancestors from Okinawa was 9.3%, and for those with ancestors from the central zone of Japan, 1.2% (P < 0.05). Conclusions: These data indicated that HTLV-I infection rates were highest among the older volunteers from Okinawa and Kyushu, and that evidence of infection was not found among their offspring.

Comparative Analysis of Migration Patterns between the Koreans Living in Japan and the Japanese

There are many studies on Japanese internal migration, however the movements of foreigners living in Japan have not been studied specifically until now, in part due to data unavailability. This study tries to clarify the in- and out-migration patterns of the Japanese and foreign population living in the centre of a metropolis, selecting as a research area the Ikuno Ward in Osaka city. Ikuno Ward has been losing population since the 1960's (see graph), and it is distinguished by the existence of an important and stable Korean community (a quarter of the total population), whose origin goes back to the colonial times.The data was gathered from the residential change forms in Ikuno's ward office. The study covers the period of March, April and May of 1993, and the subjects are 3, 078 out-migrants and 2, 603 in-migrants, accounting for in each case about 32% of all the migrants from and to Ikuno Ward in that year. The data collected is: gender, type of migration (individual or family), age, and destination or origin of the flows.Out-migration (see Table 1):(1) In both populations out-migrants are short-distance migrants, and about 76% of them moved within the metropolitan area of Osaka. This figure refers to the internal migration. However, the foreigners, who in this case can be considered Koreans, either tend to remain more in the city, mainly in the sourrounding areas where important Korean populations exist, or moved out to the central wards. In addition, there is a significant migration of foreigners to big cities such as Kobe and Kyoto. The outstanding Japanese sectoral bias out-migration toward the east (Nara Prefecture) related to the purchase of a home is unimportant to foreigners, and the suburbanization phenomenon is less evident. At the national level, the foreigners' out-migration to Eastern Japan is far more important than to Western Japan. Therefore they break the East-West cultural division that is visible in the Japanese migration flows.(2) Mobility in terms of gender is substantially higher among men, and more noticeable among Japanese. The sex ratio of out-migrants to the metropolitan area is the same for both populations (about 99), however for the rest of Japan it increases, especially for the Japanese migrating to Eastern Japan.(3) In general, individual migration is higher for foreigners except in the case of the Japanese migrating to Eastern Japan.(4) The Japanese migrants of different ages exhibit clearly different patters of destination choice, while for the Koreans it is not so clear.In-migration (see Table 2) and net migration:There is a negative net migration for both populations. There is a larger percentage of foreigners in-migrating from the metropolitan area, principally from the rest of Osaka Prefecture to Ikuno Ward (positive net migration). The in-migration from Eastern Japan is comparatively higher for foreigners also. For the Japanese, the in-migration from the rest of Western Japan is a major flow (positive net migration). The sex ratio is higher for foreigners particularly for those coming from outside the Metropolitan Area. Ikuno Ward is a net gainer of mainly female, young, individual Japanese migrants from Western Japan.The author believes that the destination choice process varies not only with the migrant's age and gender, but also with its ethnic and cultural characteristics. In this case, restrictions in employment and housing opportunities for Koreans are probably important factors for the difference in migration patterns. Moreover, more qualitative research is needed in geography on the ethnic groups' differential spatial perceptions and migration decision-making process.

Ovarian Cancer Incidence Among Asian Migrants to the United States and Their Descendants

We sought clues to the etiology of ovarian cancer by comparing the incidence rates among Chinese, Japanese, and Filipino migrants to the United States and among their descendants with rates among U.S.-born whites. Information on age, race, and birthplace was obtained for each resident of Hawaii, San Francisco/Oakland, and western Washington identified by the Surveillance, Epidemiology, and End Results (SEER) cancer registry operating in each of those areas with incident ovarian cancer diagnosed during the period from 1973 to 1986. The number of women-years at risk was estimated from a special tabulation of the 1980 census. Among U.S. residents aged 20-79 years, the annual incidence of epithelial ovarian cancer among U.S.-born women of Asian descent was nearly the same as that of women born in Asia (respective annual rates per 100,000: Chinese, 11.7 versus 12.5; Japanese, 11.5 versus 14.1; and Filipino, 8.1 versus 11.0) and was 10%-50% lower than the rate among U.S.-born white women (15.6 per 100,000). For Chinese and Japanese women, this overall pattern with birthplace largely reflected the experience of those aged 50 years and older; in younger women, the rates were somewhat higher among those born in the United States and were similar to those of white women. These findings suggest that some descendants of Asian migrants to the United States retain a factor, genetic or otherwise, that partially protects against the development of ovarian cancer.

Peptic Ulcer Disease Mortality

Peptic ulcer disease mortality patterns of California Japanese are compared with those of their home and host countries for even years from 1960 to 1988, as well as 1989. Data presented are consistent with the hypothesis that Helicobacter pylori is a necessary but not sufficient causal factor in peptide ulcer disease, and that other co-factors including cigarette smoking and salt intake may be important. Deaths due to peptic ulcer numbered 106 among California Japanese, 12,793 for California Caucasians, 107,461 in Japan, and 117,737 for United States Caucasians during the study period. Data for California Japanese were analyzed separately for California Japanese migrants (i.e., those born in Japan) and U.S.-born California Japanese. California Japanese exhibit site-specific peptic ulcer mortality patterns more similar to those of Japan than of the United States. California Japanese migrants (gastric ulcer:duodenal ulcer = 3.2:1), like Japanese in Japan (gastric ulcer:duodenal ulcer = 6.8:1), die more often from gastric than duodenal ulcer, while California and U.S. Caucasians die as often from duodenal ulcer as gastric ulcer (gastric ulcer:duodenal ulcer = 1:1). California Japanese born in the United States exhibit a ratio between those of California Japanese migrants and California Caucasians (gastric ulcer:duodenal ulcer = 2.3:1). U.S.-born California Japanese have the lowest age-adjusted mortality rates for duodenal ulcer and the second-lowest gastric ulcer rates of all populations examined, even though their gastric to duodenal ratio is similar to that for Japan (which has the highest overall ulcer mortality rate).

Cancer risks among European migrants in Sáo Paulo, Brazil

Using both mortality and incidence data, cancer risk in Italian, Spanish and Portuguese migrants to Sáo Paulo were compared with those in the Brazil-born population, and with those in their countries of origin. Italian and Spanish migrants show changes in cancer risks which are rather similar to those observed in migrants of the same origin in other parts of South America: they increase their rates of oropharyngeal, oesophageal, cervical and breast cancers and they decrease their rates of lung cancers. However, for cancer of the oesophagus, the changes are greater in Sáo Paulo, where migrants acquire rates similar to those of the natives. For colon cancer, rates in Italian migrants decrease in the low risk area of Sáo Paulo and increase in the high risk area of Argentina. Changes in Portuguese migrants are less evident: their rates of colorectal cancer remain high, and, as found for Japanese migrants in Sáo Paulo, they also retain their higher risks of stomach cancer.

Increased catechol estrogen metabolism as a risk factor for nonfamilial breast cancer.

The metabolism of estrone (E1) or estradiol-17 beta (E2) to catechols seldom has been investigated in biochemical studies related to the risk of development of human breast cancer, as a result of the extreme lability and reactivity of these hormones. A method of indirect calculation was developed in which estimated catechol estrogen excretion (ECE) from urinary excretion of E1, E2, and estriol (E3) was used, based on the obligate reciprocal relation between 16 alpha-hydroxylase activity (r3) and estrogen 2/4 hydroxylase function (r2). This relationship is expressed by r2 x r3 = K, the estrogen oxidative constant. From published data relating chiefly to 2-OH estrone excretion, K = 12.4 +/- 0.8 (standard error of the mean). Urinary E1 + E2 excretion rates reflect nonprotein-bound plasma ovarian estrogen concentrations available for cell metabolism, which influence the value of K. The equation: r2 = [E1 + E2] K/[E3 + 16 alpha OH E1] = ECE gives a median correlation coefficient between actual catechol estrogen excretion and ECE in micrograms/24 hours of +0.88 (range, 0.61 to 0.97). When tested against the best product isolation analysis of catechol estrogen excretion, ECE was 95% accurate. Using this method a metaanalysis was conducted of published fractional estrogen excretion collected from 2846 healthy women worldwide aged 15 to 59 years, with a risk of breast cancer varying fivefold. Overall ECE was 78% to 97% higher in high-risk women of all ages and menstrual cycle phases (P less than 0.001, by Wilcoxon test). With increasing cancer risk (as estimated by the authors), ECE rose linearly exponentially with a slope of 0.149 (follicular phase) and 0.136 (luteal phase). The correlation coefficient (R2) between the two variables was 0.77 and 0.57, respectively (P less than 0.05). These data derived from calculations of ECE in healthy women confirmed recent analytic results of a twofold increase in the ratio of 2-OH E1/4-OH E1 in healthy Finnish women compared with recent Japanese migrants to Hawaii. In Finnish women with breast cancer, this ratio increased further (almost twofold). Metaanalysis supported the conclusion that increased rates of oxidation of estradiol 17-beta to 2-OH catechols supply the principal proximal human mammary carcinogens active after menarche.

Cancer Incidence in Hawaiian Japanese: Migrants from Okinawa Compared with Those from Other Prefectures

Japanese men in Hawaii whose ancestral roots were in Okinawa were compared to Japanese migrants from all other prefectures. The Okinawan migrants have acquired fewer cancers than men from other prefectures (P=0.12). No one primary site accounts for this difference. Stomach cancer rates showed the largest difference between the two migrant groups. This replicates the experience of Okinawans and non‐Oldnawans in Japan itself. Lymphosarcoma mortality rates are much higher in Okinawa than in all Japan, but this difference is not reproduced in Hawaiian migrants. This could be explained by a post migrational decrease in HTLV‐I‐related acute T‐cell lymphoma/leukemia. Cancer of the mouth, pharynx and esophagus has decreased in all Japanese migrants, but the decrease is much greater among Okinawan migrants, suggesting they have escaped exposure to risk factors peculiar to the Okinawan environment. Colon cancer is more common in migrant Japanese than in U.S. whites. The dramatic increase in the frequency of this tumor affects Okinawan and non‐Okinawan migrants to an equal degree.