[Mortality among Japanese migrants residing in the municipality of São Paulo, Brazil, 1990].

The mortality patterns of Japanese migrants (issei) and their descendants (nissei/sansei) resident in the City of S. Paulo, Brazil, are compared with those of their native country (Japan) and their place of adoption (S. Paulo), in 1980. The mortality data were obtained from death certificates for the issei and nissei/sansei populations and from official tabulations for deaths in Japan and S. Paulo. The population estimates were based upon the S. Paulo and Japanese censuses. The age-standardized populations were calculated according to the Jowett method. The five leading causes of death were basically the same for these populations under study. S. Paulo residents had the highest age-standardized mortality rates, except as regards deaths due to neoplasms, higher in Japan. The issei population (both sexes) presented intermediate values for deaths due to endocrine, nutritional, and metabolic diseases and diseases of the respiratory system; the female migrants also showed an intermediate rate for deaths due to diseases of the circulatory system. For the other causes, the lowest risk of dying was that registered for the issei population. The comparisons of the rates for cancers of stomach, breast, prostate, diabetes mellitus, ischaemic heart diseases, cerebrovascular diseases, homicide and suicide resulted in the detection of a possible transition experienced by the issei population, leading to the belief that the issei pattern of mortality is showing a deviation from the Japanese pattern and resembles that of S. Paulo. Since social and cultural changes are thought to be occurring among the migrants, one might argue that the role of environmental factors (including diet) is more important than the role of genetic factors in the incidence of and mortality due to these diseases.