Regional differences of death from chronic diseases in Rio Grande do Sul, Brazil from 1970 to 1976

Maps of age adjusted death rates (AADRs) of each health district (HD) in Rio Grande do Sul, the southernmost state of Brazil, for ischemic heart disease, cerebrovascular disease, malignant neoplasm of all sites, esophagus, stomach, colon, lung and breast from 1970 to 1976 are presented. Geographic distribution patterns of these diseases show a strong geographic dependency indicating that environmental factors are important in the etiology of these diseases. Higher AADRs from malignant neoplasms were observed in stock farming areas of the state and from ischemie heart disease and cerebrovascular disease in coast and stock farming areas. AADR from esophagus cancer for males of the state was the highest in the world and for females, it was also one of the highest group. Stomach cancer mortality rate per 100,000 population was about 14.4 through the period of examination and it was about 2.5 times of that of colon cancer in spite of a large quantity of beef consumption. The rank order of AADRs in the world from cancer of digestive tract, from esophagus to rectum, was compared with the rank order of AADRs for the state. This showed a step-down pattern declining from upper to lower tract, and AADR from colon cancer was the same as that of Japan, one of the low risk countries for colon cancer. Higher AADRs from esophagus and stomach cancer might be due to very hot “mate-tea” (infusion of Ilex paraguayensis A. St. Hil.) and a large salt intake, especially in stock farming areas. Rapid increase of AADRs from lung and breast cancer were also observed and they showed a similar geographic distribution. Further studies on the environmental factors associated with AADRs from above mentioned diseases are needed.