Mortality among 723 948 foreign- and native-born Swedes 1970-1999

Background: Mortality in a population is regarded as an accurate and valid measure of the population's health. There are a few international studies, predominantly cross- sectional, of mortality among all foreign- born compared with an indigenous population, and the results have varied. No Swedish longitudinal study describing and analysing mortality data was found in a literature review. Methods: This study describes and analyses the differences in mortality between foreign- born persons and native Swedes during the period 1970 - 1999, based on data from Statistics Sweden and the National Board of Health and Welfare. The database consisted of 723 948 persons, 361 974 foreign- born living in Sweden in 1970, aged >= 16 years, and 361 974 Swedish controls matched for age, sex, occupation and type of employment, living in the same county in 1970. Results: The results showed increased mortality for foreign- born persons compared with the Swedish controls [ odds ratio ( OR) 1.08; 95% confidence interval ( CI) 1.07 - 1.08]. Persons who had migrated ` late' ( 1941 - 1970) to Sweden were 2.5 years younger at time of death than controls. In relation to country of birth, the highest risk odds were for men born in Finland ( OR 1.21), Denmark ( OR 1.11) and Norway/ Iceland ( OR 1.074). Age cohorts of foreign- born persons born between 1901 and 1920 had higher mortality at age 55 - 69 years than cohorts born between 1921 and 1944. Conclusions: Migrants had higher mortality than the native population, and migration may be a risk factor for health; therefore, this seems to be an important factor to consider when studying mortality and health.