Effects of residential changes and time patterns on external-cause mortality in migrants: Results of a German cohort study

Aims: Immigrants are at increased risk of dying from external causes, particularly suicide. This study presents mortality data from a complete follow-up of a cohort of immigrants from the Former Soviet Union to Germany. Number of residential changes after migration and time period between residential change and death are analysed as predictors for suicide and other causes of mortality. Methods: A representative cohort of immigrants (n=34,393) was followed up until 31 December 2002. Residential changes were monitored through city registries. Standardized mortality ratios were calculated for all causes of death and external causes of death (suicides, accidents, other external causes) and deaths attributable to psychoactive substance use. Data on residential change were analysed using Poisson regression to examine differences in external-cause mortality among immigrants who changed residence after immigration. Mortality rates by time since changing residence were calculated, and linear regression analysis was per-formed to model the effect of cause of death on the time interval between residential change and death. Results: Male immigrants had a significantly higher risk of dying from external causes and suicide than Germans, and this increases with frequency of residential changes. Suicide mortality was significantly higher shortly after residential change. Linear regression showed that time to death after residential change was 2.5 times shorter for suicide than for any other cause. Conclusions: High risk of death from external causes and from deaths attributable to substance abuse in immigrants suggests integration problems. Preventive efforts at targeted integration programmes for immigrants, in particular shortly after residential change, are recommended.