Aspects of mental and physical health in immigrants in Sweden : an epidemiological study

Abstract

Background: Foreign-born people constitute 12.5% of the Swedish population in Sweden, which calls for further research concerning health outcomes in this population group.

Objectives: To examine the association between country of birth and attempted suicide after accounting for age, marital status, and socioeconomic status (SES) (study 1). To examine the association between country of birth and suicide after accounting for age, marital status, SES and hospitalization for psychiatric disorders or substance abuse (study 2). To examine the association between country of birth and hospital admission for psychotic, affective and neurotic disorders after accounting for age, marital status, and SES (study 3). To examine the possible differences in self-rated health between Finns living in Sweden and Finns living in Finland (study 4).

Methods: In total 4.5 million individuals aged 25-64 were followed from January 1, 1993 until attempted suicide or until December 31, 1998 (study 1). In total 4.4 million individuals aged 25-64 years were followed from January 1, 1994, to December 31, 1999, for suicide (study 2). A two-year national cohort study of 4.5 million individuals in the age group 25-64 years was performed (study 3). National registers including individual demographic and socioeconomic data were linked to the Hospital Discharge Register and the Cause of Death Register and Cox regression was used in the analyses (studies 1, 2, and 3). In study 4, data were obtained from the Swedish Annual Level of Living Survey between 1996 and 2003 and the Finnish national survey Health 2000. Odds ratios (OR) of poor self-rated health were estimated adjusting for age, marital status, education, employment and smoking. The participants were 21991 Swedes and 836 Finns living in Sweden, and 5096 Finns living in Finland (study 4).

Results: Immigrants from Finland, other OECD countries, Poland and Iran had significantly higher risks of attempted suicide than Swedish-born controls. Women born in Latin America, Asia, and Eastern Europe had significantly higher risks of attempted suicide than Swedish-born women. Men born in Southern Europe and Asia had significantly lower risks of attempted suicide. When SES was included in the final model, the risks remained high for women, while the risk of attempted suicide among men declined sharply with increasing income (study 1). Among men the highest risk of suicide was found among men from Finland. Among women the highest risk of suicide was found among women from Finland, Poland, and Eastern Europe (study 2). Several groups of immigrants had higher age-adjusted risks of hospital admission for psychotic, affective, or neurotic disorders than the Swedish controls. After adjustment for SES several of the risks decreased to non-significance among foreign-born men, whereas the risks remained significant among most foreign-born women (study 3). For Finnish women living in Sweden the odds of poor self-rated health were significantly higher than for Finnish women living in Finland. Finnish men living in Finland had higher odds of poor self-rated health than Finnish men living in Sweden, although not to a statistically significant extent (study 4).

Conclusions: Country of birth, SES and gender are associated with attempted suicide, suicide and hospital admissions for mental disorders. Key factors for preventing suicide include early detection and treatment of mental disorders and/or substance abuse, especially among certain groups of immigrants, and among low-income individuals. The effect of migration on Finnish men's and Finnish women's self-rated health may differ. Further studies are needed to investigate the complex pathways underlying these findings.