Mental hospital admission rates of immigrants in Switzerland

This epidemiological study aims to assess the utilisation of inpatient psychiatric services by immigrants. Specifically, we address the question of gender-specific differences in immigrants and compare the population-based rates of males and females from different countries of origin.

We analysed inpatient admission rates from a defined catchment area over a 6-year period by means of psychiatric register data. Poisson regression analysis was used to model effects of gender, age and country group (immigrants grouped into six categories according to their country of origin).

Of the total of 28,511 subjects consecutively referred to psychiatric inpatient treatment, 4,814 were foreign nationals (16.9%). Among immigrants the proportion of female inpatients (38.7%) was far lower than in the general population (45.6%; equal proportion of female-to-total among Swiss inpatients). Immigrants were 37.4 years old on average at index admission (Swiss people: 46.3 years), but there were considerable differences across country groups. We found three groups with particularly high admission rates: male immigrants originating from Turkey, Eastern European and 'Other' countries (rates >6 per 1,000 population/year). These were admitted as inpatients at far higher rates than females from the same countries. In women, there was no immigrant group utilising inpatient treatment at a higher level than Swiss females. The rates of inpatient admission in males and females was almost equal among the Swiss (4.3 per 1,000), as was the case for immigrants from Southern, Western/Northern Europe and former Yugoslavia, although on a lower level (2.26-3.15 per 1,000). Regression analysis further suggests that country effects and age effects are different for males and females, and age effects are specific to the country of origin.

These gender- and interaction effects point to inequalities in psychiatric service use in people with different migration background. Further research is needed, particularly to understand the reasons for the markedly different gender-specific utilisation of psychiatric services by some immigrant groups.