Background Describing the health status of migrants poses a real challenge, especially when it comes to mental health, which is heavily stigmatized and stereotyped. Belgium, which underwent an important mental health reform in 2010, is a good case study for analysing how the prevalence of mental health distress has evolved over time and how that evolution had differed between migrants and non-migrants.

This paper describes the prevalence of psychological distress among migrants and ethnic minorities in Belgium since 1997 and the different factors that contribute to the difference between this group and the general population. One of the main objectives is to describe the inequalities in the prevalence of mental health risk according to ethnicity, socio-economic status, age, and gender, and to identify the protective factors for mental health problems.

Methods The data set is composed of the six cross-sectional waves of the Belgian ‘Health Interview Survey’ from 1997 to 2018. The 12-item General Health Questionnaire score was used to measure the prevalence of psychological distress among five major migrant/ethnic groups in Belgium (Belgian, Moroccan, Turkish, European migrants, and non-European migrants). Socio-economic status was assessed based on employment status, income, and level of education. We also used demographic variables such the age and sex of the respondents to identify the protective factors for mental health problems. All the statistical analyses were performed using SAS 9.4.

Results Preliminary results revealed that, since 1997, there has been a difference in the prevalence of mental health distress between ethnic groups, especially in 2013 and in 2018. During those two years, the risk of psychological distress increased significantly among Moroccan and Turkish respondents, in comparison with other ethnic groups (χ2(2013) =36,93, p<0001 and χ2(2018) =13,46, p<05, respectively).

Conclusion This study provided an overview of the evolution of the prevalence of mental health distress among five major ethnic groups in Belgium. We believe that more research is needed on mental health among migrant and ethnic minority groups so that healthcare can be tailored to respond to their needs. In order to provide healthcare that is more sensitive to the needs of diverse groups, we recommend that future research on ethnic mental healthcare includes data collection on the cultural background of patients. We found that age, sex and employment status were risk factors for mental health distress.