Does a North-South gradient exist for ‘healthy immigrant effect’ in Europe?

In recent decades, European countries have experienced a dramatic increase of immigrants from different origins. Therefore health status of immigrants constitutes a genius concern of public health in Europe. Despite this interest, the literature on migrant’s health status remains scare and provides contradictory results. Some studies in Spain, in Canada, and in the USA have shown that immigrants self-reported a better health status than natives, supporting the hypothesis of the “healthy immigrant” effect induced by health selection at migration. Conversely, immigrants report a poorer health status than natives in France, suggesting deleterious effects of acculturation induced by migration and, of poor socioeconomic conditions of migrants in host country. Thus, new studies are needed to properly compare health status of migrants in Europe and to understand the causes of the heterogeneity between European countries. This study proposes to fill this gap by exploring the causes of the heterogeneity of the health gap between migrants and natives in Europe.

This study is based on an innovative pooled dataset from National Health Interview surveys from Belgium, France, Spain and Italy, providing information on self-assessed status, migration status and country of birth, as well as socioeconomic status.

In a first analysis based on probit models, we analyse separately in each of those countries and separately for men and women, the health gap between immigrants versus natives in order to compare the direct effect of migration from the influence of socioeconomic status in host countries and from the influence of countries of birth. As the heterogeneity in health gap between immigrants versus natives between European countries may be due either to differences in health status of migrants between European countries or to difference in natives health status, we propose to compare, in a second step, only immigrants health status between host countries. We use Oaxaca-Blinder decomposition methods in order to explore the causes of differences of health status of immigrants according to host country. We propose in particular to disentangle the heterogeneity explained by differences in observed characteristics of migrants between host countries from the unexplained heterogeneity, which may be attributable either to countries specific factor affecting migrants’ health status, or to differential healthy migrant effects.

Among men, after controlling for socioeconomic status, immigrants report a poorer health status than natives in France, Belgium and Spain than natives, whereas they report a better health status than natives in Italy. Results are quite similar among women except in Spain, where there is no significant difference in health status between migrants and natives.

When the analysis is restrictive to immigrants, a classification in health status could be demonstrated with Italy at the top, followed by Spain, France and with Belgium at the bottom. Decomposition analysis shows heterogeneity in the causes of observed difference in immigrants’ health status across European countries. In Spain, and France differences should be attributable to differences in socioeconomic status and in country of origin. Conversely, immigrant appear to have a better unexplained health status in Italy, and a poorer unexplained health status in Belgium, suggesting the existence of a North-South Gradient in Europe in the healthy immigrant effect.