The size and diversity of present day global human mobility have significant implications for population health. According to the United Nations, there are around 214 million people crossing borders to live in countries other than those they were born in, and more than three times this number moving within countries. Migrants, whether workers, students, refugees, asylum seekers, undocumented, or family members, like people in both sending and receiving countries who do not migrate, are characterised by diverse factors affecting their health status and health needs. It is also important to recognise that the relationship between migration and health is a two way process. While it is more commonly considered that migration impacts on people’s health, health is also implicated in migration motivations and processes – for example, it plays a part in determining who is allowed into or out of a country.
There are two broad interrelated considerations that are important in thinking about migrants’ health. The first has to do with what are the determinants of migrants’ health, while the second relates to the scope within which the health of migrants is considered, that is, going beyond a receiving country perspective to include the entire migration process.
Generally, social – as distinct from genetic or biological – determinants of people’s health refer to the impact of social factors on health outcomes, or on health inequalities/disparities between different groups. Traditionally, the focus has been on an observed socio-economic gradient in health, whether measured by individual socio-economic position or social class, or by area deprivation indicators: for instance, higher and widening obesity rates over time among men and women in unskilled manual jobs compared to those in professional jobs in England; and higher rates of premature mortality for cancer, heart attacks, strokes, lung disease and liver disease in areas of social deprivation (Marmot et al., 2010). Considering ethnicity or migration variables (for example, country of birth, length of residence in the receiving society and legal status) in relation to socio-economic factors in health outcomes complicates the picture. As critics have pointed out, simply conflating, say, ethnicity and social class on the basis that once social class is adjusted for in analysis, ethnic inequalities in health often disappear or are reduced, fails to fully unravel the relationship between ethnic (or country of birth) differences, socio-economic position, and health inequalities (Lorant and Bhopal, 2011). In exploring the social determinants of migrants’ health and health inequalities, studies have shown that it is imperative to consider, both conceptually and empirically, the interaction (intersectionality) between a variety of factors affecting health status, health behaviour, and access to healthcare, including:
- Demography – for example, sex, age, age at migration and life cycle stage;
- Socio-economic position – for example, educational and occupational background and present circumstances, income, housing and living situation;
- Place – not just level of area deprivation, but also the importance of social support provided by co-ethnics in the locality: the ‘ethnic density effect’ (see Pickett and Wilkinson, 2008);
- Immigration and integration policies – for example, rules governing entry, access to health and other services, and to economic and social opportunities which impact on health;
- Direct and indirect racism and discrimination;
- Ethnic and cultural background – including religion, languages and health-related practices;
- Migration histories – including sending contexts (see below), length of residence in receiving societies, and transnational connections.
Social determinants of migrants’ health should not be viewed simply from a receiving society perspective. All stages of the migration process – pre-departure, migration journeys, destination, return to sending countries/areas – contribute determining factors for migrants’ physical and mental health, and health and social protection (Zimmerman et al., 2011). The ‘healthy migrant effect’, linking sending and receiving contexts, is one framework that is used in some studies. It explores selectivity in the migration of healthier people that is associated with positive health outcomes, which in turn change/deteriorate over time as migrants adopt ‘risky’ health behaviours (for example smoking patterns or diet) characteristic of receiving society populations, which are associated with a high prevalence of non-communicable diseases, such as heart disease, stroke and diabetes among some first and second generation ethnic minority groups. However, other evidence has challenged the explanatory value of linear health ‘acculturation’ models, which do not take into account the complexity of social determinants, including structural constraints in achieving healthy life styles, health behaviour and disease patterns in countries of origin, and the pre-migration health status of those who migrate, in understanding patterns of migrants’ health over time (Jayaweera and Quigley, 2010).
Overall, evidence suggests that a comprehensive understanding of migrants’ health must be based on a conceptual framework that explores the dynamic interaction of a variety of social determinants within a context that encompasses the entire migration process from origins to destinations and back again.
Jayaweera, H. and Quigley, M. (2010) ‘Health Status, Health Behaviour and Healthcare Use Among Migrants in the UK’, Social Science & Medicine, 71(5): 1002-10.
Lorant, V. and Bhopal, R. (2011) ‘Ethnicity, Socio-Economic Status and Health Research: Insights from and Implications of Charles Tilly’s Theory of Durable Inequality’, J Epidemiol Community Health, 65(8): 671-5.
Marmot, M. et al. (2010) ‘Fair Society, Healthy Lives’, The Marmot Review, UCL Insitute of Health Equity, London.
Pickett, K. and Wilkinson, R. (2008) ‘People Like Us: Ethnic Group Density Effects on Health’, Ethnicity & Health, 13(4): 321-34.
Zimmerman, C. et al. (2011) ‘Migration and Health: A Framework for 21st Century Policy-making’. PLos Medicine, 8(5).