Migration and psychosis: a meta-analysis of incidence studies

Abstract

BackgroundThe aims of this meta-analysis are (i) to estimate the pooled relative risk (RR) of developing non-affective psychotic disorder (NAPD) and affective psychotic disorder (APD) among migrants and their children; (ii) to adjust these results for socioeconomic status (SES); (iii) to examine the sources of heterogeneity that underlie the risk of NAPD.MethodsWe included population-based incidence studies that reported an age-adjusted RR with 95% confidence interval (CI) published 1 January 1977–12 October 2017 and used a random-effects model.ResultsWe retrieved studies performed in Europe (n = 43), Israel (n = 3), Canada (n = 2) and Australia (n = 1). The meta-analysis yielded a RR, adjusted for age and sex, of 2.13 (95% CI 1.99–2.27) for NAPD and 2.94 (95% CI 2.28–3.79) for APD. The RRs diminished, but persisted after adjustment for SES. With reference to NAPD: a personal or parental history of migration to Europe from countries outside Europe was associated with a higher RR (RR = 2.94, 95% CI 2.63–3.29) than migration within Europe (RR = 1.88, 95% 1.62–2.18). The corresponding RR was lower in Israel (RR = 1.22; 0.99–1.50) and Canada (RR = 1.21; 0.85–1.74). The RR was highest among individuals with a black skin colour (RR = 4.19, 95% CI 3.42–5.14). The evidence of a difference in risk between first and second generation was insufficient.ConclusionsPositive selection may explain the low risk in Canada, while the change from exclusion to inclusion may do the same in Israel. Given the high risks among migrants from developing countries in Europe, social exclusion may have a pathogenic role.

Social disadvantage, linguistic distance, ethnic minority status and first-episode psychosis: results from the EU-GEI case–control study

“…We showed that a greater frequency of psychotic disorders typically observed in several ethnic minority groups (Selten et al, 2020) may be attributable to markers of social disadvantage and linguistic distance. The latter appeared to have stronger effects in firstgeneration migrants, while the former had greater magnitude amongst second-and later-generation ethnic minority groups.…”

Migration, ethnicity and psychoses: evidence, models and future directions

“…The extent to which rates are elevated, relative to the majority population, varies considerably. For example, the highest reported rates are among Black minority groups (i.e., 4 to 6 times higher than in majority groups). This finding is driven in part by studies from the UK that report especially high rates for Black Caribbean and Black African populations.…”

“…The place of migration may also matter. In the most recent review, for example, there was no strong evidence that rates of psychotic disorders were elevated in migrants to Canada or Israel.…”

Towards a public health approach to psychotic disorders

“…And although the causal mechanisms might not be fully understood, several well established risk factors for psychotic disorders could have important implications for primary prevention, such as social marginalisation and adversity, 11 high-potency cannabis use, 6 and migration. 12 However, assessment of the public health effects of these prevention efforts will not be possible without standardised and consistent metrics for population surveillance of psychotic disorders. Additionally, given the marked heterogeneity observed across countries and contexts, it is unlikely that a one size fits all public health solution will be effective, further highlighting the need for high quality standardised data as an important step towards a public health approach to psychotic disorders.…”