The successful integration of the high numbers of refugees is one of the most critical issues facing the EU today. We will identify factors at the neighbourhood- , family- , peer- , and individual-levels that may protect immigrant children, adolescents and adults from psychiatric disorders, substance use disorders, and crime. We have access to highly accurate and almost complete nationwide sociodemographic data from 1960-2018 including, but not limited to, country of birth, education, income, employment, and social welfare, school grades, and reason for immigration linked to nationwide inpatient- and outpatient health care data, family relations, neighbourhood socioeconomic factors and indices of 250,000 neighbourhood goods and services. These timely data are available for more than 3 million 1st and 2nd generation immigrants, including over half a million more recent immigrants from the Middle East and Africa.
Conclusions: We identified factors at the neighbourhood- , family- , peer- , and individual-levels that seem to protect immigrant children, adolescents and young adults from psychiatric diseases, substance use disorders, and crime. For example, neighbourhood immigrant composition is associated with risk of officially-recognised drug involvement (ORDI), with differential associations for immigrants and native-born populations. This novel open cohort study is the first to use data from a nationwide primary health care data source - to compare the incidence of major depressive disorder (MDD) among immigrants aged 15-39 years with natives in Sweden using clinical data from primary health care, where most cases of MDD are diagnosed. Second-generation immigrants seem to be at a particularly high risk of MDD. An examination of both sexes and two different proxies for acculturation provides consistent support for socio-cultural influences on AUD risk. Our co-sibling analyses suggest that a meaningful proportion of this effect is likely to be causal in nature. Parental high socio-economic status (SES) and/or absence of parent psychiatric illness have a reduced protective effect on immigrant youth compared to non- immigrant youth. In addition, the protective effects of parental education and employment were weaker for immigrant youth compared to native-born youth. Acculturation and integration into the society are relevant not only for the well-being and health of immigrants. We also found that there also seems to be a potential influence of a successful integration on the odds of rape; these novel findings suggest that societal interventions may decrease rates of certain crimes among immigrants.