Systematic review: Acculturation strategies and their impact on the mental health of migrant populations

Objectives: This study aims to examine the correlation between the different types of migrant acculturation strategies according to Berry's model of acculturation (integration, assimilation, separation, and marginalisation) and their effects on mental health conditions, such as depression, anxiety and PTSD. Study design: Systematic Review. Methods: Three databases (PubMed, Ovid and Ebsco) were searched using different combinations of search terms to identify relevant articles to be included. The search terms were pre-identified using relevant synonyms for "migrants", "mental health" and "integration". The list of article titles from these searches were then filtered using predefined inclusion and exclusion criteria. The mental health consequences included a range of common conditions including suicide/self-harm, depressive disorders, psychosis, as well as substance misuse. Results: 21 primary studies were included in the review, which assessed 61,885 migrants in total (Fig. 1 and Supplemental File 1). Of these, seven were cohort studies and fourteen were cross-sectional studies. Most studies showed that marginalisation was associated with worse depression symptoms, compared to integration, assimilation and separation, while integration was associated with the least depressive symptoms. Marginalisation more than triples the likelihood of anxiety-related symptoms compared to integration. Similarly, separation increased the likelihood of anxiety-related symptoms nearly six-fold. Conclusions: Our review found out that marginalisation had the worst effects on mental health of the migrant populations while integration had the most positive effects. The study also identified three key sources which may contribute to acculturation stress and worse mental health: low education or skill set, proficiency of the host country's language, and financial hardships.