The associations between migrant status and ethnicity and the identification of individuals at ultra-high risk for psychosis and transition to psychosis: a systematic review

Purpose Migrant and ethnic minority populations exhibit a higher incidence of psychotic disorders. The Ultra-High Risk for psychosis (UHR) paradigm provides an opportunity to explore the stage at which such factors influence the development of psychosis. In this systematic review, we collate and appraise the literature on the association between ethnicity and migrant status and the rate of identification of individuals at UHR, as well as their rate of transition to psychosis. Methods We conducted a systematic review in the Ovid Medline, PsychINFO, Pubmed, CINAHL and EMBASE databases according to PRISMA guidelines. We included studies written in English that included an UHR cohort, provided a measure of ethnicity or migrant status, and examined the incidence, rate, or risk of UHR identification or transition to psychosis. Results Of 2182 unique articles identified, seven fulfilled the criteria. One study found overrepresentation of UHR individuals from black ethnic groups, while another found underrepresentation. Two studies found increased rates of transition among certain ethnic groups and a further two found no association. Regarding migrant status, one study found that first-generation migrants were underrepresented in an UHR sample. Lastly, a lower transition rate in migrant populations was identified in one study, while two found no association. Conclusion Rates of UHR identification and transition according to ethnic and migrant status were inconsistent and insufficient to conclusively explain higher incidences of psychotic disorders among these groups. We discuss the clinical implications and avenues for future research, which is required to clarify the nature of the associations.