Ethnic and migrant group differences in psychosis treatment

Background: Over the past three decades, studies have consistently highlighted ethnic and migrant differences in psychosis risk, treatment, and outcomes in the Global North. Receipt of evidence-based treatment for psychosis is of particular importance, as timely and appropriate care is crucial for recovery and forms the ethos behind the development of Early Intervention in Psychosis services. Despite its importance, the extent of ethnic and migrant differences in psychosis care and possible associated factors remain unclear. My thesis investigates differences in psychosis treatments across migrant and ethnic minority groups and the role of income, clinical, and contextual variables on treatment outcomes. Methods: Following an introductory chapter and a statement of aims (Chapters 1–2), I conducted a systematic review (Chapter 3) on ethnic and migrant differences in psychosis treatment, which informed the design of three quantitative studies using two separate datasets. Using Swedish population-based registry data (described in Chapter 4), I conducted two studies examining migrant differences in antipsychotic treatment (Chapter 5) and psychotherapy receipt (Chapter 6) among individuals with first-episode psychosis. For my third study I used Electronic Health Records from Camden and Islington NHS Trust (described in Chapter 7) to examine ethnic differences in antipsychotic prescribing and psychotherapy receipt within EIP services (Chapter 8). For all studies I assessed the potential effect of income, contextual and clinical variables (as proxies for severity) on the relationship between migrant status/ethnic group and treatment outcomes using logistic or Cox regression modelling. Results: My findings revealed variations in treatment receipt across migrant and ethnic minority groups. Key findings included: (1) decreased receipt of any antipsychotic treatment, antipsychotic polypharmacy and Clozapine in migrants; (2) increased receipt of first-generation antipsychotics and long-acting injectable antipsychotics in some migrant and ethnic minority groups, and; (3) little evidence of differences in psychotherapy receipt by migrant status. Treatment disparities varied by migrant status, region of origin, parental migration background, and specific ethnic groups. For instance, refugee migrants were less likely to receive antipsychotic polypharmacy compared with Swedish-born individuals (aOR: 0.38, 95% CI: 0.74–0.93). First-generation antipsychotic use was higher in children of two migrant parents (aOR: 1.22, 95% CI: 1.07–1.38) and those with one migrant parent (aOR: 1.10, 95% CI: 1.00–1.20) compared with those without a migrant background. In the UK sample, Black ethnic groups had a higher risk of receiving long-acting injectables than White groups (aHR: 1.57, 95% CI: 1.10–2.25), while no such differences were observed for other ethnic groups. Across all studies, disparities persisted after adjusting for clinical and contextual covariates. Conclusion: My thesis provides a comprehensive analysis of psychosis treatment disparities by migrant status and ethnicity across two national contexts. My findings revealed persistent inequities in care and distinct treatment patterns across and within migrant and ethnic minority groups. These disparities remained after accounting for key confounders, underscoring the need for more nuanced, equity-focused approaches to psychosis care and policy, and research that considers broader determinants of psychosis care.