Ethnic inequalities in the incidence of diagnosis of severe mental illness in England: a systematic review and new meta-analyses for non-affective and affective psychoses

Purpose Although excess risks particularly for a diagnosis of schizophrenia have been identified for ethnic minority people in England and other contexts, we sought to identify and synthesise up-to-date evidence (2018) for affective in addition to non-affective psychoses by specific ethnic groups in England. Methods Systematic review and meta-analysis of ethnic differences in diagnosed incidence of psychoses in England, searching nine databases for reviews (citing relevant studies up to 2009) and an updated search in three databases for studies between 2010 and 2018. Studies from both searches were combined in meta-analyses allowing coverage of more specific ethnic groups than previously. Results We included 28 primary studies. Relative to the majority population, significantly higher risks of diagnosed schizophrenia were found in Black African (Relative risk, RR 5.72, 95% CI 3.87–8.46, n = 9); Black Caribbean (RR 5.20, 95% CI 4.33–6.24, n = 21); South Asian (RR 2.27, 95% CI 1.63–3.16, n = 14); White Other (RR 2.24, 95% CI 1.59–3.14, n = 9); and Mixed Ethnicity people (RR 2.24, 95% CI 1.32–3.80, n = 4). Significantly higher risks for diagnosed affective psychoses were also revealed: Black African (RR 4.07, 95% CI 2.27–7.28, n = 5); Black Caribbean (RR 2.91, 95% CI 1.78–4.74, n = 16); South Asian (RR 1.71, 95% CI 1.07–2.72, n = 8); White Other (RR 1.55, 95% CI 1.32–1.83, n = 5); Mixed Ethnicity (RR 6.16, 95% CI 3.99–9.52, n = 4). Conclusions The risk for a diagnosis of non-affective and affective psychoses is particularly elevated for Black ethnic groups, but is higher for all ethnic minority groups including those previously not assessed through meta-analyses (White Other, Mixed Ethnicity). This calls for further research on broader disadvantages affecting ethnic minority people.