Examining the impact of migrant status on ethnic differences in mental health service use preceding a first diagnosis of schizophrenia

Purpose: Some ethnic groups have more negative contacts with health services for first-episode psychosis, likely arising from a complex interaction between ethnicity, socio-economic factors, and immigration status. Using population-based health administrative data, we sought to examine the effects of ethnic group and migrant status on patterns of health service use preceding a first diagnosis of schizophrenia or schizoaffective disorder among people aged 14–35 over a 10-year period. Methods: We compared access to care and intensity of service use for first-generation ethnic minority groups to the general population of Ontario. To control for migrant status, we restricted the sample to first-generation migrants and compared service use indicators for ethnic minority groups to the European migrant group. Results: Our cohort included 18,080 people with a first diagnosis of schizophrenia or schizoaffective disorder, of whom 14.4% (n = 2607) were the first-generation migrants. Our findings suggest that the magnitude of ethnic differences in health service use is reduced and no longer statistically significant when the sample is restricted to first-generation migrants. Of exception, nearly, all migrant groups have lower intensity of primary care use, and Caribbean migrants are consistently less likely to use psychiatric services. Conclusions: We observed fewer ethnic differences in health service use preceding the first diagnosis of psychosis when patterns are compared among first-generation migrants, rather than to the general population, suggesting that the choice of reference group influences ethnic patterning of health service use. We need a comprehensive understanding of the mechanisms behind observed differences for minority groups to adequately address disparities in access to care.