Trends in mental health service utilisation in immigrant youth in Ontario, Canada, 1996-2012: a population-based longitudinal cohort study.

Objective: To describe trends in mental health service use of youth by immigration status and characteristics.

Design: Population-based longitudinal cohort study from 1996 to 2012 using linked health and administrative datasets.

Setting: Ontario, Canada.

Participants: Youth 10-24 years, living in Ontario, Canada.

Exposure: The main exposure was immigration status (recent immigrants vs long-term residents). Secondary exposures were region of origin and refugee status.

Main Outcome Measure: Mental health hospitalisations, emergency department (ED) visits and outpatient visits within consecutive 3-year time periods. Poisson regression models estimated rate ratios (RR).

Results: Over 2.5 million person years per period were included. Rates of recent immigrant mental health service utilisation were at least 40% lower than long-term residents (p<0.0001).Mental health hospitalisation and ED visit rates increased in long-term residents (hospitalisations, RR 1.09 (95% CI 1.08 to 1.09); ED visits, RR 1.15 (1.14 to 1.15)) and recent immigrants (hospitalisations RR 1.05 (1.03 to 1.07); ED visits, RR 1.08 (1.05 to 1.11)). Mental health outpatient visit rates increased in long-term residents (RR 1.03 (1.03 to 1.03)) but declined in recent immigrant (RR 0.94 (0.93 to 0.95)). Comparable divergent trends in acute care and outpatient service use were observed among refugees and across most regions of origin. Recent immigrant acute care use was driven by longer-term refugees (hospitalisations RR 1.12 (1.03 to 1.21); ED visits RR 1.11 (1.02 to 1.20)).

Conclusions: Mental health service utilisation was lower among recent immigrants than long-term residents. While acute care use is increasing at a faster rate among long-term residents than recent immigrants, the decrease in outpatient mental health visits in immigrants highlights a potential emerging disparity in access to preventative care.