Emergency department visits and use of outpatient physician services by adults with developmental disability and psychiatric disorder.

OBJECTIVE: To compare the emergency department (ED), primary, and psychiatric care visit rates associated with the presence and absence of a developmental disability (DD) and a mental illness.
METHOD: This is a population-based study comparing Ontario adults, with and without DDs and mental illnesses, in terms of rates of primary, psychiatric, and ED care, from April 2007 to March 2009.
RESULTS: In Ontario, 45% of adults with a DD received a psychiatric diagnosis during a 2-year period, and 26% of those with a psychiatric diagnosis were classified as having a serious mental illness (SMI), compared with 8% of those with a psychiatric diagnosis but no DD. People with DDs had an increased likelihood of psychiatric and ED visits. Patients with SMIs and DDs had the highest rates of such visits.
CONCLUSIONS: People with more severe impairments had the greatest likelihood of ED visits, despite access to outpatient services, suggesting that outpatient care (primary and psychiatric), as currently delivered, may not be adequate to meet their complex needs.