Identifying profiles of people with mental and substance use disorders who use emergency departments may help guide the development of interventions more appropriate to their particular characteristics and needs.

To develop a typology for the frequency of visits to the emergency department for mental health reasons based on the Andersen model.

Questionnaires were completed by patients who attended an emergency department (n = 320), recruited in Quebec (Canada), and administrative data were obtained related to sociodemographic/socioeconomic characteristics, mental health diagnoses including alcohol and drug use, and emergency department and mental health service utilization. A cluster analysis was performed, identifying needs, predisposing and enabling factors that differentiated subclasses of participants according to frequency of emergency department visits for mental health reasons.

Four classes were identified. Class 1 comprised individuals with moderate emergency department use and low use of other health services; mostly young, economically disadvantaged males with substance use disorders. Class 2 comprised individuals with high emergency department and specialized health service use, with multiple mental and substance use disorders. Class 3 comprised middle-aged, economically advantaged females with common mental disorders, who made moderate use of emergency departments but consulted general practitioners. Class 4 comprised older individuals with multiple chronic physical illnesses co-occurring with mental disorders, who made moderate use of the emergency department, but mainly consulted general practitioners.

The study found heterogeneity in emergency department use for mental health reasons, as each of the four classes represented distinct needs, predisposing and enabling factors. As such, interventions should be tailored to different classes of patients who use emergency departments, based on their characteristics.