Predictors of emergency department use for suicidal behaviors among patients with substance-related disorders

Objective: This study aimed to identify predictors of emergency department (ED) use for suicide ideation or suicide attempt compared with other reasons among 14,158 patients with substance-related disorders (SRD) in Quebec (Canada). Methods: Longitudinal data on clinical, sociodemographic, and service use variables for patients who used addiction treatment centers in 2012-13 were extracted from Quebec administrative databases. A multinomial logistic regression was produced, comparing predictors of suicide ideation or attempts to other reasons for ED use in 2015-16. Results: Patients using ED for both suicide ideation and attempt were more likely to have bipolar or personality disorders, problems related to the social environment, 4+ previous yearly outpatient consultations with their usual psychiatrist, high prior ED use, and dropout from SRD programs in addiction treatment centers in the previous 7 years, compared with those using ED for other reasons. Patients with alcohol- or drug-related disorders other than cannabis and living in the least materially deprived areas, urban territories, and university healthcare regions made more suicide attempts than those using ED for other reasons. Patients with common mental disorders, 1-3 previous yearly outpatient consultations with their usual psychiatrist, one previous treatment episode in addiction treatment centers, and those using at least one SRD program experienced more suicide ideation than patients using ED for other reasons. Conclusion: Clinical variables most strongly predicted suicidal behaviors, whereas completion of SRD programs may help to reduce them. SRD services and outreach strategies should be reinforced, particularly for patients with complex issues living in more advantaged urban areas.