Understanding the role of cannabis in patients with suicidal ideation presenting to the emergency department: systematic chart review

Abstract

Background The association between cannabis use and suicidality has been established, but details on impacts of legalisation, as well as long-term service use, have had limited attention. Aims To examine if changes are present in suicide presentations with access to legal cannabis. Method This study employed administrative database and medical record reviews to identify two cohorts of patients presenting with suicidal ideation/attempts and cannabis use to emergency departments, for two periods: 17 October 2018 to 30 April 2019, and 17 October 2020 to 30 April 2021. Demographic and clinical outcome data were obtained, and emergency department healthcare usage for 2 years before and 2 years after index encounter were compared, to further understand emergency department presentations for the same complaint. Results Number of emergency department encounters following the index visit and number of emergency department encounters specifically relating to suicidality following the index visit were significantly different between cohorts ( t = 2.05, P = 0.042; t = 2.23, P = 0.027, respectively), with the immediate post-cannabis legalisation period demonstrating greater numbers of subsequent emergency department visits for suicidality. Additional associations were found between personality disorders and repeat emergency department visits related to cannabis use. Conclusions There appears to be stability in the patient profile of those presenting to the emergency department with a complaint relating to suicide while reporting cannabis use from the period directly following legalisation in Canada, to a similar time frame 2 years later despite reported increased use of cannabis in the general population over this period. Despite the rising potency and access to legal cannabis, suicide risk remains stable, although concerning.