Cannabis Use and Early Psychiatric Rehospitalization in Young Adults With Bipolar or Psychotic Disorders

In this video overview, Justine Perino, MD, of Nice University Hospital and Université Côte d’Azur, describes an article on cannabis use and time to psychiatric rehospitalization in young adults with bipolar or psychotic disorders. She frames the work as arising from a clinical question: whether cannabis use could be associated with an increased risk of psychiatric rehospitalization after discharge, and whether this risk could change over time.

Perino describes a historical cohort of 200 young adults aged 18 to 29 who were hospitalized for bipolar or psychotic disorders in 2017, with up to five years of follow-up. Information was collected from medical records, including psychiatric history, substance use, and subsequent hospitalizations. She says the analysis used survival analysis and Cox regression models to investigate the association between cannabis use at admission and the timing of psychiatric readmission after discharge.

She reports that cannabis was by far the most commonly used drug in the cohort, with 43% of patients reporting current use, and two-thirds of those reporting daily use. The main finding was that current cannabis use was associated with a 2.8-fold increased risk of psychiatric rehospitalization during the first month after discharge, with the association remaining significant over the first three months but no longer significant after six months or over the full year. Perino also notes limitations, including the retrospective and single-center design, small sample size, and some missing data, and says cannabis use at admission may nevertheless be a marker of a more severe disease course in this population.