Pre-existing mental health disorders in patients admitted to the intensive care unit: A systematic review and meta-analysis of prevalence.

This study has demonstrated that patients with pre-existing mental health disorders, particularly depression, constitute a significant subgroup in ICU. Given that the presence of a pre-existing mental health disorder appears to confer an increased mortality risk following ICU discharge, clinicians need to be made aware of this group of patients to provide additional support. Further research is needed to more accurately quantify this vulnerable group and establish methods to enable clinicians to readily identify and refer these patients for appropriate follow-up treatment.