Effects of pre-existing psychiatric illness on traumatic brain injury outcomes: A propensity-matched cohort study

Abstract

Introduction There are limited data on how patients with pre-existing psychiatric disorders fare after sustaining a traumatic brain injury (TBI). The purpose of this study was to evaluate the impact of pre-existing psychiatric illness on clinical outcomes after TBI. Methods A retrospective review was conducted at a regional level 1 trauma center of patients who suffered a TBI between 2012 and 2020. Propensity scores were used to match patients with psychiatric disorder 1:1 to controls. The matched population was used in analyses. Results Totally, 5343 patients sustained TBI in the study period of which, 977 (18%) had a pre-existing psychiatric disorder. These patients had 1.6 times longer hospital length of stay (LOS) and 1.2 times longer ICU LOS, though days on a ventilator were not longer. TBI readmission, unrelated to the initial head injury, which was more frequent for patients with psychiatric disorder (OR = 2.6 [1.5, 4.6]). Conclusion In patients sustaining a TBI, having a pre-existing psychiatric disorder is an independent risk factor for increased LOS, and TBI readmission. Identifying psychiatric patients as being of higher risk may allow for targeted modifications toward head injury prevention.