Psychiatric comorbidity and trauma: impact on inpatient outcomes and implications for future management

Purpose This study aimed to quantify the impact of pre-existing psychiatric illness on inpatient outcomes after major trauma and to assess acuity of psychiatric presentation as a predictor of outcomes. Methods A retrospective single-center cohort study identified adult trauma patients with an Injury Severity Score (ISS) ≥ 16 between January 2018 and December 2019. Bivariate analysis assessed patient characteristics, injury characteristics, and injury outcomes between patients with and without psychiatric comorbidity. A sub-group analysis explored further effects of psychiatric history and need for inpatient psychiatric consultation on outcomes. Results Of 640 patients meeting inclusion criteria, 99 patients (15.4%) had at least one psychiatric comorbidity. Patients with psychiatric comorbidity sustained distinct mechanisms of injury and higher in-hospital morbidity (44% vs. 26%, OR 1.97, 95% CI 1.17–3.3, p = 0.01), including pulmonary morbidity (31% vs. 21%, p < 0.01), neurologic morbidity (18% vs 7%, p < 0.01), and deep wound infection (8% vs. 2%, p < 0.01) than the control cohort. Psychiatric patients also had significantly greater median intensive care unit (ICU), length of stay (LOS) (1 day vs. 0 days, p = 0.04), median inpatient ward LOS (10 days vs. 7 days, p = 0.02), and median overall hospital LOS (16 days vs. 11 days, p < 0.01). In sub-group analysis, patients with a history of psychiatric illness alone had comparable outcomes to the control group. Conclusions Psychiatric comorbidity negatively impacts inpatient morbidity and inpatient LOS. This effect is most pronounced among acute psychiatric episodes with or without a history of mental illness.