(1550) Association of Mental Disorders and Short-Term Mortality in Traumatic Brain Injury Hospitalizations

Introduction: Mental disorders are associated with lower life expectancy and increase the risk of traumatic brain injury (TBI). Data on the prognostic impact of mental disorders on TBI is limited and inconclusive

Methods: We used publicly available, statewide, and deidentified hospitalization records to study trauma and emergency hospitalizations aged ≥18 years with a principal diagnosis of initial encounter for TBI admitted to acute care hospitals in Texas for years 2016 through 2021. Mental disorders were identified using International Classification of Diseases, Tenth Revisions, Clinical Modification (ICD-10-CM) codes and included mood disorders, anxiety disorders, personality disorders, and schizophrenia and other psychotic disorders. Three models estimated the association between mental disorders in-hospital mortality. Multilevel logistic regression with propensity adjustment was the primary analysis approach with propensity score matching and multivariable logistic regression without propensity score matching applied as alternative analyses. Additional analyses were completed for subgroups, sensitivity for more severe cases, categories of mental disorders, and for the secondary outcome of short-term mortality.

Results: Out of 76,739 emergency and trauma hospitalizations with a principal diagnosis for TBI, 13,760 (17.9%) had mental disorders. TBI hospitalizations with vs without mental disorders were more often female (58.4% vs 40.8%), more often white (67.1% vs 53.7%), and had higher Deyo Comorbidity Index (mean [SD] 1.49 [1.86] vs 1.11[1.70]); p < 0.0001 for each. Unadjusted in-hospital mortality among TBI hospitalizations with vs without mental disorders was 4.9% vs 9.6%. On adjusted analyses, mental disorders remained associated with lower odds of in-hospital mortality (adjusted odds ratio 0.6270 [95% CI 0.5582–0.7042]). The results were similar for the alternative modeling approaches, subgroup analyses, sensitivity analyses, categories of mental disorders, and for short-term mortality.

Conclusions: Mental disorders were associated with lower risk of in-hospital mortality in hospitalizations with a principal diagnosis of a TBI. Additional studies exploring the mechanisms leading to these findings can improve understanding of TBI pathology.