OBJECTIVES: Traumatic brain injury (TBI), an acquired injury from sudden trauma, is a major cause of death and disability in the US, often leading to complications like major depressive disorder (MDD). Social determinants of health (SDoH) are non-medical factors influencing overall well-being and contribute to the risk of TBI and depression. We investigated the association between SDoH, COVID-19, and de novo MDD following a TBI and healthcare resource utilization (HCRU).

METHODS: This retrospective study used the National COVID Cohort Collaborative database to identify adult patients (≥18 years) with an index TBI diagnosis based on ICD-10 codes (10/01/2015-01/31/2023). Patients with pre-index diagnosis of MDD or other psychiatric disorders, on antidepressants or anxiolytics were excluded. Associations between gender, race, payer type, COVID-19, and the development of de novo MDD were investigated. All-cause HCRU was assessed at 0.5, 1, 2, and 3 years.

RESULTS: Of the individuals who had a TBI, 15.3% developed de novo MDD (mean age 60). In the MDD cohort, 44.9% were female vs. 32.2% in non-MDD. Significant differences in MDD incidence were found between commercial and public payer types (10% vs.12%, p<0.05), white and black individuals (17% vs. 12%, p<0.01), and males and females (13% vs. 20%, p<0.01). In the MDD cohort, 2.0% were diagnosed with COVID-19 within 6 months post-index compared to 5.2% non-MDD. Higher mean HCRU was observed in the MDD vs. the non-MDD cohort 3 years post-index (149 vs. 108 procedures, 5 vs. 2 ER, 4 vs. 2 inpatient, and 60 vs. 27 outpatient visits), with similar trends at other timepoints.

CONCLUSIONS: Here we show associations between de novo MDD following TBI and payer type, gender, and race alongside increased HCRU after MDD diagnosis, highlighting the need to further study disparities.