METHODS: De-identified patient data from a US electronic health record database (Cerner Real-World Data) was extracted. We included adult (≥18 years) patients who sustained a TBI in 2017. Patients previously diagnosed with depression, a TBI prior to 2017, or another serious neurological event (e.g., stroke, brain tumor, or neurodegenerative disease) were excluded. The incidence of de novo depression was identified by either a diagnosis of a major depressive disorder (via ICD-9/10 codes) or the receipt of an antidepressant or anxiolytic prescription.

RESULTS: A total of 10,399 patients experienced a TBI in 2017, of whom 835 (8%) were diagnosed with de novo depression. The average age of the patients who sustained a TBI was 46.7 years and 57.3% were female. Overall, the incidence of de novo depression decreased with time following a TBI, revealing that 71.3% of patients were diagnosed with depression within Year 1, a further 19.0% by the end of Year 2, and 9.7% in Year 3.

CONCLUSIONS: This study highlights the need for healthcare providers to closely monitor patients who have experienced TBI for de novo depression symptoms, beyond just the first year following a TBI. Future studies should seek to assess additional mental health symptoms to obtain a more comprehensive understanding of the psychiatric complications that can ensue due to TBI.