Depression that develops after traumatic brain injury may be clinically distinct from other depressive disorders, new research by Brigham and Women’s Hospital and collaborators suggests.
Brain circuitry differed with this type of depression compared with others, leading researchers to suggest it should be treated as a distinct “TBI affective syndrome.”
Reporting in Science Translational Medicine, the team suggests these patients could benefit from individualized neuromodulation approaches that target its distinct neural circuitry.
“This study illustrates how cutting-edge personalized brain mapping technology can help us find disease patterns that were previously undetectable,” researcher Shan Siddiqi, MD, from Brigham and Women’s Hospital department of psychiatry, told Inside Precision Medicine.
“We are now working on applying these personalized medicine techniques to target precision brain stimulation treatment.”
Depression affects nearly half of all people with traumatic brain injury, and several key differences have previously been noted between these patients and those with primary major depressive disorder (MDD).
For example, depression after traumatic brain injury is associated with impulsivity and aggression, with less of the apathy seen with typical primary MDD. It also tends not to respond to conventional antidepressant medication and psychotherapy.
The current study led on from a small clinical trial that deployed recent advances in resting-state functional magnetic resonance imaging (fMRI) to map connectivity between different brain networks among individual patients.
That trial by Siddiqi and co-workers used personalized brain mapping to undertake targeted transcranial magnetic stimulation (TMS) and revealed specific patterns in the brain abnormalities of patients with depression after traumatic brain injury.
In the current retrospective, cross-sectional analysis, the team analyzed 273 patients in previously published studies who underwent fMRI and had traumatic brain injury with or without depression, depression without traumatic brain injury, or none of these disorders.
Overall, 93 patients from four discovery cohorts and 180 from a large replication cohort were studied in order to determine the distinct architecture in brain networks that was associated with depression after traumatic brain injury.
The study revealed that depression after traumatic brain injury was associated with decreased dorsal attention network (DAN)–subgenual cingulate connectivity, increased DAN- default mode network connectivity, and the combined effect of both.
“If the underlying pathophysiology is related to connectivity rather than neurochemical or psychological factors, these patients may be more appropriate for structurally oriented treatments,” the researchers speculate.
“For instance, targeted TMS has demonstrated preliminary efficacy for [traumatic brain injury]-associated depression in a pilot clinical trial.”
They add: “In combination, these methods have the potential to redefine our approach to personalized medicine in the management of neuropsychiatric sequelae of [traumatic brain injury].”
