TBI-associated depression may be a different disease process , leading the study authors to propose a new name : “ TBI affective syndrome .”
Depression After Traumatic Brain Injury Could Represent a New , Distinct Disease
A new study led by Shan Siddiqi , MD , from Brigham and Women ’ s Hospital , a founding member of the Mass General Brigham healthcare system , suggests that depression after traumatic brain injury ( TBI ) could be a clinically distinct disorder rather than traditional major depressive disorder , with implications for patient treatment . The findings are published in Science Translational Medicine .
“ Our findings help explain how the physical trauma to specific brain circuits can lead to development of depression . If we ’ re right , it means that we should be treating depression after TBI like a distinct disease ,” said corresponding author Shan Siddiqi , MD , of the Brigham ’ s Department of Psychiatry and Center for Brain Circuit Therapeutics . “ Many clinicians have suspected that this is a clinically distinct disorder with a unique pattern of symptoms and unique treatment response , including poor response to conventional antidepressants – but until now , we didn ’ t have clear physiological evidence to prove this .”
Siddiqi collaborated with researchers from Washington University in St . Louis , Duke University School of Medicine , the University of Padua , and the Uniformed Services University of the Health Sciences on the study . The work started as a side project seven years ago when Siddiqi was motivated by a patient he shared with David Brody , MD , PhD , a co-author on the study and a neurologist at Uniformed Services University . The two started a small clinical trial that used personalized brain mapping to target brain stimulation as a treatment for TBI patients with depression . In the process , they noticed a specific pattern of abnormalities in these patients ’ brain maps .
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The current study included 273 adults with TBI , usually from sports injuries , military injuries , or car accidents . People in this group were compared to other groups who did not have a TBI or depression , people with depression without TBI , and people with posttraumatic stress disorder . Study participants went through a resting-state functional connectivity MRI , a brain scan that looks at how oxygen is moving in the brain . These scans gave information about oxygenation in up to 200,000 points in the brain at about 1,000 different points in time , leading to about 200 million data points in each person . Based on this information , a machine learning algorithm was used to generate an individualized map of each person ’ s brain .
The location of the brain circuit involved in depression was the same among people with TBI as people without TBI , but the nature of the abnormalities was different . Connectivity in this circuit was decreased in depression without TBI and was increased in TBI-associated depression . This implies that TBI-associated depression may be a different disease process , leading the study authors to propose a new name : “ TBI affective syndrome .”
“ I ’ ve always suspected it isn ’ t the same as regular major depressive disorder or other mental health conditions that are not related to traumatic brain injury ,” said Brody . “ There ’ s still a lot we don ’ t understand , but we ’ re starting to make progress .”
One limitation of the trial is that with so much data , the researchers were not able to do detailed assessments of each patient beyond brain mapping . As a future step , investigators would like to assess participants ’ behavior in a more sophisticated way and potentially define different kinds of TBI-associated neuropsychiatric syndromes .
Siddiqi and Brody are also using this approach to develop personalized treatments . Originally , they set out to design a new treatment in which they used this brain mapping technology to target a specific brain region for people with TBI and depression , using transcranial magnetic stimulation ( TMS ). They enrolled 15 people in the pilot and saw success with the treatment . Since then , they have received funding to replicate the study in a multicenter military trial .
“ We hope our discovery guides a precision medicine approach to managing depression and mild TBI , and perhaps even intervene in neuro-vulnerable trauma survivors before the onset of chronic symptoms ,” said Rajendra Morey , MD , a professor of psychiatry at Duke University School of Medicine , and co-author on the study . g
TBI-associated depression may be a different disease process , leading the study authors to propose a new name : “ TBI affective syndrome .”