Why depression in patients with traumatic brain injury is 'hard to treat'

A new study has suggested that patients with depression caused by a traumatic brain injury (TBI) cannot be treated conventionally such as medications and therapy as it is different in people suffering from depression but having no history of TBI.

The research — published in the journal Science Translational Medicine — underlines how depression can be differently treated in different people having TBI with no response to medications and therapy.

"We have believed for a long time that TBI after depression is somehow different, but we have never proven it," said Dr Shan Siddiqi, an assistant professor of psychiatry at Harvard Medical School, who co-led the study.

Dr Jesse Fann, professor of psychiatry and behavioural sciences at the University of Washington School of Medicine, said: "The new research benefited from improvements in imaging technology. Previous research looking at how TBI affects the brain relied on less sensitive brain imaging technology."

Therefore, some of the mental changes that occur after TBI, relating to mood, were overlooked.

The scientists found that despite the same brain circuits' association with depression in both kinds of people, it affected in different ways citing their neural activity.

"This depression is being driven by something different in the brain," said Dr Matthew Peters, an associate professor of psychiatry and behavioural sciences at Johns Hopkins Medicine, who was also with the research.

"People with a TBI are nearly eight times more likely to have depression than people without one. They're also less likely to receive any kind of treatment for depression," Siddiqi stated.

"However, it also may be that traditional depression treatments — medication and psychotherapy — don’t work as well in people with TBI," he remarked.

The research team also stated that a type of therapy called transcranial magnetic stimulation, which stimulates nerves in the brain, could be a promising treatment for depression related to TBI when conventional methods don’t work.

Peters said: "You can both turn on and turn off the neurons that you’re stimulating and for this reason, transcranial magnetic stimulation could offer a more pointed treatment for either overactive or underactive brain circuits."

As researchers explore ways for effective treatment, Fann said: "We cannot think about depression following TBI in the same way as we think about depression in other populations."