Facing trauma in childhood can significantly change the structure of the brain, which may result in severe depression which could even be recurrent in adulthood, say researchers.
The results from MRI scan images suggest that both childhood maltreatment and recurring depression are associated with similar reductions in the surface area of the insular cortex, part of the brain that regulates emotion and self-awareness.
This reduction in the brain could make a future relapse more likely, said the study, published in The Lancet Psychiatry journal, which found childhood maltreatment one of the strongest risk factors for major depression in adulthood.
"Given the impact of the insular cortex on brain functions such as emotional awareness, it's possible that the changes we saw make patients less responsive to conventional treatments," said lead researcher Nils Opel from the University of Munster in Germany.
The study included 110 patients aged 18 to 60 years. Of the 75 patients who experienced a relapse, 48 had experienced one additional episode, seven reported two episodes and six experienced three episodes.
Fourteen had a remission period of fewer than two months and could, therefore, be regarded as having chronic depression.
The findings are to develop or improve risk-adapted interventions for people susceptible to a worse long-term clinical outcome.
Future psychiatric research should, therefore, explore how the findings could be translated into special attention, care and treatment that could improve patient outcomes, the study noted.