Research conducted by Seoul National University Bundang Hospital (SNUBH) revealed that trauma from accumulated harm or abuse during childhood period acts as a significant factor in the onset of mental illness in adulthood.

The research team, led by Professor Kim Eui-tae of the Department of Neuropsychiatry at SNUBH, reached this conclusion after analyzing approximately 2,700 participants from Korea and the U.K.

While it is well known that developmental trauma formed through continuous physical, mental, and sexual harm during the childhood period increases the risk of various mental illnesses in adulthood, the clear connection between the two has not been established until now.

Also, cultural and social environmental differences have made it difficult to pinpoint the exact cause.

As a result, the research team conducted a study after hypothesizing that complex PTSD (post-traumatic stress disorder), which arises from developmental trauma, could be the link to mental illnesses in adulthood.

Complex PTSD, caused by persistent trauma, especially during childhood, is characterized by difficulties in emotional regulation, identity confusion, and maintaining relationships, in addition to the symptoms of PTSD.

The study revealed that patients with general PTSD did not exhibit a significant increase in the severity of mental illness compared to the non-PTSD group. In contrast, patients with complex PTSD demonstrated a substantial increase in the severity of mental illness compared to their counterparts.

The findings also indicated that the three characteristics unique to complex PTSD patients - emotional, identity, and relationship maintenance - all exhibited a clear correlation with the severity of mental illness. This suggests that continuous abuse and subsequent trauma during development have a greater impact on the manifestation of mental illness than specific accidents or shocks.

The Korean and U.K. researchers hoped that, given the large populations of both nations involved in the study, the academic community would now accept these findings as established doctrine rather than mere theory.

“Our findings suggest that a public health system that systematically treats and manages patients with childhood trauma could help reduce the incidence of schizophrenia and other mental illnesses,” Professor Kim said. “As the study also confirmed the link to complex PTSD, it is expected to contribute to the development of accurate treatment guidelines.”

The research results were published in the latest issue of The Lancet Psychiatry.