[Click! Health] "High-Risk Depression Can Be Predicted Through Saliva"

Gangnam Severance Professor Seok Jeong-ho's Research Team
Measures Cortisol Levels, a 'Stress Hormone,' in Saliva
Significantly Lower Secretion in High-Risk Groups
"Biological Marker Assessment Possible in Mental Health Domain"

Seok Jeong-ho, Professor of Psychiatry at Gangnam Severance Hospital.

[Asia Economy Reporter Lee Gwan-joo] A study has drawn attention by showing that mental health conditions such as depression can be examined through saliva.

The research team led by Professor Seok Jeong-ho from the Department of Psychiatry at Yonsei University Gangnam Severance Hospital announced on the 7th that they have developed a psychological assessment tool (kit) for comprehensive evaluation of biological, psychological, and social factors related to depression and suicide.

Based on data from 73 participants, the research team classified them into three groups: a mentally healthy group (green group), a depression risk group (red group), and a group on the borderline between illness and healthy state (yellow group).

The team conducted an analysis of salivary cortisol hormone, which can reflect functional changes in the hypothalamic-pituitary-adrenal (HPA) axis of the neuroendocrine system, on the three groups. Saliva samples were collected three times at 30-minute intervals from immediately after waking up in the morning to one hour later, and the cortisol hormone concentration in the saliva was measured.

Comparison graph of post-awakening cortisol secretion according to depression status and resilience.

Cortisol, commonly known as the "stress hormone," increases in secretion when under stress. Cortisol helps maintain blood pressure, balance electrolytes, and promotes energy storage. It also functions as a defense mechanism against stress by enhancing cardiopulmonary activity, enabling quicker and clearer judgment.

The study results showed that the total cortisol concentration after waking in the morning was significantly lower in the depression risk group compared to the mentally healthy group. This suggests that the more severe the depression, the less prepared the body's morning functions are to respond to stress. Additionally, the amount of salivary cortisol increasing within 30 minutes after waking was highest in the group with high resilience compared to the normal or low resilience groups.

Professor Seok Jeong-ho stated, "Until now, in clinical psychiatry, depression diagnosis has been standardly conducted through self-reported depression symptom assessments using questionnaires and clinical consultations. Through this study, it is now possible to evaluate biological markers such as salivary cortisol hormone beyond psychological and social assessment dimensions in diagnosing depression and assessing mental health characteristics, which can enhance scientific objectivity."

The study results were published in the international academic journal ‘Frontiers in Physics’.