Woo et al. (2026)
- Authors: Tae-Wook Woo, Yu-Jin Choi, Jun-Yeol Kim, Jae-Seon Lee, Chang-Gue Son
- Institutes: Liver and Immunology Research Center, Daejeon University, Daejeon, Republic of Korea
- Publisher: Molecular Psychiatry
- Link: DOI
Summary
This comprehensive meta-analysis identifies a definitive ‘hyporeactive’ neuroendocrine signature in ME/CFS, characterized by low available cortisol and a hypersensitive stress-response shut-off mechanism. By reconciling decades of inconsistent findings, the study provides a robust biological basis for hallmark symptoms like unrefreshing sleep, severe fatigue, and impaired stress recovery. These findings distinguish ME/CFS from other conditions and suggest that interventions aimed at restoring endocrine balance could be a vital path for future therapy.
What was researched?
The study performed a large-scale meta-analysis of 46 case-control studies to characterize the function of the hypothalamic-pituitary-adrenal (HPA) axis in patients with ME/CFS.
Why was it researched?
Researchers sought to resolve inconsistent results regarding cortisol levels in ME/CFS and to determine if a consistent neuroendocrine hallmark exists for the disorder.
How was it researched?
The team analyzed data from 1,388 ME/CFS patients and 1,349 healthy controls, evaluating cortisol across saliva, urine, and hair, as well as responses to pharmacological tests like ACTH and glucocorticoid administration.
What has been found?
ME/CFS patients exhibited lower cortisol levels in saliva (at awakening and morning), 24-hour urine, and hair. Additionally, patients showed a blunted response to ACTH 💊 stimulation and an exaggerated sensitivity to glucocorticoid suppression, indicating a chronically underactive endocrine system.
Discussion
The evidence points to a specific ‘hypo-reactivity’ of the stress response system, where the body produces less active cortisol and shuts down its production too easily. This state likely contributes to the cognitive slowing and diminished stress resilience seen in patients.
Conclusion & Future Work
The study concludes that a bioactive cortisol deficit and enhanced feedback sensitivity are core biological features of ME/CFS. These findings support the potential for low-dose hydrocortisone 💊 replacement and other psychobiological interventions to address fatigue syndromes.