Morning salivary dehydroepiandrosterone (DHEA) qualifies as the only neuroendocrine biomarker separating depressed patients with and without prior history of depression: An HPA axis challenge study.

Our study supports that salivary DHEA levels could represent a significant biomarker of MDD progression and individual stress resilience. DHEA deserves additional attention in the research of pathophysiology, staging and individualized treatment of MDD. Prospective longitudinal studies are needed to evaluate HPA axis reactivity along MDD course and progression to better understand temporal effects on stress-system-related alterations, related phenotypes and appropriate treatment.