PTSD and depressive symptoms are linked to DHEAS via personality

•DHEAS level is lower in subjects with PTSD than in trauma controls.•DHEAS is related to PTSD and depressive symptoms via personality trait Disintegration.•Personality traits predict mental illness. Research results on dehydroepiandrosterone sulfate ester (DHEAS) in post-traumatic stress disorder (PTSD) are inconsistent. We hypothesized that personality traits could be the confounders of DHEAS levels and disease symptoms, which could in part explain the discrepancy in findings. This study was a part of a broader project in which simultaneous psychological and biological investigations were carried out in hospital conditions. 380 male subjects were categorized in four groups: A) current PTSD (n = 132), B) lifetime PTSD (n = 66), C) trauma controls (n = 101), and D) healthy controls (n = 81), matched by age. The level of DHEAS is significantly lower in the current PTSD group than in trauma controls. All groups significantly differ in personality traits Disintegration and Neuroticism (current PTSD group having the highest scores). DHEAS is related to both PTSD and depressive symptoms; however, Structural Equation Model (SEM) shows that the relations are indirect, realized via their confounder – personality trait Disintegration. According to our project results, DHEAS is the second putative biomarker for trauma-related disorders that fails to fulfil this expectation. It appears to be more directly related to personality than to the disease symptoms (the first one being basal cortisol). Our data promote personality as a biologically based construct with seemingly important role in understanding the mental health status.