During recent decades, much evidence has been accumulated concerning the neuroendocrine basis of schizophrenia. Recently, research has focused on stress hormones, with cortisol being the most widely researched, during the prodromal phase of psychosis. Thus, the present study aims to systematically review the evidence concerning the role of cortisol in patients at risk for psychosis mental state and its associations with psychopathological correlates. We systematically reviewed the published reports referring to both 'at clinical risk for psychosis' and 'at genetic risk for psychosis' mental state. Sixteen studies were identified. A trend towards increased cortisol levels in saliva emerged. Findings concerning cortisol levels in the blood were minimal and less consistent. The longitudinal studies, though with divergent results, hinted towards upregulation of cortisol secretion prior to psychotic conversion. Regarding cortisol's reactivity, evaluated through neuroendocrine, psychosocial and naturalistic stressors, the findings were minimal and divergent. The hypothesized relation of psychotic symptomatology with cortisol in subjects at risk for psychosis was not confirmed by the majority of the studies. On the contrary, the anxiety parameter and stress-intolerance index were both positively associated with cortisol. In conclusion, the published reports related to the evaluation of cortisol levels/function at prodrome are hitherto minimal. Although the evidence favors cortisol's participation in the pathophysiology of psychosis, the exact cause-effect sequence and the intertwining of cortisol with psychopathology are still unclear.
Keywords: cortisol; hypothalamo-pituitary-adrenal axis; psychopathology; psychosis; risk.
© 2014 The Authors. Psychiatry and Clinical Neurosciences © 2014 Japanese Society of Psychiatry and Neurology.