Psychopathy and hormonal biomarkers: a systematic review and meta-analysis

Objective: Psychopathy is often related to disconcerting tendencies and aggressive or violent behavior based on its multiple etiological dispositions. Associations with biomarkers are expected for individuals with psychopathic traits; however, little is known about the relevance of neuroendocrine pathways in explaining psychopathy. A systematic review was conducted to understand to what extent endocrine hormones are related to psychopathy. Also, a meta-analysis was performed on the association between basal cortisol and psychopathy. Method: A systematic review of previous articles that studied the relationship between psychopathy and endocrine biomarkers such as cortisol, testosterone, dehydroepiandrosterone, estradiol, and oxytocin was conducted. Through a database search, 26 articles were included in this systematic review, and seven were included in the meta-analytic procedure, following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. Results: The results of the systematic review supported that psychopathy was related to all biomarkers, but contradictory results were also found. The analysis of the effect sizes at multilevel meta-analysis presented a significant association between baseline cortisol and psychopathy. This study provides information on endocrine hormonal functioning for psychopaths in the development period of early adolescence and adulthood, perceiving these associations in a biopsychosocial sense. Conclusions: The study of these associations and hormonal imbalances can help in the effective evaluation and early identification of psychopathy, offering improvements to deal with the manifestation of psychopathic traits and their implications for the individual, clarifying the role of the neuroendocrine system as an etiological pathway of psychopathy.