Salivary markers of violence - the possible alterations in salivary cortisol levels to identify victims of violence - a systematic review

Each form of violence constitutes a significant social problem and presents a diagnostic challenge, particularly from the perspective of medico-legal assessment. Moreover, as a stressor, violence influences the levels of biomarkers that can be measured in saliva, an easily accessible material for testing. This systematic review aimed to assess changes in salivary hormonal biomarker levels among individuals experiencing various forms of violence, with particular emphasis on cortisol. Following the established inclusion and exclusion criteria, 22 studies were included. Most studies originated from Europe and the USA and encompassed both children and adults. Cases of interpersonal violence were analyzed, particularly physical, sexual, and psychological violence, including bullying. Based on the analysis of the included studies, trends in alterations of salivary cortisol levels and its diurnal secretion profile were identified. The conducted meta-analysis demonstrated slightly lower morning cortisol levels and significantly elevated evening cortisol levels in abused individuals. Further research is necessary to precisely characterize the impact of violence on salivary cortisol levels to evaluate the potential use of this parameter for the objective, real-time diagnosis of violent events. Such advancements would facilitate the implementation of victim care programs and enhance the detection of violence.