Cumulative Childhood Maltreatment and Non-Suicidal Self-Injury: the Mediating and Moderating Role of Perceived Social Support in a Sample of University Students

Non-suicidal self-injury (NSSI) in young adults is recognized as a major public health concern. Some studies have identified cumulative childhood maltreatment (CCM) as a significant vulnerability factor for NSSI, although the nature of this association remains unclear. Specifically, some theorists have investigated the role of perceived social support (PSS), considered an important factor closely associated with both CCM and NSSI. The aim of the current study was to simultaneously investigate the potential mediating and moderating role of PSS from family and friends in the association between CCM and NSSI in a university student sample. Participants were 474 students (73.4% female; Mage = 21.61, SD = 1.92) attending a state university in southern Italy (Sicily) who completed self-report questionnaires regarding childhood trauma, non-suicidal self-harming behaviors, and PSS. The mediation model showed that CCM was significantly and positively linked to NSSI through perceived support from family, so that the higher the CCM, the lower the perceived support from family and, consequently, the higher the presence of NSSI behaviors. Moreover, the moderating model indicated that perceived support from friends buffered the relation between CCM and NSSI. These findings expand our understanding of the role of PSS in the relation between CCM and NSSI. Specifically, the perception of family support may be affected by early maltreatment experiences, increasing the risk of NSSI (mediation), whereas it seems that perceived friends support operates as a stress buffer, mitigating the deleterious effects of CCM on NSSI (moderation). Methodological limitations and clinical implications of the study are discussed.