Abstract
Alterations in hypothalamic-pituitary-adrenal axis function may underlie the relation between childhood maltreatment and nonsuicidal self-injury (NSSI) behaviors. This study examined how co-occurring patterns of maltreatment types influenced adolescent NSSI behaviors and the mediating role of diurnal cortisol, using a longitudinal design. The sample included 295 Chinese adolescents (M (age) = 10.79 years, SD = 0.84 years; 67.1% boys). The study employed latent profile analysis to identify childhood maltreatment patterns and conducted path analysis to examine the mediating mechanism. Four maltreatment patterns were identified: Low Maltreatment (67.8%), High Neglect (15.6%), Moderate Maltreatment (10.2%), and High Abuse with Moderate Neglect (6.4%). Furthermore, compared to the Low Maltreatment profile, adolescents in the High Neglect profile were at increased risk for later NSSI behaviors through higher waking cortisol levels, while those in the High Abuse with Moderate Neglect profile were at increased risk through a steeper diurnal slope. Disturbances in diurnal cortisol rhythm serve as a pathway through which childhood maltreatment "gets under the skin" to lead to adolescent NSSI behaviors. These findings offer promise for identifying maltreated youth at risk for NSSI behaviors and informing targeted prevention strategies.