Abstract
OBJECTIVE: The purpose of this study was to clarify the nature of diurnal salivary cortisol dysregulation in youth who experience posttraumatic stress (PTS). METHOD: Diurnal trends in salivary cortisol secretion were examined in a sample of 41 youth aged 10-16 years (26 youth exposed to interpersonal traumas and 15 control participants with no PTS) using hierarchical linear modeling. RESULTS: Cortisol levels were characterized by curvilinear trends in secretion (i.e., sharp declines from prebreakfast to prelunch followed by smaller decreases from prelunch to predinner with a leveling-off or slight increase from predinner to prebed assessment). Results further indicated that youth with PTS had sharper morning declines and relatively higher evening levels (i.e., a greater curve in the daily trend) than nontraumatized youth. CONCLUSIONS: Findings help to elucidate the physiological basis for altered arousal patterns in youth with PTS. Traumatized youth showed wider daily fluctuations in cortisol levels when these trends were modeled in a curvilinear fashion. The findings help to describe the nature of stress dysregulation in trauma-exposed youth and may have implications for clarifying some of the apparent inconsistencies in the literature.