Brief report: diurnal salivary cortisol in youth--clarifying the nature of posttraumatic stress dysregulation.

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.