Schuler KL, et al. - This paper investigated the diathesis-stress model of depression using baseline cortisol, prospective scrutiny of depression symptoms, and stressful life events. The depressogenic effects of stressful events after 18 months were accentuated via blunted cortisol awakening response (CAR) and less daily cortisol output at baseline. This appeared to be consistent with the diathesis-stress model of hypothalamic-pituitary-adrenal axis function in depression.

Methods

• 527 adolescent girls aged 13.5-15.5 years without major depressive disorder were recruited for this trial.
• Saliva samples were obtained at waking, 30 minutes after waking, and 8 p.m. on 3 consecutive days, at baseline.
• Diurnal cortisol was indexed by cortisol awakening response (CAR) and area under the curve with respect to ground (AUCg).
• An evaluation was pursued of the stressful events during the preceding interval and current depressive symptoms, 18 months following baseline.

Results

• The depressive symptoms at 18 months were speculated through the stressful events and the interaction of CAR or AUCg with stressful events, even after controlling for baseline depressive symptoms.
• Owing to the high levels of stress, baseline blunted CAR or smaller AUCg correlated with prospective depressive symptoms.
• This was more pronounced for CAR than AUCg.
• Reversal effect was noted at low levels of stress, with heightened CAR associated with more severe depressive symptoms.