Cortisol secretion in depressed, and at-risk adults

Distinct patterns of cortisol secretion have been associated with depression in past research, but it remains unclear whether individuals at-risk for depression may also have similar patterns of cortisol secretion. This is the first study to date of both naturalistic diurnal cortisol secretion and cortisol reactivity to a psychosocial laboratory stressor in depressed and at-risk adults. Cortisol secretion patterns were compared for 57 currently depressed, at-risk (based on trait-level positive and negative affect), and control participants over 5 days and in response to a laboratory stressor. After controlling for potentially confounding biobehavioral variables, the depressed group had a larger cortisol awakening response (CAR) and higher average diurnal cortisol compared to control participants. Individuals at-risk for depression also had significantly higher waking cortisol levels than control participants. Results for the psychosocial laboratory stressor did not show the predicted elevations in cortisol for depressed and at-risk participants compared to controls. The at-risk group recovered more quickly when compared to the depressed group both in levels of cortisol and concurrent measures of negative affect. The at-risk and depressed participants were similar on the diurnal cortisol measures, but differed on response to the laboratory social stressor, suggesting divergence in cortisol secretion patterns between currently depressed and temperamentally at-risk individuals. Further investigation of HPA functioning of individuals at-risk for depression may clarify the stress processes involved in risk for depression onset.