Evidence for a normal HPA axis response to psychosocial stress in patients remitted from depression

The purpose of this study was to investigate subjective mood and the effect of a psychosocial stress challenge on cortisol response in patients remitted from depression in comparison to healthy controls. Only few studies on small samples have been conducted on the influence of psychosocial stress on HPA system responsivity in this group. Results regarding patients who have achieved clinical remission from depression remain inconclusive so far. In comparison to healthy controls, some studies found blunted cortisol responses to a psychological stressor in patients with remitted depression. However, others found no differences. This discrepancy may be due to use of heterogeneous stress measures or dissimilar sample sizes and characteristics, e.g. including patients with comorbid generalized anxiety or patients with an unknown duration of remission. The present study included 77 healthy controls and 70 unipolar depressed patients who had achieved stable, full remission for at least 6 months (average 31 months) with no further Axis I disorder. Participants underwent the Trier Social Stress Test and salivary cortisol levels and mood were assessed repeatedly during the experimental procedure. For both groups, we observed a marked cortisol response and worsening of mood after the stress challenge. However, no differences between formerly depressed patients and healthy participants were observed. Assuming a disturbed HPA system regulation in acute depression, we interpret these findings as evidence for a restored HPA axis function in fully remitted patients.