HPA Axis Hyperactivity and Attempted Suicide in Young Adult Mood Disorder Inpatients

Background: Hyperactivity of the Hypothalamic-Pituitary-Adrenal (HPA) axis is a consistent finding in Major Depressive Disorder (MDD) and most prospective studies of HPA-axis function have found that non-suppressors in the dexamethasone suppression test (DST) are more likely to commit suicide during follow-up. The results of studies on HPA-axis function and attempted suicide are less consistent. Suicide attempts are more common among young people than the elderly, whereas suicide is more common among the elderly. The impact of age related changes in HPA-axis system activity in relation to suicidal behaviour across the lifecycle may be of importance.

Methods: The aim of the present study was to investigate the DST results in 36 young adult (30 years or younger) inpatients with mood disorder, with (n=18) and without suicide attempt at the index episode.

Results: The DST non-suppressor rate was 25% among young mood disorder inpatients. DST non-suppression was associated with suicide attempt and post-dexamethasone serum cortisol at 11:00 p.m. was significantly higher in suicide attempters compared to non-attempters. The DST non-suppressor rate was 39% in young adult suicide attempters compared with 11% in non-attempters.

Conclusions: The results add to previous evidence in support of the role of HPA axis hyperactivity and suicidal behaviour. The present findings motivate to include HPA axis measures in the assessment of depression in young adults.