A Link Between the HPA Axis and Suicide?

Question:

"You mentioned a link between the HPA axis and suicide in your Treating the Whole Patient presentation at the 2009 Psych Congress. Please comment further on this."

Jon W. Draud, MD, MS:

Yes, this is an interesting finding and is discussed in detail by Jokinen and Nordström. ¹ Hyperactivity of the hypothalamic-pituitary-adrenal (HPA) axis has long been associated with patients suffering from major depressive disorder, but studies linking HPA hyperactivity and suicide are less numerous and consistent.

Jokinen and Nordstrom evaluated 36 inpatients under the age of 30 with (n=18) and without suicide attempt at the index episode. It has been shown that non-suppressors of the dexamethasone suppression test (DST) are more likely to commit suicide, and the results in this study seem to confirm that. According to the authors, the DST non-suppressor rate was 25%. They found that DST non-suppression was associated with suicide attempt and post-dexamethasone serum cortisol at 11:00 pm was higher in suicide attempters compared to those who did not attempt suicide. Overall, the DST non-suppressor rate was 39% in those who attempted suicide versus 11% in those who did not attempt suicide. These results add to the established body of literature that supports a link between hyperactive HPA and suicide attempts. There were no observed gender differences in the study and this is consistent with previous findings.

As described in a study by Claassen et al., ² depression with a history of suicidal behavior may be a marker for a more virulent form of depression characterized by earlier onset, more overall episodes of depressive illness, and ongoing suicidal ideation. This fits clinically with what I have observed in my practice. One point worth making is that those with early onset and frequently recurrent episodes or inadequate remission rates seem to be at a very high risk of ultimate suicidal behavior.

Clinically, this should serve as a reminder that we must be particularly diligent in assessing and monitoring this subset of patients. It also further reminds us of the critical need to strive for remission as we now know that, neurobiologically, depressive illnesses seem to progress in terms of brain involvement as well as body involvement (i.e., comorbidities). Certainly, this is yet another reminder of the inextricable link between mind and body and how one influences the other.

Finally, these data suggest that it might be wise clinically to include HPA axis measures in the overall assessment of young adults suffering with depression. Depression is a devastating illness to young and older adults, and suicide is the ultimate bad outcome of this debilitating illness. Hopefully, this example of mind-body science has given us further ideas on how to approach depression in our patients.

—Jon W. Draud, MS, MD

Reference

1. Jokinen J, Nordstrom P . HPA axis hyperactivity and attempted suicide in young adult mood disorder inpatients. J Affect Disord . 2009;116(1-2):117-120.
2. Claassen CA, Trivedi MH, Rush AJ, et al . Clinical differences among depressed patients with and without a history of suicide attempts: findings from the STAR*D trial. J Affect Disord . 2007;97(1-3):77-84.