was also found after fenfluramine challenge, but the effects were not as statistically robust as those with cortisol.

The stress response also affects the structure and function of noradrenergic pathways. Fewer noradrenergic neurons in a nucleus found in the brain stem, the locus coeruleous, have been found postmortem in studies of depressed patients who completed suicide (Pandey and Dwivedi, 2007). The noradrenergic system is also a target of antidepressant treatments. Adults reporting past child abuse have excessive norepinephrine release after a laboratory stress test (Heim and Nemeroff, 2001). A noradrenaline metabolite in the cerebral spinal fluid predicts the lethality of a suicide attempt (Galfalvy et al., 2009). One key hypothesis, observed Mann, is whether excessive norepinephrine release related to the long-standing stress of severe major depression in those with childhood adversity or in genetically predisposed people eventually leads to hopelessness and pessimism. Those psychological traits, in turn, place these people at higher risk for suicidal behavior.

In summary, Mann believes that biological markers such as low serotonin levels predict future completed suicide. Biological findings, along with other psychological and social risk factors, may eventually be used in an integrative way to shed light on the emergence of suicidality in childhood, adolescence, and adulthood (Box 2-1).

BOX 2-1

Summary of Research Findings Reported by Presenters in This Session

  • Epidemiological and clinical trial findings reveal that suicide ideation is not a strong predictor of a suicide attempt.

  • New approaches show promise for strengthening the relationship between ideation and suicidality if more nuanced information about the nature of ideation is collected simultaneously.

  • One approach seeks real-time electronic monitoring that prompts patients to report more about ideation at the time of its occurrence.

  • Another approach shows that measuring “suicidal ideation at its worst point in time,” through a questionnaire, is a significant predictor of suicide completion (Beck et al., 1999).

  • Biological measures in response to serotonergic challenge also show promise if integrated with psychological and social measures. In a prospective study, blunting of cortisol response and the worsening of mood, plus younger age, predicted subsequent suicide attempts in depressed patients with a previous attempt (Keilp et al., 2008).

The National Academies | 500 Fifth St. N.W. | Washington, D.C. 20001
Copyright © National Academy of Sciences. All rights reserved.
Terms of Use and Privacy Statement