Neuroendocrine risk factors of suicidal behavior.

Three of 22 subjects in a study of neuroendocrine correlates of clinical change made serious suicide attempts, 2 of which were lethal. The suicidal subjects had significantly higher 24-hour urinary cortisol levels and significantly lower 24-hour urinary norepinephrine-to-epinephrine ratios than the nonsuicidal patients had. Although the cortisol finding confirms earlier reports, the norepinephrine-to-epinephrine ratio finding is new. The results support the concept that the clinical utility of neuroendocrine measures is enhanced by using a multihormonal profile.