Cerebrospinal fluid monoamine metabolites and suicidal behavior in depressed patients. A 5-year follow-up study.

We carried out a 5-year follow-up study of suicidal behavior among depressed patients who earlier had determinations of cerebrospinal fluid levels of monoamine metabolites. Patients who reattempted suicide during the follow-up had significantly lower cerebrospinal fluid levels of both the serotonin metabolite 5-hydroxyindoleacetic acid and the dopamine metabolite homovanillic acid. The findings were most striking among melancholic patients. These follow-up results suggest that reduced central turnover of serotonin and dopamine may be associated with further suicidal behavior among depressed patients who have previously attempted suicide.