CSF 5-HIAA predicts suicide risk after attempted suicide.

Suicide risk after attempted suicide, as predicted by cerebrospinal fluid (CSF) monoamine metabolite concentrations, was studied in a sample of 92 psychiatric mood disorder inpatients admitted shortly after attempting suicide. The potential of the serotonin metabolite 5-hydroxyindoleacetic acid (5-HIAA) in the CSF to predict suicide risk within the first year after attempted suicide was studied by means of survival analysis after after median split subgrouping. Eleven patients (12%) committed suicide within 1 year after attempted suicide. Eight of these belonged to the below-the-median (< 87 nM) CSF 5-HIAA subgroup, that is, the suicide risk was 17% as compared with 7% among those with above-the-median CSF 5-HIAA. The cumulative number of survived patient-months during the first year after attempted suicide was significantly lower in the low CSF 5-HIAA subgroup. It was concluded that low CSF 5-HIAA predicts short-range suicide risk after attempted suicide in mood disorder psychiatric inpatients. These findings lend further support to the serotonin hypothesis of suicide risk.