Reduced cerebrospinal HVA concentrations and HVA/5-HIAA ratios in suicide attempters: Monoamine metabolites in 120 suicide attempters and 47 controls

Abstract

Dysfunctions of central monoaminergic systems are important elements of the leading biological hypotheses of suicide and depression. The purpose of the present paper was to study the levels and the relationships between the serotonin metabolite 5-hydroxyindoleacetic acid (5-HIAA), the dopamine metabolite homovanillic acid (HVA) and the norepinephrine metabolite 3-methoxy-4-hydroxyphenylglycol (MHPG) in the cerebrospinal fluid (CSF) in 120 hospitalised suicide attempters and 47 controls (healthy volunteers or patients admitted for minor surgery). The suicide attempters showed significantly lower HVA levels (174±82 vs. 216±96 nmol/L, P=0.004), HVA/5HIAA ratios (1.6±0.5 vs. 2.1±0.6, P=0.0001) and HVA/MHPG ratios (4.2±2.1 vs. 4.8±1.7, P=0.02) than the controls. The correlations between the monoamine metabolites were markedly lower in patients than in controls. CSF 5-HIAA showed no significant differences between patients and controls (107±40 vs. 108±51 nmol/L) or between violent and non-violent attempters (112±58 vs. 105±33 nmol/L). The monoamine metabolites showed no significant differences between survivors and patients who subsequently completed suicide, or between suicide attempters subgrouped by psychiatric diagnoses. The results suggest that low HVA levels and altered relationships between the monoamine metabolites are associated with suicidal behaviour.