Low levels of 3-methoxy-4-hydroxyphenylglycol (MHPG) in patients with major depressive disorder (MDD) or bipolar depression were shown to be associated with increased risk of suicide attempts. Hanga Galfalvy, PhD, assistant professor of clinical neurobiology at Columbia University and the New York State Psychiatric Institute, New York, and her colleagues found that patients with the lowest levels of MHPG at baseline were more likely to commit highly lethal suicidal acts.
In this study, 184 drug-free patients with MDD or bipolar disorder underwent lumbar puncture and assays of cerebrospinal fluid (CSF) levels of MHPG. Depressive and suicidal symptoms were also assessed. Of these patients, 101 reported previous suicide attempts. Follow-up interviews were conducted at 3 months and 1 year.
Within the 1-year follow-up, 27 patients attempted suicide, and 2 of these attempts were fatal. Galfalvy reported that in all patients, for each 10 pmol/mL lower CSF MHPG level at baseline, the risk of suicidality increased by 22%. In addition, patients with the lowest levels of MHPG at baseline (mean, 32 pmol/mL) were shown to commit a more lethal suicide actthan patients with higher levels of MHPG at baseline (mean MHPG at baseline, 49 pmol/mL).
Galfalvy concluded that the results of this study indicate the potential for biomarkers to identify patients at risk for highly lethal suicide attempts.