An inflammatory profile linked to increased suicide risk

Area of Science:

• Neuroscience
• Immunology
• Psychiatry

Background:

• Suicide risk assessment is clinically challenging, necessitating biological markers.
• Suicidal patients exhibit elevated peripheral blood cytokine levels, but the complete inflammatory profile remains unclear.
• The specificity of inflammatory changes to suicidal subjects requires further investigation.

Purpose of the Study:

• To identify distinct immunobiological profiles associated with suicide risk and depression.
• To measure 45 immunobiological factors in peripheral blood to understand these associations.
• To differentiate biological markers specific to suicide risk from those related to depression.

Main Methods:

• Sixty-six women with mood/anxiety disorders were assessed for depression and suicide risk.
• Weighted correlation network analysis explored system-level associations between suicide risk, depression, and plasma immunobiological factors.
• Regression models assessed the impact of confounders like age, BMI, and treatment.

Main Results:

• A distinct biological profile was identified for increased suicide risk, differing from depression.
• Elevated interleukin-6, lymphocytes, monocytes, white blood cell count, and polymorphonuclear leukocyte count significantly impacted suicide risk.
• Interleukin-8 was negatively associated with suicide risk, and results persisted after confounder adjustment.

Conclusions:

• A unique immunobiological profile is associated with increased suicide risk.
• This profile is distinct from that observed in patients with depressive symptoms.
• Findings suggest activated granulocyte-mediated biological mechanisms in individuals at risk for suicide.