Blood and Brain Tissue Biomarkers for Autoimmunity and Inflammation in Suicidal Behavior and Suicidal Ideation
DOI:
https://doi.org/10.12974/2313-1047.2025.12.07Keywords:
Psychiatry, Suicidal behavior, Autoantibodies, InflammationAbstract
Suicidal behavior and ideation are serious psychiatric symptoms that must be taken seriously and that can trigger a genuine suicide if there is no timely intervention. Biomarkers that can predict such behavior are therefore incredibly important in this context. This article discusses inflammatory markers that may be elevated in patients presenting suicidal behavior. There is evidence that autoantibodies against thyroid tissue are associated with suicidal ideation and behavior. However, there are also autoantibodies against neuronal and glial antigens, that according to recent studies play an only minor role in suicidal behavior. We can therefore assume that overall, autoimmune processes in the thyroid gland play a role in suicidal behavior and suicidal ideation in association with brain function and inflammatory processes. The relationship between neural autoantibodies and suicidal behavior remains under investigated, but the first studies have indicated that suicidal behavior affects only a small minority of patients with neural autoantibodies, if any. Suicidal behavior rarely occurs as a clinical feature in autoimmune encephalitis with autoantibodies. Taken together, the studies show that in a minority of patients with suicidal behavior, pro-inflammatory markers are more prevalent than anti-inflammatory markers.
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