In looking at the biological factors involved in suicide, inflammation and inflammatory conditions such as traumatic brain injuries, autoimmune disorders, and neuropsychiatric symptoms are only beginning to be explored.

Familial transmission and history of suicidal behavior and early life adversity (ELA) are distant causes, associated with suicide risk. Substance abuse has been identified as a risk as well.

Mounting evidence shows the immune system as important in the pathophysiology of suicidality. The potential triggers of suicidal behavior include various inflammatory conditions (TBI, vitamin deficiency, autoimmune disorders, and infections), which, through raised levels of inflammation, can cause cause significant problems for individuals. These neurobiological effects might cause profound changes in emotion and behavior, which could ultimately lead to suicide in vulnerable individuals. Many more studies are needed.  

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Role of Inflammation in Suicide: From Mechanisms to Treatment