The influence of inflammatory cytokines in physiopathology of suicidal behavior

Risk of self-harm and nonfatal suicide attempts, and completed suicide in patients with psoriasis: a population-based cohort study

“…In our study, we did not find any increased risk of completed suicide in patients with psoriasis, but the risk of suicide in patients with AD was significantly increased. In potential support of the latter finding, significantly increased levels of IL‐4 and IL‐13 were found in post mortem brains of suicide victims . Indeed, IL‐4 and IL‐13 are pleiotropic Th2 cytokines produced by a wide variety of different cell types that are involved in the pathogenesis of AD, although their exact functions in depression and suicidal behaviour are still unclear …”

“…Indeed, studies have shown strong associations between IL‐17A and depression, suggesting potential beneficial effects of IL‐17A inhibition in depressive disorders . Similarly, a role of inflammation in suicide and suicidal ideation has been proposed . In fact, studies have found increased levels of proinflammatory cytokines such as IL‐6 and TNF‐α in suicide and suicide attempt subjects, and it is tempting to speculate that treatment with TNF inhibitors may favourably affect suicidal behaviour .…”

“…Similarly, a role of inflammation in suicide and suicidal ideation has been proposed . In fact, studies have found increased levels of proinflammatory cytokines such as IL‐6 and TNF‐α in suicide and suicide attempt subjects, and it is tempting to speculate that treatment with TNF inhibitors may favourably affect suicidal behaviour . Along this line, IL‐6 is elevated in the cerebrospinal fluid of suicide attempt subjects, and peripheral blood levels of IL‐6 have been put forward as a potential biological suicide marker …”

“…Interestingly, research in neuroinflammation associated with diseases of the central nervous system, including depression, has in recent years increasingly also focused on the role of the same proinflammatory cytokines that are involved in psoriasis and AD . Levels of several Th1 and Th2 cytokines such as IL‐1, IL‐4, IL‐6 and TNF‐α have been shown to be increased in cerebrospinal fluid and post mortem brains of suicide victims, and may affect suicidal behaviour …”

Suicide and Lyme and associated diseases

“…Infections impact CNS functioning by provoking cytokines that “can modulate the concentration of monoaminergic neurotransmitters and their metabolites in various regions of the CNS” 77. There is a significant body of research demonstrating a strong association between inflammation, brain inflammation, elevated cytokine levels, and suicide 78–80. “Most suicide attempters, or subjects with suicidal ideation, show an imbalance in the immune system.”81 Interferon treatment for hepatitis C has been a clinical model demonstrating the significance of inflammation-mediated mental symptoms including suicide 82.…”