Impact of Microbial Pathogens on Suicidal Behavior: A Systematic Review

Suicide remains a persistent global health challenge, resisting widespread prevention efforts. According to previous findings, toxoplasmosis is particularly associated with altered deci-sion-making, which could lead to risk-taking behavior thereby increasing the likelihood for sui-cidal behavior (SB). In addition, discussion about the role of microbiome in psychiatric disorders has emerged lately, which also makes it relevant to investigate its role in the context of SB. Therefore, the current review aimed to comprehensively summarize existing knowledge regard-ing the association between microbial pathogens and SB. We conducted a systematic search with keywords including suicide and Toxoplasma gondii (Suicid* AND Toxoplasm*) and microbiome (Microbiome AND Suicid*) throughout PubMed to retrieve the related studies up to 09.11.2023. Most results reported significant association between toxoplasmosis and SB, suggesting a higher likelihood of SB in the infected population. Regarding the microbiome, only very few studies in-vestigated an association between SB and alterations in microbiota. Based on those few studies, changes in the microbiome were significantly associated with SB. The cognitive aspects of deci-sion-making in T. gondii infected individuals with SB should be further investigated to unravel underlying mechanisms. Further sufficiently powered studies are needed to establish a link be-tween SB and gut microbiota.