Integrating psychological autopsy and cytokine gene polymorphisms to elucidate suicide risk: an Indian population...

Emerging evidence suggests that neuroinflammation may contribute to suicidal behaviour by altering immune responses and neural-pathways. Polymorphisms in cytokine gene promoter regions have been previously associated with depression and suicidal behaviour. Psychological autopsy is a thorough investigation method to investigate suicide. To date, there is no reported association study linking psychological autopsy outcomes with inflammatory markers. This cross-sectional post-mortem study aimed to investigate the relationship between psychosocial behaviour and inflammatory genetic patterns.

The Comprehensive Psychological Autopsy: Structured Interview Schedule was used to gather psychosocial data of suicide completers (n=234), and genotyping of polymorphic sites in the promoter regions of IL-1β, IL-4, IL-6, IL-10, and TNF-α genes was done.

Our study found a consistent correlation between risk genotypes of all the understudy SNPs with the negative social behaviours. In linear regression analysis, IL-6(-174G/C) demonstrated a protective effect across emotional and negative behavioural traits, whereas TNF-α(-308G/A) was associated with the general behaviour domain.

Although it cannot be generalised at this point, the findings of this study highlight a definite pattern of correlation between genetic-psychosocial and behavioural descriptions of suicide completers, also backed by linear regression models. The findings can be further tested rigorously to confirm worldwide.