The assumption that suicide attempts and completed suicides share identical biological pathways may be fundamentally flawed, with profound implications for prevention strategies and clinical risk assessment. This distinction could reshape how mental health professionals identify at-risk individuals and allocate treatment resources.
Analysis of 81,713 suicide attempt cases from comprehensive Danish population registers reveals markedly different genetic and clinical risk profiles between non-fatal attempts and completed suicides. The research employed polygenic scoring across 35 complex traits alongside 28 health conditions, using Bayesian modeling to quantify differences in effect sizes. While both outcomes showed overlapping vulnerabilities in mood disorders and substance use, the genetic architecture underlying each phenomenon demonstrated distinct patterns that challenge unified prevention approaches.
This finding aligns with emerging evidence suggesting suicide attempts and completions may represent separate phenotypes rather than points on a single continuum. Previous research has noted demographic differences between attempters and completers, but this study provides the first large-scale genetic evidence for distinct biological underpinnings. The practical implications are significant: risk prediction models trained on attempt data may poorly identify individuals at highest risk for completion, while intervention strategies effective for preventing attempts may not translate to suicide prevention. The research also highlights limitations in polygenic scoring approaches for complex psychiatric outcomes, where environmental factors and gene-environment interactions likely play substantial roles. For clinicians, these findings suggest the need for differentiated assessment protocols that account for distinct risk trajectories rather than treating all suicidal behaviors as equivalent manifestations of the same underlying vulnerability.