From Isolation to Ideation: The Mediating Effect of Suicidal Intrusions in Loneliness and Suicidal Ideation

Abstract

Introduction Despite extensive research on suicidal ideation, underlying cognitive processes remain underexplored. This study aimed to assess whether suicidal intrusions mediate the relationship between loneliness and suicidal ideation, hypothesizing positive associations among all three variables. Methods A mediation analysis addressed these hypotheses, with a cross-sectional design and a sample of 113 clinical out-patient adults across the Netherlands. Furthermore, a principle component analysis (PCA) identified the key items for measuring suicidal ideation in the Beck Scale for Suicidal Ideation (BSSI) and Suicidal Ideation Attributes Scale (SIDAS). Results No significant indirect effect between loneliness and suicidal ideation when including suicidal intrusions was found (b =.07; 95% CI [-.0455, .01908]). Additionally, loneliness was not significantly associated with suicidal ideation (b = .05, p = .66), or suicidal intrusions (b =.10, p =.26) when including suicidal ideation in the model. However, suicidal intrusions were significantly associated with suicidal ideation when controlling for loneliness (b = .69, p < .001). The PCA identified two main components: one related to cognitions and internal factors, and another to social and external factors. Discussion The study challenges established assumptions about the relationship between loneliness and suicidal ideation while suggesting that suicidal intrusions function as a distinct factor in suicidal ideation. The results underscore the importance of further investigating cognitive processes in understanding suicidal behavior, particularly through longitudinal and more nuanced research.