A new analysis led by Jasper X.M. Wiebenga, using data from the Netherlands Study of Depression and Anxiety (NESDA), has found that among adults with depressive or anxiety disorders, those who experienced more childhood trauma were more likely to report recent suicidal thoughts and past suicide attempts. The researchers identify multiple psychosocial, personality, lifestyle and biological factors that may mediate this link. The paper, published in the Journal of Affective Disorders, was authored by Wiebenga, Lili Lokhorst, Adriaan W. Hoogendoorn, Henriette D. Heering, Merijn Eikelenboom, Erik J. Giltay, Patricia van Oppen and Brenda W.J.H. Penninx.
One explanation commonly discussed in mental health research is the diathesis-stress model, which posits that childhood trauma creates a lasting vulnerability that can interact with later stresses such as mental illness, difficult life events, or insufficient social support.
The NESDA analysis drew on data collected between 2004 and 2007 from 1,572 individuals aged 18 to 65 who had a depressive or anxiety disorder in the year before joining the study. Participants were recruited from across the Netherlands; 24% had a depressive disorder without an anxiety disorder, 30% had an anxiety disorder without a depressive disorder, and 46% had both. Just over half (55%) reported experiencing childhood trauma, with an average participant age of 41 and 67% identifying as women.
Childhood trauma was measured with the Childhood Trauma Index, which assesses emotional neglect and abuse, physical abuse, and sexual abuse before age 16. Suicidal ideation in the past week was assessed with a shortened version of the Scale for Suicide Ideation, and lifetime suicide attempts were determined by asking participants whether they had ever made a serious attempt to end their life. Participants were divided into three groups: neither recent suicidal thoughts nor a past attempt (1,248 people), recent suicidal thoughts but no past attempt (231), and recent suicidal thoughts with a past attempt (93). Those who had attempted suicide in the past but had no recent thoughts were excluded from the analysis.
Researchers collected data on personality traits, negative life events, social support, loneliness and lifestyle factors, as well as biological markers including C-reactive protein, interleukin-6 and cortisol. They also measured aggression, sleep quality and other factors that could mediate the relationship between childhood trauma and suicidal outcomes.
After adjusting for age and sex, each one-point rise in the childhood trauma score was linked to a 51% increase in the odds of recent suicidal thoughts without a past attempt, and a 2.68-times higher odds of recent suicidal thoughts with a past suicide attempt. Compared with those with no childhood trauma, individuals with severe trauma (a score of four or more) had 2.63 times higher odds of recent suicidal thoughts without an attempt, and nearly ten times higher odds of recent suicidal thoughts with a past attempt.
When testing potential mediators separately, several factors showed significant indirect associations consistent with mediation for both suicide outcomes: aggression, insomnia, lower social support, loneliness, neuroticism, lower extraversion, hopelessness, and a weaker sense of control over life. Higher levels of interleukin-6 also emerged as a potential mediator of the link with suicide attempts, but it accounted for only about 3% of the association and lost significance when other factors were considered together. C-reactive protein and cortisol did not emerge as mediators, and among lifestyle factors, only insomnia played a mediating role; alcohol use, smoking, physical activity and body weight did not.
In combined models that accounted for overlap among mediators, the findings differed by outcome. For recent suicidal thoughts without an attempt, neuroticism, lower extraversion, aggression, hopelessness, insomnia and social support together explained about 66% of the association with childhood trauma. For suicidal thoughts with a past attempt, a weaker sense of control, aggression, insomnia and social support explained about 39% of the association. In both cases, childhood trauma remained significantly linked to the suicide outcomes even after accounting for these mediators.
“Altogether, CT [childhood trauma] was associated with both suicide outcomes, but SI+SA+ in particular. These associations were substantially attenuated in multiple-mediator models in which multiple personality traits, insomnia, and perceived social support showed significant indirect associations consistent with mediation after accounting for shared variance among variables,” the study authors concluded.
“Aggression, insomnia and social support statistically accounted for the link between CT and the outcomes SI+SA- and SI+SA+. Neuroticism, introversion, and hopelessness linked CT to SI+SA- in particular, whilst locus of control showed a significant indirect association consistent with mediation of the association between CT and SI+SA+. The findings point to potentially modifiable factors relevant for suicide prevention, especially aggression, insomnia and social support, that require further investigation in longitudinal studies.”
The researchers emphasised that the study design does not allow causal inferences. Mediators were measured at the same time as suicidal thoughts, so it cannot be determined whether they occurred before or after the suicidal outcomes. Recall bias is possible since childhood trauma was reported in adulthood, though the authors note that retrospective reports can be reliable. The sample was predominantly Dutch and female, which may limit generalisability to men or other cultures.
The authors presented their work as contributing to understanding factors linked to suicide attempts and ideation, with a focus on potentially modifiable targets for prevention. They conclude that further longitudinal studies are needed to confirm these mediating pathways and to explore how they might be leveraged in prevention strategies.
