Cortisol Reactivity Elicited by Psychosocial Stress Paradigms and Suicidality: A Systematic Review and Meta-Analysis
Creators: name: Besney, Richard Mark Anthony
Publisher: name: Werklund School of Education
Year: 2023
Subjects: subject: Suicide
subject: biomarker
subject: cortisol
subject: hypothalamic pituitary adrenal axis
subject: Educational Psychology
subject: Psychology--Clinical
subject: Psychobiology

description: Background: Suicide is a leading cause of worldwide death. While our knowledge related to risk factors of suicide has grown over recent decades, our ability to predict and prevent suicide has not improved. The identification of valid and reliable biomarkers of suicidality would supplement existing screening measures by incorporating objective indicators of risk. A growing body of literature has identified altered functioning of the hypothalamic-pituitary-adrenal (HPA) axis as one potential biomarker for suicide, which can be measured using psychosocial stress paradigms to elicit cortisol reactivity. However, findings from existing literature are discrepant in terms of the directionality of cortisol reactivity, or whether hyper- or hypo-responsiveness is associated with suicidality. This thesis systematically reviewed existing studies related to cortisol reactivity and psychosocial stress paradigms, and also conducted meta-analyses to synthesize main findings of cortisol reactivity. Methods: Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines were used for the literature search. Information related to participant characteristics, methodology, and main findings were extracted from included studies. Cortisol reactivity findings were analyzed in terms of AUCi. Estimation of standardized mean differences was carried out on suicide attempters versus non-attempters, and suicidal ideators versus non-ideators. Moderation analyses were then conducted to determine if results varied as a function of age and sex. Results: Nine studies were included for review based on eligibility criteria. Mental health characteristics of participants were variable. Impulsivity/aggression, duration of suicidal ideation, recency of suicide attempt, family history of suicide attempt, and past behavioural problems impacted the association between cortisol reactivity and suicidality in the included studies. Due to availability of data/information, only six of the nine studies were included for meta-analysis. No overall group differences in cortisol reactivity between suicide attempters versus non-attempters (Cohen’s d = -0.09, 95% CI = -0.36, 0.19, p = 0.53), nor suicide ideators versus non-ideators (Cohen’s d = 0.13, 95% CI = -0.13, 0.39, p = 0.32) were found. Age and sex did not moderate analyses. Conclusion: Findings on the association between cortisol reactivity using psychosocial stress paradigms and suicidality are discrepant. Such findings may be complicated by numerous participant factors and differences in methodology across studies. Given a small number of existing studies, generalizations about the utility of cortisol reactivity as a biomarker of suicidality and associated risk cannot be made, however. The focus of future literature should include other potential biomarkers from the HPA axis, other biological systems, as well as machine learning approaches to enable integration of multiple risk factors.