Cortisol levels and suicidal behaviour: a meta-analysis

Abstract

Background: Suicide is a major cause of death worldwide, responsible for 1.5% of all mortality. The causes of suicidal behaviour are not fully understood. Dysregulated hypothalamic-pituitary-adrenal (HPA) axis activity, as measured by cortisol levels, is one potential risk factor. This review aimed to estimate the strength and variability of the association between cortisol levels and suicidal behaviour Method: Twenty-four studies met our inclusion criteria (N = 1,862; 765 suicide attempters & 1090 non-attempters). We compared participants identified as having a past history of suicide attempt(s) to those with no such history. Findings: Overall there was no significant effect of suicide group on cortisol (r = .059, p = .242). However, age moderated the association between cortisol and suicide attempts. In studies where the mean age was below 40 years the association was positive (i.e., higher cortisol was associated with suicide attempts) and where the mean age was 40 or above the association was negative. Discussion: These findings confirm that HPA axis activity, as indicated by age-dependent variations in cortisol levels, may play an important role in suicidal behaviour.