Serum oxytocin concentrations in current and recent suicide survivors are lower than in healthy controls

Suicide and suicide attempts are dramatic events both for the individuals concerned and for their social circles. From a psychopathological perspective, suicidal behavior could be understood as a severe breakdown in relations with their social worlds. Oxytocin is a neuropeptide highly involved in the perception of facets of social relationship such as their quality feelings of belongingness, and mutual trust. Given this, we expected that serum oxytocin concentrations would be lower in current and recent suicide survivors than in healthy controls.

A total of 48 participants (mean age: 27 years; 62.5% females) took part in the study. Of these, 16 (62.5% females) survived a suicide attempt 12-24 h ago; 16 (62.5% females) had made a suicide attempt about 12 weeks ago, and 16 (62.5% females) were healthy age- and gender-matched controls. Blood samples were taken in the morning to assess serum oxytocin concentrations. Participants also completed questionnaires covering sociodemographic information and a scale assessing suicidal ideation.

Compared to healthy controls, suicide survivors had significantly lower serum oxytocin concentrations, but these levels did not differ between current and recent suicide survivors. Compared to healthy controls and recent suicide attempters, current suicide attempters recorded significantly higher scores on the Beck scale for suicidal ideation. Across the sample as a whole, higher scores for suicidal ideation were associated with lower serum oxytocin concentrations. Serum oxytocin concentrations and scores on the Beck scale for suicidal ideation did not differ between females and males.

Given that oxytocin is a neurobiological correlate of subjectively perceived quality of social interaction and social relationships, the results support the notion that suicide attempts are closely linked to suicide survivors' perceptions of the quality of their social lives. Speculatively, and based on the serum oxytocin concentrations, it also appears that 12 weeks after a suicide attempt, the survivor's perceived quality of social life has not significantly improved.