Social Stress and Suicide

Hypothesis: 1. suicide attempters will have a lower cortisol, and, greater alpha-amylase and peripheral inflammatory response after a social stressor, compared to non-attempters 2. suicide attempters will have a hyper-activation of the cardiovascular response during the social stressor and a slower recovery to basal levels, compared with non-attempters. 3\. With respect to decision-making, suicide attempters will demonstrate riskier decision-making than non-attempters after the social stressor, compared to non-attempters. Risk-taking behavior will be related with lower cortisol and higher testosterone levels after the stressor. Measures: electrocardiogram (ECG) and impedance cardiography (IKG) will be used to analyse cardiovascular function during social stressor. Salivary samples to analyze cortisol, testosterone and α-amylase. Blood samples to analyze several peripheral inflammatory proteins. The Iowa Gambling Task a neuropsychologial task to evaluate decision making. Several questionnaires of mood, anxiety and psychological pain during the stressor. And a comprehensive battery of clinical measures for screening and assessment of construct of suicide, and psychiatric and social status. Procedures: Depressed females will be screened and assigned to 2 groups: 1) 40 depressed with suicide attempt history. 2) 40 depressed without suicide attempt history. Participants will confront a virtual version of the Trier Social Stress Test (V-TSST). This test consists in a preparation and execution of a presentation in front of a virtual tribunal for obtain a job position followed by an arithmetic mental task. During the procedure, ECG and IKG will be performed, 5 salivary samples and 5 blood samples (before and after the stressor) and some self-reports of mood, anxiety and pain. After procedure decision making will be assessed. Their participation will consist of 3 visits : inclusion visit (psychiatric interview), visit between 1 to 8 days (social stressor procedure), at 12 months (follow up). Potential impact and next steps: Identifying differences between the two depressed groups in the physiological response to social stress and their subsequent decision making will advance the understanding of the pathophysiological mechanisms of suicide. As social stress is present in several life events during lifetime, know how suicidal people respond to these issues may help in the implementation of preventive interventions.