Electrodermal reactivity in male and female depressive patients who later died by suicide.

On the basis of earlier studies on electrodermal responsiveness in patients with suicide attempts, an investigation on electrodermal activity (EDA) in former depressive inpatients was carried out. Male and female depressive inpatients who died of suicide later and participated in an habituation experiment during their inpatient treatment were identified retrospectively and compared (strictly matched by age and sex) to depressive suicide attempters with violent or nonviolent methods, suicide ideators and a nonsuicidal depressive group. In the first part of the study only male depressives (n = 12) who had committed suicide after or during inpatient treatment were compared with their controls. The hypothesis of a expected low electrodermal responsiveness and a fast habituation as an peripheral expression of a central impulse or violence control disturbance could not be confirmed. This was done in the second part of this study. We came to the following results: 1) a tendency to a faster habituation in the violent suicides compared with nonsuicidal depressives and violent suicide attempters plus violent suicide group in male depressives compared to suicide attempters (SA), nonviolent suicide ideators and nonsuicidal depressives. 2) A significant difference with faster habituation rates in a male and female violent suicide group compared with nonsuicidal depressives and again comparing a group of male and female violent suicides and SA with nonviolent SA, suicide ideator and nonsuicidal depressive controls. These results may reflect a dysregulation of violence and impulsivity control mechanism as an underlying disorder or personality trait.