Most suicide ideators will never attempt suicide, and most risk factors of suicide are present for both suicide ideators and suicide attempters. The main goal of this thesis is to seek an understanding of how psychological and psychopathological factors can differentiate suicide attempters from suicide ideators. Improving knowledge of factors that are related to the progression of the suicidal process can help assessment and treatment of suicidal individuals and, most importantly, help prevent future suicides.
In study I, a comparison of suicide ideators and suicide attempters was made with respect to self-reported and tested cognitive control functions. Poorer attention control was associated with the suicide attempter group, and a poorer cognitive shift was associated with the suicide ideator group in tested measures of cognitive control. In self-report measures of cognitive control, the analysis showed no difference between the two groups. It is possible that suicide ideators and suicide attempters are not aware of their cognitive strengths and weaknesses.
In study II, analyses were made to study the effect of dissociation on suicide attempts in patients who had experienced sexual abuse. Mediation analysis showed that dissociation mediated a substantive proportion of the relationship between sexual abuse and the number of suicide attempts. Dissociation also mediated the role of sexual abuse as a predictor of having had more than four suicide attempts. It is possible that the depersonalisation effect of dissociation and the habituation of pain from the experience of sexual abuse can contribute to suicide capability.
In study III, a comparison of male and female suicide ideators, low-lethal suicide attempters and high-lethal suicide attempters was conducted to compare the severity of suicidal behaviour, impulsivity, and aggression scores. In a logistic regression analysis, the physical aggression score contributed to the difference between a predicted high-lethal suicide attempt and a predicted low-lethal suicide attempt. A higher score on physical aggression was associated with a high-lethal attempt. Women in the low-lethal suicide attempt group scored higher on impulsive behaviour compared to female ideators. The scores of female high-lethal suicide attempters on hostility were higher than female suicide ideators. Assessment and treatment of suicidal patients should include awareness of the association between high-lethal suicide attempt and higher levels of physical aggression