Temperamental diagnostics and biochemistry in suicide attempters

Sammanfattning: The aim of the present thesis was to study temperament traits and their relationships to psychiatric diagnoses, suicidal behavior and a number of biological measures in a sample of hospitalized suicide attempters. The subjects showed a bimodal distribution on the Validity scale from the Marke-Nyman Temperament (MNT) inventory, with a large subgroup showing low Validity. Cluster analyses of the scores on the Karolinska Scales of Personality (KSP) were carried out in order to categorize the subjects according to temperament traits. One group, many of which had major depression, showed a "neurotic and introverted" profile, with high anxiety and low extraversion scores. One group with high impulsiveness, anxiety and psychoticism often had dysthymia and a personality disorder diagnosis. Two groups, which on the whole had normal scores on all scales, often had adjustment disorders. The Hopelessness scale, The Suicide Assessment Scale and the levels of cortisol after suppression of dexamethasone were significantly different in the temperamental clusters. The levels of monoamine metabolites in the cerebrospinal fluid (CSF) did not show any significant differences between the temperament clusters, and the associations with repeated suicide attempts did not reach significance. Urinary cortisol was positively associated with Stability from the MNT inventory. In alcoholic suicide attempters, the levels of the serotonin metabolite 5-hydroxyindole acetic acid (5-HIAA), homovanillic acid (HVA), urinary cortisol and the activity of monoamine oxidase (MAO) in platelets were positively associated with Solidity (reflecting impulsiveness). In the whole sample of suicide attempters, no consistent relationship between low solidity and low CSF 5-HIAA or low MAO activity was found. In contrast to a previous hypothesis, there was no significant relationship between low total serum cholesterol levels and low levels of 5-HIAA. There were, however, positive relationships between high density lipoprotein cholesterol (HDL) and CSF HVA (r=0.39, p=0.04) and CSF 5-HIAA (r=0.034, p=0.07). The results emphasize the biological and temperamental heterogeneity amongst patients who have attempted suicide.