The Marke-Nyman Temperament (MNT) Scale in suicide attempters

A total of 89 suicide attempters were diagnosed according to the DSM-III-R, and categorized according to suicide method as ‘violent’ and ‘non-violent’ attempters, and also as those who had made previous suicide attempts (‘repeaters’) and those who had not (‘non-repeaters’). All of the subjects completed the MNT questionnaire. Our hypothesis was that the temperament patterns would reflect specific clinical characteristics, such as psychiatric diagnoses and type of suicidal behaviour. The ‘validity’ (ranging from fatiguableness to a high level of psychic energy) showed a bimodal distribution, suggesting the existence of two subgroups. The subjects with adjustment disorders displayed a significantly higher mean validity than the other patients. The lowest validity scores were found in subjects with bipolar depression. Men showed significantly higher 'stability’ (reflecting emotional distance from others) than women. Subjects with major depression and those who were ‘violent’ suicide attempters showed somewhat higher 'solidity’ (unchangeability, non-impulsiveness) compared with the other groups. Female ‘non-repeaters’ displayed significantly lower solidity than males or other females. In general, no clear temperament patterns were detected in patients categorized according to type of suicidal behaviour. In contrast to the findings of studies of normal populations, the intercorrelations between the dimensions were considerable, especially among the men. This prompted us to perform a cluster analysis procedure in which the subjects were allocated to five clusters according to the MNT dimensions. No distinct clinical characteristics appeared in these clusters, except in the cluster with the highest validity and the lowest stability, as 54% (P= 0.014) of the patients in this cluster had an adjustment disorder diagnosis. These temperament results reflect the clinical heterogeneity of patients who attempt suicide.