Personality traits of Japanese patients in remission from an episode of primary unipolar depression

Personality traits were assessed by means of the Munich Personality Test (MPT) in 75 Japanese subjects, 27 patients in remission from an episode of moderate to severe primary unipolar depression, with melancholic features during one episode or more of the disorder, in 24 patients in remission from other non-organic mental disorders and in 24 healthy controls. Compared with healthy controls, unipolar depressives displayed decreased Frustration Tolerance and elevated Rigidity as well as a stronger Orientation towards Social Norms. No significant difference was found between patients in remission from either unipolar depression or other mental disorders. However, the increase in Rigidity in comparison with healthy subjects was significant in the depressives only whereas the other patients, in contrast to the depressives, had significantly lower scores in Extraversion than the healthy subjects. Our results in Japanese patients are similar to findings of previous German studies, including two high risk studies, in which the same assessment instrument was used. This suggests that, beyond cultural differences, Rigidity, possibly in combination with a strong Orientation towards Social Norms and a reduced Frustration Tolerance, is a stable vulnerability marker for at least the more severe forms of primary unipolar depression.