The classical European descriptive psychopathologists in the late-nineteenth and early-twentieth centuries observed that many patients with mood disorders, as well as their relatives, exhibited particular patterns of premorbid personalities that appeared to be attenuated versions of their illnesses. For example, Kraepelin (1921) described four patterns of personality that he considered the “fundamental states” underlying manic-depressive illness: depressive, manic, irritable, and cyclothymic temperament. He believed that these were precursors or “rudimentary forms” of the major mood disorders. Schneider (1958) described similar types; however, he viewed them as personality disorders that were not necessarily related to the mood disorders. Two variants of these types, cyclothymic disorder and dysthymic disorder, are included as mood disorder diagnoses in the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition (DSM-IV; Am. Psychiatr. Assoc. 1994). However, these disorders are defined as fairly severe conditions, with the criteria emphasizing symptomatology rather than personality traits. As a result, these categories appear to be limited to the more severe, symptomatic manifestations of the affective temperaments described by Kraepelin and Schneider (Akiskal 1989).
