Cyclothymia and labile personality : is all folie circulaire?

Background: Historically, cyclothymia has been used broadly to refer either to a temperament (Kretschmer) or the entire range of bipolar disorders. Within this spectrum, it is uncertain whether it characterizes the hard (or manic-depressive) forms (as Kurt Schneider argued) or its soft expressions (bipolar II and highly recurrent depressions); the latter perspective is in line with Falret's view that the melancholic expressions of his folie circulaire (circular insanity) were highly prevalent in the community. Methods: Eight hundred forty-three outpatients were interviewed with the Schedule for Affective Disorders and Schizophrenia without regard to hierarchical exclusionary rules. Results: Compared to 630 psychiatrically interviewed outpatients who did not have cyclothymia, 163 cyclothymics were significantly more likely to have most of the disorders listed in the SADS in univariate analyses. Discriminant analyses limited the significant associations to labile personality, bipolar II, intermittent depression, secondary depression, hypomanic disorder and schizoaffective mania. Limitation: The RDC construct of cyclothymia is rather broad. Conclusions: Despite such operational breadth, cyclothymia was nonetheless largely limited to the soft end of the bipolar spectrum where labile moods and depressive recurrence predominate. In this sense, it is natural to place it on the border of manic-depressive psychosis. Although Kurt Schneider was the first to describe the labile psychopath [personality], he believed it was unrelated to his narrow concept of cyclothymia, which he used synonymously with manic-depressive psychosis. Our data do not support his position. Instead, they support both Kretchmer's and Falret's views.