Congratulations for the article about "Karl Leonhard's re-evaluation of Kraepelin's diagnostic concept of manic-depressive psychosis".

I would like to reference an important family study of Phuhlmann et al. (2004) to the discussion. Based on modern and highly sophisticated methodology, the authors investigated the relations of cycloid psychosis to bipolar affective disorders. The authors personally examined all living and traceable adult first-degree relatives of 45 cycloid psychotic, 32 manic-depressive and 27 control probands blind to the diagnosis of the index proband. A catamnestic diagnosis was established for each of 431 relatives blind to family data. Age-corrected morbidity risks were calculated using the life-table method. The results were striking. Relatives of cycloid psychotic patients showed a significantly lower morbidity risk for endogenous psychoses in general and manic-depressive illness compared to relatives of patients with manic-depressive illness. The familial morbidity risk for cycloid psychoses was low and did not differ significantly in both proband groups. Further, relatives of cycloid psychotic patients did not differ from relatives of controls regarding familial morbidity. This study indicates that cycloid psychoses can hardly be integrated in the highly genetically loaded bipolar affective spectrum. The obvious fact that cycloid psychoses in almost all cases are triggered by endogenous or exogenous stress factors like giving birth to a child, by psychosocial stress during work or in relationships, by cocaine or other stimulant drug use (Franzek en Musalek 2011) seems to justify the term "stress induced psychoses". It is suggested that a genetically vulnerable stress (related) system may be a major etiologically factor in cycloid psychosis that is different form the genetically based bipolar affective disorders.

References:

Phuhlmann B, Jabs B, Althaus G, Schmidtke A, Bartsch A, Stöber G, Beckmann H, Franzek E. Cycloid psychoses are not a part of a bipolar affective spectrum. Results of a controlled family study. Journal of Affective Disorders  2004; 83:11-19.

Franzek E, Musalek M.Advances in psychopathology, classification and diagnosis of psychosis and its clinical implications. Minerva Psichiatrica  2011; 52:171-185.

Ernst Franzek

February 18, 2016