SCHIZOPHRENIA AND MANIC-DEPRESSION - SEPARATE ILLNESSES OR A CONTINUUM

Kraepelin proposed that schizophrenia and manic-depression were distin ct and separable disorders. This hypothesis has been challenged recent ly by proponents of the ''unitary psychosis'' theory which posits a co ntinuum from unipolar to bipolar disorder, continuing through schizoaf fective and schizophrenic illness. In reviewing symptom cluster data a nd family studies, the author suggests that there is no compelling evi dence to indicate a common pathophysiology for schizophrenia and bipol ar disorder. More problematic is a diagnosis of schizoaffective disord er which does not appear to be a stable clinical entity. This would su ggest that schizoaffective disorder is not a true clinical syndrome bu t rather a phenotypic variation.