Abstract
The prognostic and therapeutic aspects of catathymic delusional formations, excluding those associated with organic psychoses, are comprehensively presented from five points of view: (1) the present possibilities of psychiatric prognostication; (2) prognostic implications of nosological classifications; (3) prognostic significance of nosographic characteristics; (4) relationship to general rules of psychiatric prognostics; (5) therapeutic points. Under (3) we report our own findings concerning the long-term development of delusional formations and the long-term course of delusional illnesses classified as ‘schizophrenia of late onset’; we report their relationships to the formation of defect syndromes and to the psycho-organic deterioration in old age.