[The role of endogenous and exogenous factors in the development of psychoses in organic dementias in later life].

Influence of different exogenic and endogenic factors (including the very organic process) as analyzed in 231 patients of psychiatric hospital with organic dementia: vascular (VD)--57 cases, senile dementia of Alzheimer's type (SDAT)--29 individuals, dementia conditioned by a combination of vascular and senile-atrophic processes (VD/SDAT)--37 patients, Alzheimer's disease (70 patients) and Pick's disease (38 cases). 160 patients (the study group) had psychotic disorders, 71 patients (the control group) hadn't such disorders. The most frequent (98.2%) and the most various psychotic syndromes (especially delirium and hallucination syndromes) were observed in VD, SDAT and VD/SDAT. A rate of organic process progression was less in patients of the study group as compared with a control one. Prevalence in the study group of cases with endogenic-constitutional predisposition to psychoses development was significant. The role of the other exocerebral factors in origin of psychoses was not so pronounced; among them psychogenias were rather significant, their frequency was 4 times higher in the study group than in the control one. The relationship of psychotic syndromes with origin, stage and progression rate of dementia might indicate a leading role of the organic process in their genesis.