In late life patients considerably more seldom than patients of other age groups reach attention of psychiatrists due to obliteration of symptoms of mental suffering, their masked by somatic symptoms manifestation, not seldom - negative attitude of relatives toward psychiatric assistance etc.

Study of patients of elder and older age at units of somatic hospital of another profile (therapeutic, cardiologic, neurological, traumatologic) has shown that mental disturbances are revealed in 74,4 % of them. Non-psychotic forms of disorders are basic (73,8 %), more seldom psychoses are found (18,6 %) and dementias of various nature (7,6 %). Of most prevalence in this contingent were disorders related with cerebral-vascular diseases (42,6 %), including those with acute disturbances of brain blood circulation (20,5 %). Somatogenic mental disorders occupy more modest place counting 8,8%. Neuroses including nosogenias are observed in 9,2 % of cases. Endogenous diseases are rarely found in patients of a somatic institution (6,7 %).

In recent years significant growth of organic mental disorders in Russian Federation occurs predominantly at the expense of the elderly. In structure of this pathology as selective epidemiological investigations show the first place according to incidence rate is occupied by cerebral-vascular diseases (34,1 %); the second place is occupied by neurotic disturbances (26,0 %); the third one - affective disorders (15,4 %).

Differences in sickness rate and morbidity in such conditions identified by researchers in different populations may reflect more particularly their diagnostic approaches than the true differences in incidence and prevalence.