Oleychik, M.I.

Background. The study of cognitive functions in patients at high risk for psychosis is an urgent task for solving the problems of preventive intervention and early diagnosis of severe psychotic states. Previous studies describe the occurrence of cognitive impairment in patients long before the manifestation of psychosis, which suggests the high value of diagnosing cognitive functions at the early stages of mental illness.

Objective. The goal is to identify the peculiarities of cognitive functioning of patients with depression at high risk for psychosis in comparison with patients with non-psychotic depression and depressive state after the first psychotic episode.

Study Participants. The study involved 115 female patients: 44 patients with depression without psychotic symptoms (NPD); 46 patients with depression at clinical high risk for psychosis (CHR); and 25 patients depressed after a first episode psychosis (FEP).

Methods. Cognitive functions were assessed using the Brief Assessment of Cognition in Schizophrenia (BACS), the Similarities subtest and the Picture Completion subtest of the Wechsler test, and the Interpretation of Proverbs task. The level of formation of motivation for examination was assessed with the interaction rating scales of the Wisconsin Card Sorting Test.

Results. Various cognitive impairments in the CHR group in their severity can be similar either to the NPD or FEP group or occupy an intermediate position in severity between the other two groups. The motivation for examination is harder to form in the CHR group than in other groups, though it retains its connection with cognitive functions, unlike post-psychotic states.

Conclusions. Cognitive impairments in depression with a clinical high risk of psychosis are heterogeneous and do not clearly correspond to the cognitive profiles of affective or psychotic disorders. Specific cognitive impairments in depression with clinical high risk for psychosis are independent of the expressedness of positive symptoms or deficit of motivation in cognitive activity.