The ability to recognize odors in patients suffering from the schizophrenia spectrum disorders and depressive disorders

Abstract

The works purpose was to study connection between smell malfunction that reduces level of smell recognition (anosmia) and current emotional condition of patients who suffer from schizophrenia spectrum disorders and patients with depressive disorders.
 Methods of research. Patients who suffer from schizophrenia spectrum disorders (F20, F21, F23, F25), depressive disorders (F32, F33), and healthy individuals were examined. Methods of evaluation of current emotional condition were Beck Depression Inventory and SnaithHamilton Pleasure Scale. To determine malfunction of smell function Professional olfactometric set of odorous substances RAMORA was used.
 Results. In patients with schizophrenia spectrum disorders, the level of smell recognition is significantly lower than in the group of patients suffering from depressive disorders and the group of healthy people. When comparing patients with depressive disorders with a group of healthy individuals, there is a slight decrease in the identification of odors, close to normal values. In patients with depressive disorders and patients with schizophrenia, an increase in the level of anhedonia and depression is detected in comparison with healthy subjects. The overall level of smell recognition is not related to the indicators of the current emotional state (depression and anhedonia) in both clinical groups. However, the relationships between the identification of individual odorants and the actual emotional state in the group of patients with schizophrenia spectrum disorders were revealed.
 Conclusions. A decrease in the level of odor identification (anosmia) is observed in patients with schizophrenia spectrum. These disorders are not typical for patients with depressive disorders and people who do not suffer from mental illness. The obtained results require additional research. It can be assumed that the indicators of olfactory processes can be an additional diagnostic method of the emotional and personal sphere of patients with the schizophrenia spectrum disorders.