EEG Parameters of Treatment Response Prediction in Manic–Delusional and Manic–Paraphrenic States

The study of clinical, psychopathological and neurobiological characteristics of affective-delusional states is important for clarifying the diagnosis and individual prognosis of disease development. Quantitative EEG allows us to assess objectively the brain functional state of such patients and to clarify the neurophysiological mechanisms underlying the characteristics of syndrome structure of mental disorders. The aim of the study was to search for baseline amplitude–frequency and spatial characteristics of EEG as possible indicators for prediction of therapeutic response in patients with manic–paraphrenic and manic–delusional states in the framework of endogenous mental disorders with different syndrome structure. The study was conducted in 73 women aged 18–55 years with affective–delusional disorders meeting the criteria of diagnosis codes F25.0 and F25.2 according to ICD-10 and differing in the syndrome structure: with a predominance of sensual-delusional (28 patients) or ideational–delusional (31 patients) disorders, as well as a group with manic–delusional states (14 patients). The quantitative assessment of patient’s mental state in the dynamics of therapy was carried out by the YMRS and PANSS clinical scales. The brain functional state was assessed using multichannel recording and spectral analysis of resting EEG. The correlation analysis revealed the relationships between individual quantitative clinical estimates after a course of therapy and EEG parameters recorded prior to therapy (potential predictors of therapeutic response). The intergroup peculiarities of the structure of correlations between the baseline (recorded before the therapy) individual EEG spectral power values and the quantitative YMRS and PANSS clinical estimates after the therapy were revealed in three syndromally different groups of patients. These EEG parameters can be considered as candidates for the role of predictors of individual therapeutic response in patients with manic–delusional and manic–paraphrenic states. They reflect either the initially reduced brain functional state, in particular, the frontotemporal cortical areas, or its initial hyperactivation, i.e., disturbance of the normal ratio of excitation and inhibition processes. Thus, variations in the ratio of excitation and inhibition processes, reflected in the baseline resting EEG parameters, apparently determine both the clinical manifestations of manic–paraphrenic and manic–delusional conditions and the brain adaptive resources in terms of the capacity and magnitude of patient’s individual therapeutic response.