[Coherence of the electroencephalogram and peripheral markers of nerve tissue damage in depressive disorders]

To evaluate the coherence parameters of the electroencephalogram and the level of peripheral markers of nerve tissue damage in patients with depressive disorders.

Thirty patients with a diagnosis from a cluster of mood disorders: affective disorder within a single depressive episode and recurrent depressive disorder were examined. A control group consisted of 30 healthy individuals, comparable in sex and age to the main group. The bioelectric activity of the brain was recorded and analyzed with the calculation of the averaged coefficients of intra- and interhemispheric coherence. The concentration of calcium-binding protein S100b, the main protein of myelin MBP and glial fibrillar acid protein GFAP was determined in blood sera by solid-phase enzyme immunoassay.

Patients with depressive disorders showed signi cantly lower coefficients of interhemispheric coherence of alpha (p=0.003), beta (p=0.042) and theta rhythms (p=0.041), as well as intrahemispheric coherence of alpha rhythm in the left (p=0.016) and right hemispheres (p=0.026), beta rhythm in the right hemisphere (p=0.034) compared to the control group. Patients with depressive disorders showed a higher concentration of MBP compared to the control group (p=0.008). Additionally, we identified statistically significant correlations between EEG coherence coefficients and serum markers in patients with depressive disorders.

The results clearly confirm the presence of inflammatory changes in the brain in patients with depression, which is reflected in structural and functional changes.