Changes in background electroencephalographic activity in patients with epilepsy and/without comorbid depression

Abstract

PURPOSE: Depressive disorders are the most common interictal psychiatric comorbidity in epilepsy. Recent data highlights the possibility of a close bi-directional pathophysiological relationship between these two disorders. Early detection and treatment of interictal depressive disorder (DD) may significantly improve patients' quality of life. The aim of the present study was to compare recorded interictal electroencephalographic (EEG) data in patients with epilepsy with and without comorbid DD. MATERIAL AND METHODS: Forty patients with epilepsy were divided into two groups according to the presence/absence of comorbid DD. They were diagnosed by applying the International Classification of Diseases, Version 10 (ICD-10) diagnostic criteria. Evaluation on Hamilton Depression Rating Scale (HAM-D-17) supported the diagnosis. Nineteen-electrode electroencephalography (EEG) with spectral analysis of the power was recorded for each participant. Gender- and age-matched subjects comprised a control group. RESULTS: An increase in slow wave EEG activity in the frontal and temporal lobe as well as a decrease in sensory motor rhythm was found out in the group of patients with epilepsy and comorbid DD. No such findings were detected in the group of patients with epilepsy only. CONCLUSION: Atypical presentation of interictal DD is common in epilepsy. Comorbid depression remains unrecognized and untreated in a great proportion of patients. Detection of certain patterns of EEG changes may be useful as a screening tool for forwarding these patients to a further psychiatric evaluation. It can serve as a basis for applying alternative therapeutic methods such as the biofeedback method. Scripta Scientifica Medica 2013; 45(1): 48-51.