Clinical and Neurophysiological Characteristics of Alcohol Dependence and Its Comorbidity with Affective Disorders

Objective. To identify the characteristics and possible differences in the clinical signs and electroencephalographic parameters in alcohol dependence without and with comorbid affective disorders. Materials and methods. A total of 95 patients with established diagnoses of alcohol dependence took part in the study; of these, 74 had no concomitant affective disorders and 21 had comorbid affective disorders. Histories included the duration of alcohol dependence, the duration of affective disorders, the number of hospital admissions, and the number of suicide attempts. Studies of mental state in patients used a number of psychometric instruments: the Hamilton Anxiety and Depression Rating Scales (HARS, HDRS), the Alcohol Use Disorders Identification Test (AUDIT) scale for the risk of alcohol abuse, and the Clinical General Impression scale (CGI-s). Brain bioelectrical activity was investigated using a 16-channel electroencephalograph. Baseline EEG traces were recorded and absolute spectral power levels and coherence in the α, β, and θ ranges were analyzed. Results and conclusions. Patients with alcohol dependence and comorbid affective disorders were characterized by high risk of suicidal behavior, a higher frequency of hospitalization, and higher levels of anxiety than patients suffering only alcohol dependence. The electrophysiological data showed that patients with these comorbidities, in contrast to patients without them, had higher spectral power in the α rhythm in all areas of the cerebral cortex (except the temporal lobes) and the β rhythm in the occipital cortex, along with increases in interhemisphere coherence in all frequency ranges.