EEG abnormalities in chronic alcoholism related to age

EEG was studied in 50 chronic alcoholics (age 45 +/- 10 years). All EEGs were classified visually. In addition, a manual analysis from a fronto-central (F3-C3 of F4-C4) lead and a temporo-occipital (T5-O1 or T6-O2) lead was done in 42 cases to obtain the mean frequency of the 6-12 Hz band. The visual classification correlated well with the frequency analysis in the anterior (rs = -0.57, P less than 0.001) and in the posterior (rs = 0.61, P less than 0.001) leads and there was a high positive correlation between the frontal and occipital lead (r = 0.88, P less than 0.001). Half of the records were abnormal. There was a significantly higher proportion of abnormal EEGs in the youngest and oldest patient groups compared with the remainder. EEG-abnormality was significantly related to early start of abuse (before 25 years, P less than 0.05). The findings suggest that alcohol abuse in the teens or early twenties is accompanied by a considerably greater risk of brain damage than alcoholism beginning after 25. However, an alternative explanation, i.e. that the EEG abnormality may represent cerebral dysfunction predisposing to alcoholism is not excluded.