Association of low-voltage alpha EEG with a subtype of alcohol use disorders

Background: Neurophysiological traits may identify more homogeneous subgrou ps of alcoholics. Such discoveries could yield information regarding pathop hysiological development, leading to more specific preventive measures and treatments. In an earlier study of 127 individuals, 59 of whom were unrelat ed, we found that a heritable resting Electroencephalographic (EEG) phenoty pe, i.e., the low-voltage alpha (LVA) trait, was associated with alcohol us e disorders and anxiety disorders. Methods: We evaluated these findings using an independent, similarly establ ished, dataset of 120 subjects. We also extended the study to a larger set of 149 unrelated individuals from a total sample of 247 subjects for whom p sychiatric diagnoses and resting EEG phenotypes were available. Blind-rated psychiatric diagnoses were formulated according to DSM-III-R criteria. Results: In the replication sample, the LVA trait was again more common amo ng subjects with anxiety disorders than among those without. In the total g roup of unrelated individuals, alcoholics were significantly (3 times) more likely to show the LVA trait than were nonalcoholics. Again, individuals w ith anxiety disorders were significantly (3 limes) more likely to exhibit t he LVA trait than were those without anxiety disorders. Of 11 unrelated alc oholics with anxiety disorders, seven showed the LVA trait. It was specific ally the LVA trait and not low amplitude alpha activity that was associated with alcohol use disorders. Conclusions: The results of this replication study and the analysis of the total sample of unrelated individuals support an association between LVA EE G and the subtype of alcohol use disorders associated with anxiety disorder s. The LVA phenotype may be a vulnerability factor for alcohol use disorder s and anxiety disorders.