Effects of age and parental history of alcoholism on EEG findings in mission Indian children and adolescents

Background: Many, but not all, Native American tribes have some of the high est rates of alcohol abuse and dependence. Yet, risk factors for the develo pment of problem drinking in these high risk groups remain largely unknown. In primarily Euroamerican populations, electrophysiological variables have been associated with risk for alcoholism. The EEG has a specific developme ntal time course that has been described in a diverse set of ethnic groups, but it has not been described in Native American youth, in addition, the r elationship between EEG development and risk for alcoholism in Indian youth has not been previously studied. Methods: Clinical ratings and spectral characteristics of the resting EEG w ere investigated in 140 Native American Mission Indian children and adolesc ents between the ages of 7 and 13 years. The specific aims of the study wer e to (1) investigate the relationship of age and gender with EEG spectral v ariables to determine if this population conforms to similar trends from pr eviously published data in other ethnic groups and (2) to determine whether children with a parental history of alcoholism differ from those without a lcoholic parents on EEG spectral parameters. Results: No excess of abnormal EEG activity was found in this sample of Nat ive American youth. Age, but not gender, was found to have a significant ef fect on EEG spectral characteristics with younger children (7-11 years old) , having significantly more power in slow activity (0.5-7.5 Hz) and in alph a power (8-12 Hz) as well as slower alpha frequencies than older children ( 12-13 years old). Consistent with other studies: of Native American youth, 66% of the children and adolescents participating in this study had at leas t one parent who had a lifetime diagnosis of alcohol dependence. However, a n ANCOVA that covaried fur age and gender revealed no significant differenc es in power or frequency characteristics of the EEG on the basis of parenta l history of alcoholism. Conclusions: These studies suggest that this sample of Mission Indian child ren, despite high levels of parental alcohol dependence and low socioeconom ic status, show normal EEG development. As yet, no relationship has been fo und between any specific EEG phenotype and parental history of alcoholism i n this population, however, further EEG maturation may be necessary before any relationships can be fully delineated.