Polysomnographic and spectral sleep EEG in primary alcoholics: an interaction between alcohol dependence and African-American ethnicity.

BACKGROUND: Disturbances of sleep EEG are prominent in alcoholic patients, persist into recovery, and recently have been found to predict those alcoholics who are most likely to relapse. Increasing evidence indicates that there are ethnic differences in sleep EEG and that African-Americans may be at elevated risk for disordered sleep.
METHODS: This study compared polysomnographic and spectral sleep EEG measures in male primary alcoholic inpatients (n = 31) and age-matched comparison controls (n = 31) stratified by African-American and Euro-American ethnicity.
RESULTS: African-American alcoholic patients showed more severe sleep abnormalities than Euro-American alcoholics, and the interaction between alcohol dependence and ethnicity uniquely contributed to prolonged sleep latency (p < 0.001), loss of delta sleep (p < 0.001), and short rapid eye movement (REM) latency (p < 0.001). Spectral EEG analyses confirmed polysomnographic findings of disordered sleep architecture in alcoholics. Compared with controls, alcoholics had lower delta (0.75-4.5 Hz) activity over the whole night (p < 0.05), reductions in mean spectral power (0.75-40 Hz, p < 0.05), and decreases of delta (p < 0.01) and theta (4.5-7.5 Hz,p = 0.05) activity during the first period of non-REM sleep, with African-American alcoholics having the lowest theta of the four groups.
CONCLUSIONS: In view of the possible connection between relapse and poor sleep and the role of sleep in the maintenance of health, these data have implications for treatment and morbidity outcomes in African-American alcoholics.