Reversibility of brain-stem evoked potential abnormalities in abstinent chronic alcoholics: one year follow-up.

Brain-stem auditory evoked potentials (BAEPs) were studied in 34 chronic alcoholics who had been abstinent for 1 year, and in age- and sex-matched control subjects. The patients were examined 3 times, at 1 month, 5 months and 1 year after the start of the abstinence treatment. At 1 month of abstinence the alcoholics showed differences with respect to controls in the peak V latency (P < 0.01), and in the III-V (P < 0.01) and I-V (P < 0.01) intervals. After 1 year of abstinence a significant improvement in the V (P < 0.01), III-V (P < 0.01) and I-V (P < 0.01) parameters was recorded. The most notable development was in the 5-12 month period, with shortening i latency (P < 0.01) and in the I-V interval (P < 0.01); in the first 5 months there was only shortening in the III-V interval (P < 0.01). This improvement was also indicated by a decrease in the number of patients with BAEP parameter abnormalities. The recovery of the functions impaired by chronic alcohol consumption after 1 year of abstinence was incomplete, although the tendency was towards normalization.