Does Swedish amateur boxing lead to chronic brain damage? 3. A retrospective clinical neurophysiological study

The aim of the present study was to investigate possible chronic brain damage due to Swedish amateur boxing. Forty seven former amateur boxers, 22 with many (HM = high-matched) and 25 with few matches (LM = low-matched) during their career were examined and compared with two control groups of 25 soccer players and 25 track and field athletes in the same age-range. No severe EEG abnormality was found. There was a somewhat higher incidence of slight or moderate EEG deviations among HM-(32%, 7/22) and LM-(36%, 9/25) boxers than among soccer players (20%, 5/25) and track and field athletes (12%, 3/25). Brain electric activity mapping (BEAM), brainstem auditory evoked potential (BAEP) and auditory evoked P 300 potential (P 300) did not differ significantly between the groups. No neurophysiological variable was correlated to the number of bouts, number of lost fights or length of boxing career. Thus, no signs of serious chronic brain damage was found among the amateur boxers or the soccer players and the track and field athletes. However, it cannot be excluded that the EEG differences between the groups may be a sign of slight brain dysfunction in some of the amateur boxers.