Pharmaco-EEG test dose response predicts cholinesterase inhibitor treatment outcome in Alzheimer's disease

Previous investigations have indicated that a single dose pharmaco-EEG may predict the outcome of 4-7 weeks of tetrahydroaminoacridine (THA) treatment in dementia of the Alzheimer type (DAT). This open trial study further examined the relationship of quantitive EEG in relation to treatment response by assessing 24 probable DAT patients at baseline, 2 h after their first oral dose (30 mg), and after 12 weeks of THA treatment. Compared to EEG norms, patients, in general, evidenced EEG slowing, as shown by excessive slow (circle minus) and diminished fast (alpha and beta) wave power as well as reduced mean frequencies which were present prior to treatment as well at the end of treatment. The EEG of patients exhibiting stable or improved scores on the Mini-Mental State examination (MMSE) at 12 weeks showed a significantly faster baseline mean alpha frequency as well as a significant reduction in relative circle minus power following the single THA test dose compared to deteriorated patients. A discriminant analysis using test dose response EEG variables correctly classified 75-79% of these two patients groups, suggesting that this procedure may be a useful approach for optimizing patients selection for antidementia treatments. (C) 2000 Prous Science. All rights reserved.