Further analysis of the cognitive effects of tetrahydroaminoacridine (THA) in Alzheimer's disease: assessment of attentional and mnemonic function using CANTAB.

Author(s): Sahakian BJ, Owen AM, Morant NJ, Eagger SA, Boddington S, Crayton L, Crockford HA, Crooks M, Hill K, Levy R

Affiliation(s): Department of Experimental Psychology, University of Cambridge, UK.

Publication date & source: 1993, Psychopharmacology (Berl)., 110(4):395-401.

Publication type: Clinical Trial; Randomized Controlled Trial; Research Support, Non-U.S. Gov't

Results of a placebo controlled cross-over trial (N = 89) of the anticholinesterase drug THA as a treatment for dementia of the Alzheimer's type (DAT) are reported, with reference to previous trials of the drug and the cholinergic hypothesis of aging and dementia. Using computerised tests sensitive to specific aspects of memory and attention, evidence is found for improvements in attentional function rather than memory, in patients with mild to moderate DAT. Although these improvements were significant, they were small and restricted to certain tests of attentional function. Nevertheless, they add to the growing body of evidence that the cholinergic system is involved in the control of attentional processes. The results will be relevant to future investigations into the therapeutic effects of enhancement of the cholinergic system in DAT sufferers.