Nicotine and tetrahydroaminoacradine: Evidence for improved attention in patients with dementia of the Alzheimer type

Abstract

AbstractA placebo‐controlled, single‐blind study investigated the effects of administering three acute doses of nicotine (0.4, 0.6, and 0.8 mg) to a group of patients suffering from dementia of the Alzheimer type (DAT), and to young and aged normal controls. Performance on objective computerised tests provided evidence for improvements in attentional function rather than memory, in patients with mild to moderate DAT. Despite the lack of drug effect on mnemonic ability, these results demonstrate that DAT patients have significant attentional deficits which can be remediated by nicotine administration. They add to the growing body of evidence that the cholinergic system is involved in the control of attentional processes; and are substantiated by the findings of a second study examining the use of a chronic dose of the cholinesterase inhibitor THA, as a treatment for DAT. In this study, effects on both subjective clinical rating scales and objective computerised tests were assessed. In regard to the former, analysis of the three main clinical outcome measures showed statistically significant effects of the drug on the Mini‐Mental State Examination (MMSE) and the Abbreviated Mental Test Score (AMTS), but not on the Activities of Daily Living scale (ADL). Using objective computerised CANTAB tests, sensitive to specific aspects of memory and attention, evidence was found for improvements in attentional function rather than memory, in patients with mild to moderate DAT. These data will clearly provide important comparative data for future investigations of putative cognitive enhancing drugs in DAT sufferers. © 1994 Wiley‐Liss, Inc.