The effects of moclobemide on cognition.

The mental ability of the elderly is frequently compromised by age-associated cognitive declines, which may be result of cholinergic deterioration. Depression is accompanied by cognitive performance impairments, and recent work suggests these may be more severe in the elderly. Antidepressants with anticholinergic side-effects, such as the tricyclics, should thus be used with caution in the elderly. A potential advantage of new antidepressants which are relatively free of anticholinergic effects, may be in a reduced liability to impair cognition, whilst maintaining at least equal antidepressant potency. The effects of moclobemide, a novel reversible monoamine oxidase inhibitor, have been studied in both young and elderly volunteers using computerized assessment of a variety of aspects of cognition. In the young the drug was studied within a scopolamine model of the cognitive effects of aging and dementia, while, in the elderly, the cognitive effects of the drug were compared to those of trazodone. In the scopolamine model, moclobemide was significantly superior to placebo and other compounds in antagonizing the cognitive impairments resulting from cholinergic blockade. In the elderly, some improvements were found with moclobemide, particularly in memory, and while an impairment to vigilance was observed, this effect was considerably less marked than with trazodone. Moclobemide would thus appear to have an advantage over antidepressant compounds such as the tricyclics of having a lower liability to impair cognitive efficiency. However, to establish this in depressed patients it will be necessary to incorporate sensitive assessments of cognitive efficiency into trials of the drug in young and elderly populations.