Measuring the effects of anti-dementia drugs in patients with Alzheimer's disease

A large number of experimental compounds are being developed for the treatment of patients with Alzheimer's disease (AD). As different compounds may have different effects on CNS function, depending on which neurotransmitters they affect, adequate profiling will require the use of several tests. The difficulties facing the psychopharmacologist in a clinical trial setting of dementia are numerous. Many of the current measures, particularly ratings scales, measure a complex range of variables in the same instrument and this makes interpretation of results difficult. More objective measures are needed but these are often chosen without regard to what the instrument measures in terms of psychological function. Despite these difficulties the need to evaluate anti-dementia drugs will become increasingly important now that specific drugs for the treatment of AD have become available. It is likely that the best strategy for evaluating such compounds will be via a test battery, comprising a range of instruments (psychometric, clinical and neuropsychological) each measuring a clearly defined aspect of cognitive function. It may be time to rethink the evaluation of anti-dementia drugs from a psychopharmacological perspective and, in particular, to develop more objective and quantitative measures to be used alongside more ‘traditional’ instruments.