Vascular dementia: European perspectives.

Vascular dementia (VaD) is the second most frequent cause of organic acquired cognitive dysfunction in the Western world and is probably the first cause in some Asian countries. Therefore, it represents an important target for drug trials in dementia. This report puts in perspective methodological issues in VaD trials, as opposed to Alzheimer disease (AD), and reproduces in extenso the European Medicinal Products Evaluation Agency (EMEA) guidelines for trials of symptomatic treatments of dementia, particularly in AD. There are no explicit guidelines for VaD trials, but many of the recommendations for AD are already applicable to VaD for drugs aiming at alleviating symptoms of dementia. However, VaD can be viewed as being one of the many possible consequences of cerebrovascular diseases, so that there is more to expect from secondary prevention strategies for VaD than for AD (in which both the etiology and the pathophysiological mechanisms are largely unknown). So it seems logical to put more emphasis on the stabilization of the symptoms of VaD, by preventing progression or recurrence insofar as the vascular risk factors for VaD can often be identified and controlled, than in attempting to improve the existing clinical manifestations of established vascular brain damage. Even if purely symptomatic drugs are developed to improve the symptoms of VaD, they will have to be studied in the context of a tight control of existing vascular risk factors. For secondary prevention, trials of at least 1 year seem advisable.