Outcome measures for probable vascular dementia and Alzheimers disease with cerebrovascular disease

Vascular dementia (VaD) can be defined as dementia associated with cerebrov ascular disease (CVD), and accounts for a large proportion of all dementia cases. There is substantial overlap in the clinical symptomatology, pathoph ysiology and neurochemical mechanisms in VaD compared with Alzheimer's dise ase, suggesting that an effective treatment for Alzheimer's disease may als o offer benefit as a symptomatic treatment in VaD. However, there are curre ntly no explicit guidelines for conducting clinical pharmacotherapy trials in VaD patients. Two important requirements for assessing therapeutic benef its in such trials are 1) the inclusion of appropriate patients and 2) the use of appropriate outcome measures. Debate on the precise definition of Va D in relation to patient selection criteria continues but many of the recom mendations for outcome measures in Alzheimer's disease are already applicab le to VaD. There is consensus that cognitive and global function measures, and assessments of abilities to perform activities of daily living (ADL) mu st be included as part of the optimal assessment battery in VaD trials. A m easure of reduced behavioural symptoms with associated reductions in demand s on caregivers would also be desirable. However, care must be taken in ext rapolating Alzheimer's disease-specific evaluations to VaD, in that importa nt differences in specific domains affected and characteristics of disease course must be taken into account. Between them, measures such as the Alzhe imer's Disease Assessment Scale-cognitive subscale (ADAS-cog; perhaps with supplemental tests of attention and other frontal lobe functions), evaluati ons of clinical global impression of change and a functional assessment add ressing instrumental as well as basic ADL, e.g. Disability Assessment in De mentia (DAD) scale, should provide a good overall description of VaD-relate d deficits and sufficient appraisal of treatment effects. The Neuropsychiat ric inventory has also been shown to have good potential utility for measur ing behavioural alterations in VaD. These and other assessments are reviewe d to provide a balanced and realistic view of the type of treatment outcome s that can be expected in VaD pharmacotherapy trials, and to address the be st ways of measuring these outcomes.