Functional Tests Help Assess Treatment Efficacy in Dementia

Karl Farcnik, MD, FRCP(C)
Michelle Persyko, PhD

Functional assessments have been a very important component in the development of treatments for dementia, especially Alzheimer's disease (AD). This is due on the one hand to the complexity of the disease process, and on the other to the limited efficacy of current treatments. AD, for example, is associated with symptomatology occurring in three different domains: cognition, activities of daily living (ADL) and behaviour. Cognitive deterioration is of greatest significance in the earlier stages of the disease process. ADL are affected throughout the disease process but are of greatest signifi-cance during the mild to moderate stages of the disease. Behavioural problems, by contrast, tend to be much more significant as the severity of the disease increases. The challenge has been to develop instruments which measure the effectiveness of treatment in all three domains. Initially, the testing focused only on cognition and global functioning based on regulatory requirements. However, as treatment efficacy with drugs such as acetylcholinesterase inhibitors was noted, it became apparent that treatment had an impact on other domains. In fact, many of these instruments have been developed in the past few years.