A MULTICENTER EVALUATION OF NEW TREATMENT EFFICACY INSTRUMENTS FOR ALZHEIMERS-DISEASE CLINICAL-TRIALS - OVERVIEW AND GENERAL RESULTS

Evaluating treatment efficacy in Alzheimer's disease (AD) clinical tri als requires optimal assessment methods to determine the extent and cl inical meaningfulness of potential therapeutic effects of pharmacologi c agents. Development of improved outcome measures for AD clinical tri als is a major objective of the Alzheimer's Disease Cooperative Study (ADCS), an NIA-sponsored, multisite clinical trials consortium. The AD CS Instrument Development Project evaluated the sensitivity, reliabili ty and validity of new or improved measures in each of five assessment domains: (a) cognition (immediate and delayed memory, praxis, attenti on, and executive function); (b) clinical global change; (c) activitie s of daily living; (d) behavioral symptoms (agitation and other noncog nitive symptoms); and (e) cognition in severely impaired patients. A t otal of 306 English-speaking subjects were enrolled in the study, incl uding AD patients stratified by disease severity and cognitively norma l, age-matched elderly subjects. Half were retested at 1 month and 2 m onths after baseline, and all received 6- and 12-month follow-up asses sments. Spanish versions of these new measures are currently being eva luated. The development of this multisite study, the common methods an d procedures, and a detailed description of the cohort are provided in this overview article. This multisite project demonstrates the feasib ility of a consortium approach to instrument development, We were able to develop new instruments and efficiently evaluate their reliability and sensitivity to longitudinal change by capitalizing on the experie nce and patient resources of the participating ADCS research sites.