STAGING METHODS FOR THE ASSESSMENT OF DEMENTIA - PERSPECTIVES

Most dementias in old age are characterized by a progressive course wi th interindividual variability in pattern and rate of progression. Dev eloping a system for staging such dementia poses a challenge in captur ing this variability in a system that will afford comparisons among in dividuals and predictions of future change. Several core questions und erlie the development of such systems: (1) Is there a definable order in which abilities are lost? (2) Which skills and functions should be considered essential for the staging of dementia and what is their rel ative weight? (3) Can the different skills be captured within one stag ing system? (4) How is the whole range of function captured, and are t he differences between stages clearly defined? (5) Which populations c an be rated with each staging system? The determination of this last q uestion is based on understanding which other medical conditions may i nterfere with the course of dementia and how prior characteristics, su ch as education, affect ratings on specific scales for the staging of dementia. Several systems for staging dementia in older adults are des cribed. These include the Clinical Dementia Rating, the Global Deterio ration Scale/Brief Cognitive Rating Scale/Functional Assessment Stagin g System, the Six Clinical Phases of Cognitive Decline, the Hierarchic Dementia Scale, and the Functional Capacity Scale. Some aspects of th e utility of these systems are reviewed, and the issues for further re search are discussed.