Evaluation of changes in functional performance and activities of daily living skills is an essential aspect of the assessment of elderly individuals with chronic illness. Although functional decrement is a central aspect of Alzheimer's disease (AD), many measures currently utilized to assess these changes have limitations. Empirical and systematic examination of the functional changes occurring in patients with AD has resulted in the development of an assessment measure termed Functional Assessment Staging (FAST) that allows for the specific evaluation of these changes throughout the entire course of AD. In this paper the results of three separate investigations regarding the reliability, validity, and progressive ordinality of FAST are described. The results indicate that FAST is a reliable and valid assessment technique for evaluating functional deterioration in AD patients throughout the entire course of the illness. Moreover, the results suggest that the FAST elucidates a characteristic pattern of progressive, ordinal, and functional decline in AD. Because the elements of functional capacity incorporated in FAST are relatively universal and readily ascertainable, as well as characteristic of the course of AD, FAST can serve as a strong diagnostic and differential diagnostic aid for clinicians. The sensitivity of FAST to the entire course of AD, even in its most severe stages, may be indicative of the potential value of this instrument for further investigation of the temporal longitudinal course of AD, and of the relationships between clinical pathology and neuropathology throughout the entire longitudinal course of AD.

Alzheimer's disease (AD) is asociated with an increased mortality in comparison with aged control populations. The relationship between the clinical and the temporal course of AD has not been well studied over significant intervals. Community residing patients with probable AD (N = 103, 42 men, mean age = 70.2 ± 8.0 years) were studied at baseline on demographic and clinical variables, including measures of global deterioration (Global Deterioration Scale; GDS), mental status and cognition (e.g., Mini-Mental State Examination; MMSE), and functional impairment (Functional Assessment Staging; FAST). Baseline characteristics included a GDS range of Stage 4, 5, or 6 (38.8%, 39.8%, and 21.4% respectively) and a mean MMSE score of 15.4 ± 5.6. The mean follow-up interval was 4.6 ± 1.4 year. Follow-ups were done blind to baseline measures and when necessary were conducted in residential and nursing home settings. Of locatable subjects (n = 95, 92%), 30 (31.6%) were deceased. Survivors (n = 65) had a mean GDS stage of 6.2 ± 0.9 and a mean MMSE score of 5.1 ± 6.9; 51% had MMSE scores of 0. Increased age and male gender, but not baseline clinical dementia variables, increased the risk of death (ps < .01). Change in clinical variables correlated significantly with time elapsed (r = .32, p < .05, for MMSE change, to r = .48, p < .001, for GDS change). Significant variance in temporal change (i.e., time elapsed) was accounted for by change in two of the five clinical measures studied (i.e., GDS and FAST; multiple r = .53). The results support previous estimates of mean duration of the GDS and FAST stages. For subjects with probable AD followed over approximately 5 years, clinical variables changed significantly over time in survivors. However, the majority of temporal variance in the course of AD remains unexplained.

Background: Activities of daily living (ADL) deficits are integral components of dementia disorders, and ADL measures are among the most robust markers of the course of Alzheimer's disease (AD). Despite this acknowledged importance, no clearly useful ADL instrument for cross-cultural application in pharmacologic trials in the early stages of AD had been available. Method: An international effort was launched to develop an ADL scale for pharmacologic trials in early AD. Steps taken from 1990 to the present included: (1) international scientific working group meetings and reviews, (2) reviews of existing measures, (3) collating of existent, nonredundant items, (4) querying experts for new items, (5) interviews with informants and subjects in the USA, France, and Germany, toward the identification of potential new items, (6) identification of an item pool based upon these procedures, (7) creation of a trial instrument, (8) piloting of this instrument, and (9) refinement of the scale based upon statistical analysis of the pilot data. Final item selection was based upon: (1) relevance for ≥ 80% of subjects in severity-stratified USA and German samples; (2) absence of gender and national biases; (3) significant (p < .05) discrimination between (a) normal versus mildly impaired and (b) mildly impaired versus moderately to moderately severely impaired subjects; and (4) Global Deterioration Scale (GDS) scores accounting for ≥ 12% of variance in the item after controlling for age and gender. Results: An ADL scale consisting of 40 items that correlate with the global and cognitive progress of AD is developed for international usage in pharmacologic trials in incipient, mild, moderate, and moderately severe AD. The scale contains 40 items falling within 13 ADL categories. The 40-item scale is shown to have .81 correlation with GDS staging,.81 with mental status assessment (Mini-Mental State Examination), and .81 with a psychometric test (the SKT) (p values < .001). Conclusion: This scale can be used to measure therapeutic response in AD.