COGNITIVE DECLINE IN ALZHEIMERS-DISEASE - A LONGITUDINAL INVESTIGATION OF RISK-FACTORS FOR ACCELERATED DECLINE

Background. - Although Alzheimer's disease (AD) is a progressive degen erative condition, there is great intra- and inter-individual variabil ity in rates of cognitive decline. Thus far, little data exist to expl ain such variability. Studies that have attempted to explain it have o ften been based on cross-sectional designs, small sample sizes, and cl inical population data. They have also failed to correct for level of cognitive function, despite clinical evidence that rate of decline var ies among patients with varying levels of cognitive ability. Methods. - This study presents longitudinal data on a community-based sample of 156 patients diagnosed with probable AD, followed annually for one to five years (average age at entry = 79, range 54-91 years). The effect of level of cognitive impairment (as measured by the MMSE and Mattis DRS), demographic characteristics (e.g., education and age), behaviora l problems (e.g., agitation), and co-existent health problems (e.g., v ascular disease) on rate of decline was investigated via multivariate regression analysis. Results. - study results indicate that the averag e rate of decline in cognitive function, as measured by the MMSE and m DRS, becomes more rapid as the disease progresses. Higher education, y ounger age, and agitation at intake were also significantly related to increased rates of cognitive decline.