A 5-year retrospective examination of cognitive screening test stages in patients with Alzheimer's normal older adults and disease: The Tajiri Project

One conception or aging and cognitive deterioration is that cognitive decli ne becomes common with age, and dementia may be regarded as one extreme of the continuum. An alternative conception is that the cognitive process is s pared by the aging process itself and that cognitive functioning of normal older adults and those with slight cognitive impairment, a CDR (Clinical De mentia Rating) score of 0.5 (suspected dementia), should be different. We e xamined changes in the screening test performances of 170 older adults over a 5-year period and found the following: (a) The CDR 0 (normal) participan ts did not show remarkable changes even in the older groups and (b) the sub items of orientation, memory, and so forth were useful for distinguishing n ormal older adults from early Alzheimer's disease patients. The results sup port the idea that dementia is better conceptualized as an age-related than as an "aging-related" disorder and that a CDR score of 0.5 should be consi dered very mild Alzheimer's disease.