Studies in the Oldest Old: The 90+ Study.
Human Amyloid Imaging Abstract. 2012 Jan 1;
In most of the world, the oldest old comprise the fastest growing segment of the population. As the leading consumers of healthcare and the individuals most affected by dementia, these pioneers of aging present public health challenges and research opportunities to better understand aging and dementia.
The 90+ Study, a population-based sample of more than 1,600 people aged 90 years and older (Laguna Woods, California), comprises one of the largest studies of oldest old in the world. Participants (76% women; mean age 97 years) are followed longitudinally every 6 months with neuropsychological and neurological examinations, medical record review, informant questionnaires and interviews. DNA and brain donation are also requested.
Initial results in this population-based sample show a very high prevalence and incidence of dementia and cognitive impairment in the oldest old. However, typical neuropathological lesions associated with dementia, including amyloid plaques and neurofibrillary tangles (Alzheimer disease), cerebrovascular lesions, and other typical abnormalities associated with dementia, are not necessarily present. Moreover, risk factors associated with dementia and AD in younger old individuals do not appear to be operant in the oldest old. Data from our epidemiological, clinical, radiological, and pathological studies will be presented, and implications for the study of dementia in younger individuals will be discussed.