A group of Dutch researchers report that a 115-year-old who remained mentally alert throughout her whole life had a healthy brain that showed no signs of Alzheimer’s Disease or other forms of dementia.
den Dunnen et al had the unique opportunity to evaluate the woman’s performance on psychological tests just a few years before she died, and then later to examine her brain at autopsy.
They say that their findings, which are due to be published in the August issue of the journal Neurobiology of Aging, call into question long-held assumptions about the cognitive decline and neurodegenerative diseases associated with aging.
In 1972, Henrikje van Andel-Schipper, who was then aged 82, gave written consent for her body to be donated to the University of Groningen for the purposes of research and teaching. Nearly 30 years later, she contacted the researchers again, asking if her body would still be useful to them after she had died.
Subsequently, she underwent a series of neuropsychological tests, starting in 2002. When they met her, the researchers found that she had very poor eyesight, but was otherwise “an alert and assertive lady, full of interest in the world around her, including national and international politics and sport.”
Her performance on the tests was initially very good: her scores were above average, compared to healthy adults of 60-75 years of age, on tests for attention, working and semantic memory, verbal reasoning and mental arithmetic.
The woman died on 30th August, 2005, aged 115. At the time, she was the oldest woman in the world. Her body was immediately taken to the dissecting room at the university, and the autopsy began some 2 hours after death.
Examination of her brain showed none of the neuropathological hallmarks of Alzheimer’s – there were no beta-amyloid plaques whatsoever, and only a negligible number of Tau neurofibrillary tangles. These were found mainly in parts of the hippocampus (top, and above left).
Furthermore, the number of cells in a part of the brain called the locus coeruleus was estimated at 16,500 (above right), which is comparable to the number of cells found in healthy people under the age of 60.
It is generally assumed age-related cognitive decline is a normal process that is common to all people, and that Alzheimer’s Disease is an inevitable consequence of aging; the risk of Alzheimer’s increases exponentially past the age of 65, and affects more than 1 in 6 people aged over 80.
Although this is just one case study, it may lead researchers to reconsider some of their assumptions about Alzheimer’s, because it shows that cognitive function can remain unimpaired far beyond the age at which they normally decline, and that Alzheimer’s and other forms of dementia are not necessarily inevitable.
Ironically, the woman weighed little more than 1.5kg at birth, and was not expected to survive for long. On autopsy, a tumour of 7cm in diameter was found in her stomach, but the authors suggest that if she had not died from cancer she could have lived for several more years.
The authors conclude that “this is consistent with the idea that centenarians (people who live longer than 100) do not die from ‘old age’ but from a specific disease.” They argue that genetics probably played a role in the woman’s longevity – her mother died at the age of 100, her maternal grandparents lived to 80 and 85, and her two brothers and sister lived to 72, 82, and 80 respectively.
den Dunnen, W., et al. (2008). No disease in the brain of a 115-year-old woman. Neurobiology of Aging. DOI: 10.1016/j.neurobiolaging.2008.04.010
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