The 90 + study. Research findings about the oldest old.

This is one of the largest studies done on the oldest old in the world. Started in 2003 in the US, more than 1,400 people have enrolled so far. It asks an important question in our ageing population ‘What allows people to live to age 90 and beyond?’ Some of the findings are surprising.

Method

Participants are visited every six months by neuropsychological testers and neurological examiners. Researches at the Clinic for Aging Research Education (CARE) in Laguna Woods collect information about diet, activities, medical history, medications and other factors. The participants are also given cognitive and physical tests to judge function.

Major Findings

Many scientific papers have been published, but these are some of the main findings:

• People who drank moderate amounts of alcohol or coffee lived longer than those who abstained.
• People who were overweight in their 70’s lived longer than normal or underweight people did.
• Over 40% of people aged over 90 and older suffer from dementia while almost 80% are disabled. Both are more common in women than men.
• About half of people with dementia (i.e. 20%) over age 90 do not have sufficient neuropathology (physical damage) in their brain to explain their cognitive loss.
• People aged 90 and older with an APOE2 gene are less likely to have clinical Alzheimer’s dementia, but are much more likely to have Alzheimer’s neuropathology in their brains. (More likely to have physical damage but less likely to have measurable symptoms).

What does this mean? – my thoughts on the findings

The good news is that some of the things that we previously associated with decline and dementia (alcohol, coffee and weight) are not a problem. This is a correlation and not a cause therefore it doesn’t indicate that drinking more alcohol or gaining more weight enables extra longevity!

The news about dementia is interesting – I think that it is possible the 20% with no physical damage are demented only because they have stopped using their brains as they got older (use it or lose it) and therefore need not have dementia. Interestingly the APOE2 gene  might explain  some of the research done on aged nuns (also ongoing) where some of the most advanced physical (brain damage) cases of Alzheimer’s had shown no signs of dementia during their lives. Perhaps the gene enables those who maintain an active healthy brain to rewire around the damage?

This is exciting research for brain building and seems to support much of the other research being done into brain function. We all need to maintain a healthy physical brain and use it as widely and create as much wiring as we can. The sooner we start this the better for old age!

This study was reported in the summer newsletter of the Neurological Foundation of New Zealand by Professor Claudia Kawas.She holds the Al and Trish Nichols Chair in Clinical Neuroscience and is professor of nneurobiology and behaviour and nneurology at the university of California, Irvine where she is principal iinvestigator of the 90+ study and associate director of the UCI Institute for memory impairments and neurological disorders. She is a geriatric neurologist and researcher in the areas of aging and dementia.