People aged 90 years or more who have poor physical performance have a higher risk of developing dementia, researchers from the University of California, Irvine, reported in Archives of Neurology. The authors mentioned walking, getting up from a chair, and standing with good balance as examples of a physical task.

The researchers explained, as background information that not many studies have focused on people aged 90 years or more. Prior studies had already pointed towards a link between poor physical performance and a decline in cognitive skills in younger seniors.

A study by researchers from the University of Edinburgh, Scotland, found that exercise may have a more protective benefit for the aging brain than leisure activities or mental pursuits. They found that participants in their 70s who did more exercise experienced less brain shrinkage and had fewer signs of memory and cognitive deficits compared to their inactive counterparts. The study was published in the 23rd October issue of Neurology.

Szofia S. Bullain, M.D., and team carried out a study on 639 participants, all aged at least 90 years. They gathered data from January 2003 to November 2009, which included details on their ages and cognitive levels. 72.5% of the participants were female – their average age was 94.

The authors wrote:

“Our cross-sectional study found a strong dose-dependent association between poor physical performance and dementia in the oldest old, with higher odds of dementia associated with poorer physical performance.

The results reveal that even modest declines in physical performance are associated with increased odds of dementia. The strongest association is seen with gait slowing, followed by five chair stands, grip strength and standing balance.”

The odds-ratios for each unit drop in a physical performance score were:

  • 1.7 for grip strength
  • 1.9 for standing balance
  • 2.1 for a 4-meter walk
  • 2.1 for chair stands

Those who could not walk at all, scoring zero, were nearly 30 times as likely to have dementia compared to the best able walkers.

Even those who slowed down in their walking speeds even slightly, up to 1.5 seconds, for example in a 4-meter walk, were four times more likely to have or soon develop dementia.

The researchers concluded:

“In summary, similar to younger elderly populations, our study found that poor physical performance is associated with increased odds of dementia in the oldest old. The establishment of this association may serve as a major stepping stone to further investigate whether poor physical performance is in the causal pathway and a potentially modifiable risk factor for late-age dementia.”

As people all over the world are living longer, WHO (the World Health Organization) is urging governments and health authorities to address the needs of elderly and very elderly people. WHO estimates that by 2050 over four-fifths of all seniors will be in developing countries; by that date there will be more people aged sixty years or more than fifteen or less. Elderly people are the fastest growing segment of global populations.

Chewing ability also linked to dementia risk – scientists at the Karolinska Institutet, Sweden, found that elderly people who maintain their chewing ability are less likely to develop dementia. Their study was published in the October issue of the Journal of the American Geriatrics Society.

Written by Christian Nordqvist