People aged 90 and older who have difficulty with walking and other physical skills are more likely to have dementia, a new study finds.

The research included 629 people who underwent various tests of their physical abilities. The average age of the participants was 94 and 72.5 percent of them were women.

The tests included a 4-meter walk (about 13 feet), standing from a chair, standing balance and grip strength. The worse the participants did on these physical tests, the more likely they were to have the loss of mental skills known as dementia.

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For example, those who were unable to walk were nearly 30 times more likely to have dementia than those with the fastest walking times. Even minimal slowing in walking speed was associated with a four times greater likelihood of having dementia.

"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," wrote Dr. Szofia Bullain and colleagues from the University of California, Irvine.

The study was published online in the journal Archives of Neurology. Previous research has suggested a link between reduced physical abilities and memory and thinking (cognitive) problems in younger seniors.
Further research is needed to determine whether declining physical abilities contribute to cognitive decline and are a modifiable risk factor for late-age dementia, the study authors concluded.

The study found an association between older adults' physical skills and presence of dementia, but it did not prove cause-and-effect.