Group Health study finds physical failings precede dementia

The earliest signs of dementia may not involve a decline in mental functions after all.

Instead, they're probably physical — a slowed gait, a failing sense of balance and a weakened handgrip, Seattle researchers have found.

In fact, older people who have those problems have triple the risk of dementia, including Alzheimer's disease, than those without those problems, according to the scientists from Group Health Cooperative, the Veterans Administration and the University of Washington.

"In aging, you don't want to separate the physical from the cognitive, because they are inextricably linked," said Dr. Eric Larson, the lead scientist in the research and director of the Center for Health Studies at Group Health.

"And if you can improve one, you're likely to improve the other, and vice versa."

The study by Larson, Li Wang of the VA Puget Sound Health Care System and UW researchers is the largest done on the physical precursors to dementia. It is reported in the current issue of Archives of Internal Medicine; it was funded by the National Institute on Aging.

The researchers kept tabs on nearly 2,300 Group Health members age 65 and older for six years, giving them physical and mental exams every two years. None had dementia at the start of the study. After six years, 319, or about 14 percent, had dementia, including 221 with Alzheimer's.

Overall, participants who had problems with their physical functioning at the beginning of the study had an increased risk of developing dementia and showed increased cognitive decline during the six years.

Specifically, poor standing balance and slowed walking were linked to an increased dementia risk. A poor handgrip was linked to the increased risk among people with possible mild cognitive problems.

More research is needed to confirm the findings and better understand them, the researchers said. But the scientists speculated in the report that "physical decline and cognitive decline may be inseparable during the development of dementia."

Previous research has shown that certain changes in the brain will affect both motor function and the hippocampus, a part of the brain that is the center of memory and closely associated with Alzheimer's.

Larson said no one knows precisely how long brain degeneration goes on before dementia becomes apparent. But many scientists believe it can take 10 years or longer. And research has shown that something can be done about it.

A study published by Larson and colleagues last January, for example, found that moderate exercise can delay dementia for many older adults, and the frailest may benefit the most.

Exercise improves blood flow to the brain, so brisk walks — even a couple of 15-minute strolls a day — can help a lot, Larson said.

"It's key that you don't assume you get enough exercise through everyday activities," he said. "You have to really exercise daily, just like you have to brush your teeth daily."

Exercising the mind — including reading, doing crossword puzzles, playing bridge — also helps stave off dementia, other research has shown.

Warren King: 206-464-2247 or wking@seattletimes.com