A frail person, for instance, won't likely bounce back from a bout of influenza or an emotional setback, such as the death of a loved one, as easily as a stronger older person.
"This means that even a minor insult, such as an infection or illness of a caregiver, can tip the balance and cause a cascade of adverse events to the extent that the person is unable to function in their usual environment and may require hospital admission or residential care," Heppenstall said.
In a study published in the October issue of the Journals of Gerontology Series A: Biological Sciences and Medical Sciences, Fried and her research team found that three or more bodily systems functioning at abnormal levels was a predictor of which people would be frail. They looked at such factors as anemia, inflammation and fine motor speed. By itself, fine motor speed also predicted frailty, the study found.
So is frailty inevitable? Eventually, if people live long enough, it's likely they will become increasingly frail. But "it can be delayed," Brangman and others said.
Much of it is rooted in unhealthy habits picked up in early and middle age -- "especially a lack of physical exercise, smoking and poor nutrition," said Heppenstall.
"To prevent it, we should emphasize regular physical activity in all adults at all ages, as well as a balanced diet," she said.
Exercise on a regular basis will at least delay frailty, agreed Brangman. "What we are trying to do is avoid that period of time when people are dependent and debilitated and have a lot of disability and need to be institutionalized."
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