Older people with mild cognitive problems may revert to normal brain function if they keep physically and mentally active and open to new experiences, say Australian researchers.
Professor Perminder Sachdev and colleagues from the University of New South Wales report their findings in the journal PLoS ONE.
"When people say 'I'm 70 or 75 and I'm having cognitive problems,' they worry it's impending dementia," Sachdev tells the Australian Broadcasting Corporation.
"What we're saying is it's not inevitable that it's going to get worse. Maybe there are things you can do to help."
Your risk of having a condition called mild cognitive impairment (MCI), which involves problems with memory and language, increases as you get older, says Sachdev.
He says these problems don't interfere with everyday functioning, but MCI is seen as a precursor to dementia.
Contrary to popular belief, Sachdev says evidence suggests around 1 in 4 people with MCI actually improve after their diagnosis, reverting to their original cognitive abilities.
"There are a certain proportion of people that get better."
To investigate factors influencing whether people with MCI reversed their cognitive decline, Sachdev and colleagues analysed data on 223 people, aged between 71 and 89 years, from the Sydney Memory and Aging Study.
The participants reported having difficulties such as remembering the names of people, or finding appropriate words, and cognitive tests confirmed that the participants had MCI.
Two years after the study began, the participants were tested again and 66 of them had reverted to normal levels of brain function.
"They are actually now performing at a better level than they did two years ago," says Sachdev.
The other participants had no change in impairment, or had a further decline in function.
Over the study period, Sachdev and colleagues also collected information on the participants' personality, lifestyle, physical and mental health (especially depression and anxiety).
The researchers found that people who reverted to normal functioning seemed to be aging 'better,' were more likely to have healthy blood pressure and had a better sense of smell and vision.
The 'reverters' were more physically and mentally active, but also had a more flexible personality that was open to new experiences, says Sachdev.
"These are usually people who are looking for variety. They are intellectually curious, have a more active imagination and are more creative.
"They go out to experience new environments, try new foods, think of alternative ways of doing things, and are sensitive to aesthetic values."
Sanchev says he can't exclude the possibility that the reverters had been misclassified and didn't actually have MCI in the first place.
"It's possible that on the day of the test they were having a bad day and performed badly," he says.
"But we think these are consistent factors that predict whether some of them improve. We think it's not just as artefact of measurement."