About two in 10 people over the age of 65 have mild cognitive impairment, such as a noticeable change in memory, problem-solving ability, or attention.
This deterioration is caused, in part, by the same brain changes that occur in dementia.
While mild cognitive impairment often has little effect on a person’s lifestyle, between 5% and 10% of those who suffer from it will develop dementia.
Why some people with mild cognitive impairment develop dementia and others has not been a long-standing mystery.
But a recent study from Columbia University in New York identifiedor various factors that determine whether a person is more or less likely to develop mild cognitive impairment.
These findings could give us a clue as to who is most likely to develop dementia.
The researchers looked at 2,903 people 65 and older and tracked their brain function for nine years.
To detect cognitive impairment, it was observed whether the participants undiagnosed with dementia had problems with a memory exercise or if they had reported difficulties with certain daily tasks (such as using the telephone).
At the beginning of the study, all the participants had normal brain function. After six years, 1,805 participants had normal cognitive function, 752 had mild cognitive impairment, and 301 had dementia.
The researchers then followed the cognitively impaired group for another three years.
Because some participants were “lost to follow up,” the researchers were only able to look at 480 people from the original group with mild cognitive impairment.
While 142 still had mild cognitive impairment, they found that 62 people in this group now had dementia.
The researchers also found that 276 people no longer met the criteria for mild cognitive impairment, showing us that mild cognitive impairment does not always lead to dementia and is not necessarily permanent.
Let’s first look at the factors related to a lower risk of developing mild cognitive impairment.
Lower risk
one. Education
Time spent on education is a factor that reduces the risk of mild cognitive impairment.
People who had studied for an average of 11.5 years were 5% less likely to develop mild cognitive impairment than those who had studied for 10 years.
The study does not differentiate between the type of education (primary school or higher education).
One theory for this link is that longer time in education is related to higher socioeconomic status, which may mean that a person has access to a healthier lifestyle and better healthcare.
Another theory is that education helps the brain build more neurons and connections. This can help the brain compensate for any changes that occur from mild cognitive impairment, such as memory loss.
two. Exercise and leisure activities
People who were more physically or socially active had a slightly lower risk of developing mild cognitive impairment.
To measure how social or active the participants were, they completed a questionnaire about the type and frequency of activities they did, such as walking or going to the movies.
The researchers gave the participants a maximum score of 13. The higher the score, the more active the participant was.
Those with no mild cognitive impairment scored an average of 7.5, while those with mild cognitive impairment scored slightly lower, 7.4.
People with dementia scored 5.8.
Previous studies have also shown that activity physical moderate intensity (such as swimming) during middle age or old age can reduce the risk of mild cognitive impairment.
The protective effect of exercise could be explained by structural changes beneficial that occur in our brain as a result of physical activity. There is also growing evidence that participating in social activities can help maintain brain health and reduce the risk of premature death.
3. Entry
People earning more than $ 36,000 a year were 20% less likely to develop mild cognitive impairment compared to those earning less than $ 9,000 a year.
Income is probably related to a lower risk of cognitive decline for reasons similar to education. People with higher incomes have more likely to pay for better healthcare and to have a healthier diet and lifestyle.
They can also live in areas where environmental factors, such as pollution, have less of an effect on them.
This is important, as there are increasingly evidence that contamination may be related to conditions such as tolzhandimer and the parkinson.
Higher risk
Researchers at Columbia University also identified several factors associated with an increased risk of developing mild cognitive impairment.
These factors include:
one. Genetics
It was found that the presence of allele AP0E E4 (one of two or more versions of a gene) increases the risk of developing mild cognitive impairment by 18%.
This finding is consistent with previous evidence that also shows that this allele may increase the risk of dementia.
People with AP0E E4 are about three times more likely to develop Alzheimer’s disease than those with a different variant of the AP0E gene.
The reason, scientists believe, is that this variant makes people are more likely to accumulate toxic protein deposits in the brain, a feature of Alzheimer’s disease.
Researchers also believe that this gene only causes damage in old age.
two. Underlying health problems
People with one or more chronic health conditions, such as heart disease, depression or diabetes, have a 9% higher risk of developing mild cognitive impairment, according to researchers from Columbia University.
The increased burden of various health conditions could lead a person to become less involved in their usual daily activities or social life. Both changes in behavior can accelerate the decline in brain health.
Other conditions, such as heart disease, are also known to increase the risk of cognitive decline.
“Our brains are dynamic”
This study reminds us that mild cognitive impairment is not necessarily a prelude to dementia.
In fact, some study participants with mild cognitive impairment returned to normal brain function.
It’s not entirely sure why, but could be due to lifestyle changes after diagnosis (such as exercising more) that may have improved the results.
It could also be that some participants were misdiagnosed at the beginning of the study, but this is unlikely given the wide range of tools used to confirm their diagnoses.
Our brains are dynamic and keeping them active throughout our lives is important to maintaining good brain function.
While there are some risk factors, such as our genes, that we cannot change, stay active and lead a healthy lifestyle it can be a way of reducing our risk of mild cognitive impairment and dementia.
*This article originally appeared on The Conversation. You can read the original version and see the vlinks to all scientific studies mentionedhere.
Mark Dallas is Associate Professor of Cellular Neuroscience at the University of Reading in the UK.
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