They also found that people who eat a Mediterranean-style diet have lower risks.
Mild cognitive impairment (MCI) refers to a group of symptoms in which people struggle with their ability to think and remember what they know. They often find it tricky to remember day-to-day things, but their memory troubles aren't severe enough to cause serious problems with everyday living.
Their decline in thinking and memory is greater than the typical slippage that happens with normal aging, although it's not as severe as with dementia.
Dementia refers to a group of symptoms that include severe memory loss and problems with thinking, solving problems, and using language. These problems are significant enough to affect a person's everyday life.
About 46% of people with MCI will get dementia within 3 years, compared to only 3% of people who have normal age-related thinking declines.
Millions of Americans have some type of dementia, including Alzheimer’s disease, according to the Alzheimer’s Association. This number is expected to grow in coming years.
The study, published in the American Journal of Psychiatry, reviewed 62 research studies to look for things that could indicate the risk of MCI worsening to dementia. Almost 16,000 people with MCI were included in these studies.
The researchers, led by Prof. Gill Livingston of University College London, found that in people with MCI:
- Diabetes seems to make it more likely that MCI will progress to dementia.
- Those who also have depression were at risk of MCI progressing to dementia, but evidence was inconclusive.
- Those with lower folate levels were more at risk of MCI eventually becoming dementia.
- People who are also lifelong heavy alcohol drinkers may be more likely to see MCI worsen to dementia. But moderate drinkers may be less likely than abstainers to progress to dementia.
"While there's currently no cure [for dementia], we know that the best way to reduce your dementia risk is to eat a Mediterranean diet rich in oily fish and vegetables, keep physically active, not smoke and have your blood pressure regularly checked," says Dr. Clare Walton, research manager at Alzheimer's Society in the U.K.