By a certain stage in life, most people show some signs of the odd memory blip or become a little forgetful.
The inevitable question often follows: “Is this the first sign of Alzheimer’s disease?”
Research published this week suggests it is more likely to be “mild cognitive impairment” that comes with natural ageing – and it can be countered by mild exercise.
The findings have prompted a new health guideline to be issued in the US, and a recommendation that exercise should be prescribed rather than medication by GPs for many older patients, as it may delay onset of Alzheimer’s disease and other forms of dementia.
More than 6 per cent of people in their 60s have mild cognitive impairment (MCI) across the globe, and the condition becomes more common with age, according to the American Academy of Neurology. More than 37 per cent of people 85 and older have it.
The new recommendation is part of an updated guideline for MCI published this week in the online issue of Neurology, the medical journal of the American Academy of Neurology.
"Regular physical exercise has long been shown to have heart health benefits, and now we can say exercise also may help improve memory for people with mild cognitive impairment. What's good for your heart can be good for your brain," said lead author Prof Ronald Petersen, director of the Alzheimer's Disease Research Center, Mayo Clinic and the Mayo Clinic Study of Aging in the US.
MCI is an intermediate stage between the expected cognitive decline of normal aging and the more serious decline of dementia. Symptoms can involve problems with memory; language, thinking and judgment that are greater than normal age-related changes.
Generally, these changes aren’t severe enough to significantly interfere with day-to-day life and usual activities. However, MCI may increase the risk of later progressing to dementia caused by Alzheimer’s disease or other neurological conditions, though some people with MCI never get worse, and a few eventually get better.
Six-month studies showed twice-weekly workouts may help people with mild cognitive impairment as part of an overall approach to managing their symptoms. The new guideline on MCI, which follows a review of all available studies, has been endorsed by the US Alzheimer’s Association.
Prof Petersen encouraged people to do aerobic exercise: “Walk briskly, jog, whatever you like to do, for 150 minutes a week 30 minutes, five times or 50 minutes, three times. The level of exertion should be enough to work up a bit of a sweat but doesn’t need to be so rigorous that you can’t hold a conversation. Exercising might slow down the rate at which you would progress from MCI to dementia.”
The guideline does not recommend dietary changes or medications. There are no drugs for MCI approved by the US Food and Drug Administration.
With such prevalence globally, “finding lifestyle factors that may slow down the rate of cognitive impairment can make a big difference to individuals and society,” Prof Petersen noted. “We need not look at ageing as a passive process; we can do something about the course of our aging,” he says. “So if I’m destined to become cognitively impaired at age 72, I can exercise and push that back to 75 or 78. That’s a big deal.”
Another guideline update says clinicians may recommend cognitive training for people with MCI. Cognitive training uses repetitive memory and reasoning exercises that may be computer-assisted or done in person individually or in small groups. There is, however, “weak evidence” that cognitive training may improve measures of cognitive function, the guideline notes.
The MCI guideline updates a 2001 academy recommendation. Prof Petersen was involved in the development of the first clinical trial for MCI and continues as a worldwide leader researching this stage of disease when symptoms possibly could be stopped or reversed.
