September 02, 2008

Exercise May Help Prevent Age-Related Memory Loss

TUESDAY, Sept. 2 (HealthDay News) -- Exercise may help treat memory problems in adults, according to new research from Australia.

The study, focused on 138 people age 50 and older at increased risk for dementia, found that a home-based physical activity program led to modest improvements in cognitive function in adults with memory difficulties.

The participants -- who had memory problems but didn't meet criteria for dementia -- were randomly assigned to do the 24-week home-based physical activity program or to receive usual care.

Those in the exercise group were encouraged to do at least 150 minutes of moderate-intensity physical activity per week in three 50-minute sessions. Walking was the most frequently recommended type of activity. Participants in the exercise group did an average of 142 minutes more physical activity per week, or 20 minutes more per day, than those in the usual care group.

Over 18 months, participants in the exercise group had better Alzheimer Disease Assessment Scale-Cognitive Subscale (ADAS-Cog) scores and delayed recall, and lower Clinical Dementia Rating scores, than those in the usual care group. The ADAS-Cog consists of a number of cognitive tests.

The findings were published in the Sept. 3 issue of the Journal of the American Medical Association.

"To our knowledge, this trial is the first to demonstrate that exercise improves cognitive function in older adults with subjective and objective mild cognitive impairment. The benefits of physical activity were apparent after six months and persisted for at least another 12 months after the intervention had been discontinued. The average improvement of 0.69 points on the ADAS-Cog score compared with the usual care group at 18 months is small but potentially important when one considers the relatively modest amount of physical activity undertaken by participants in the study," wrote Dr. Nicola T. Lautenschlager, of the University of Melbourne, and colleagues.

"Unlike medication, which was found to have no significant effect on mild cognitive impairment at 36 months, physical activity has the advantage of health benefits that are not confined to cognitive function alone, as suggested by findings on depression, quality of life, falls, cardiovascular function, and disability," the researchers added.

They noted that the number of older adults with Alzheimer's disease (AD) could increase from the current 26.6 million to 106.2 million by 2050. If AD onset could be delayed by 12 months, there would be 9.2 million fewer cases of AD worldwide.

Exercise and other lifestyle factors may benefit older adults at risk for Alzheimer's disease, Dr. Eric B. Larson, of the Group Health Center for Health Studies in Seattle, wrote in an accompanying editorial in the journal.

"Health advances of the past century have led to more individuals surviving to extreme old age, when their risk of Alzheimer disease and related dementias increases substantially," Larson added. "Exercise -- and possibly other lifestyle factors -- appears to affect vascular risk and late-life brain health."

More information

The National Institute on Aging has more about memory loss.

-- Robert Preidt
SOURCE: American Medical Association, news release, Sept. 3, 2008
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