Brighter Odds of Beating Memory Loss

Feb. 20, 2008 -- The chance of avoiding severe memory loss after age 70 may be better than you think.

"This is good news for aging baby boomers," Kenneth Langa, MD, PhD, associate professor of medicine at the University of Michigan and the Ann Arbor VA Health System, tells WebMD.

Langa's team studied cognitive impairment among people aged 70 and older in the U.S. not living in nursing homes or other institutions. The researchers defined cognitive impairment as memory loss on a scale similar to that seen in dementia -- not mild memory loss.

For the study, some 7,400 people took memory tests in 1993. About 7,100 other people took the same tests in 2002.

"What we found is that the risk for someone who was 70 and older in 1993 of having impaired cognition was higher than the risk for someone in that same age group in 2002," says Langa.

Schooling, Heart Health

The study doesn't show why serious memory loss was less likely among the later generation. But Langa's team has some theories.

"We think the decrease in the risk that people would become significantly impaired or get dementia is due to a few things: the significant increase in education level between the two cohorts and also likely a better job of treating cardiovascular risks like hypertension and high cholesterol," says Langa.

In short, more education may help keep the brain sharp, and tending to heart health can be good for the brain. Other factors also affect brain health; Langa and colleagues didn't have data on all of those factors.

Big Picture

The findings are all about individual risk. But even with a lower individual risk, Langa foresees a rise in Alzheimer's and other dementia cases.

That's because the U.S. population is aging. About 80 million baby boomers will reach age 70 in the next eight or 10 years, and with an aging population, "there's going to be a large increase in the number of people with Alzheimer's disease and dementia, even with a decreased [individual] risk," says Langa.

That is, individual risk may be lower than in the past, but there are many more individuals, so the net result is more cases. Last year, another report predicted that Alzheimer's cases will triple by 2050.

Langa notes that further studies are needed on cognitive impairment among people in nursing homes. Meanwhile, Langa's current study appears online in Alzheimer's & Dementia.