From memory loss to dementia to Alzheimer's disease, people over 70 in U.S. are finding less difficulty with these problems, showed findings  online in the journal Alzheimer's and Dementia Wednesday.

Lead author Dr. Kenneth Langa and Dr. Allison Rosen, both of the University of Michigan Medical School in Ann Arbor, Mich., used data on 11,000 people from the Health and Retirement Study, a national survey of U.S. seniors age 70 and over.

The researchers compared data gathered in 1993 with data from 2002.

They found the rate of cognitive impairment, which includes a range of ills from significant memory loss to Alzheimer's disease, fell 3.5 percentage points between 1993 and 2002.

The researchers contributed the decline to the better education people received. The more education people had, the better they performed on cognitive tests.

Today's old adults are much likelier to have had more formal education, higher economic status, and better care for risk factors such as high blood pressure, high cholesterol and smoking that can jeopardize their brains.

The study reinforces other studies that suggest people who do mentally challenging tasks early on build up a reserve of brain power that helps them withstand later injuries to the brain, such as a mini-stroke.

In 1993, people who were 70 or older on average had 11 years of education. By 2002, those 70 and older had 12 years of education, according to the survey.

(Agencies via Xinhua February 22, 2008)