Elderly memory loss becoming less common
A new, nationally representative study in the US shows a downward trend in the rate of ‘cognitive impairment’ – the umbrella term for everything from significant memory loss to dementia and Alzheimer’s disease – among people age 70 and older.
The prevalence of cognitive impairment in this age group went down by 3.5% between 1993 and 2002 – from 12.2% to 8.7%, representing a difference of hundreds of thousands of people.
While the reasons for this decline aren’t yet fully known, the authors say today’s older people are much more likely to have had more formal education, higher economic status, and better care for risk factors that can jeopardise their brains, such as high blood pressure, high cholesterol and smoking.
The more-educated seniors who had cognitive impairment were more likely to die within two years. But the researchers say this may actually result from a protective effect of better education on a person’s ‘cognitive reserve’ – their ability to sustain more insults to their brain before significant thinking problems arise.
The study is published online in the journal Alzheimer’s and Dementia by a team led by two University of Michigan Medical School physicians and their colleagues. The study is based on data from the Health and Retirement Study (HRS), a national survey of older Americans funded by the National Institute on Aging and based at the UM Institute for Social Research (ISR).
Lead author Dr Kenneth Langa calls the findings good news for today’s seniors, noting that the new data support recent theories of how brains can be protected and preserved.
“From these results, we can say that brain health among older Americans seems to have improved in the decade studied, and that education and wealth may be a big piece of the puzzle,” says Dr Langa, an associate professor of internal medicine.
At the same time, the use of cholesterol-lowering drugs, blood pressure medications and other preventive cardiovascular medications and strategies increased dramatically in the 1990s. These factors may have helped protect seniors’ brain function by decreasing the incidence of vascular dementia – cognitive problems brought on by mini-strokes, strokes and decreased blood flow to and within the brain due to hardened or clogged arteries.
