50+: Live Better, Longer

Poor Self-Rated Health Linked to Dementia

Oct. 5, 2011 -- Think you're unhealthy? You could be right, and your brain may be trying to tell you something.

A new study shows that people aged 65 and over who rated their own health as poor were 70% more likely to develop dementia than those who felt they were in good health.

Researchers say the results suggest that poor self-reported health without any clear medical explanation may be an early warning sign of dementia.

"People don't yet complain of memory troubles, but still they have a feeling that something is happening in their brain or their bodies that is not right," says researcher Christophe Tzourio, MD, PhD, a professor at the University of Bordeaux 2 in France.

Dementia occurs when there is loss of memory and other mental functions such as reasoning and decision making. The most common cause of dementia is Alzheimer's disease.

"We do know that the biological changes associated with Alzheimer's disease are actually occurring 10, 15, and maybe even as much as 20 years before an individual has some of the cognitive or memory issues," says Heather Snyder, PhD, senior associate director of medical and scientific relations at the Alzheimer's Association.

"It could be these individuals are noticing changes in their memory or thinking and reasoning ability in those early stages but it's not enough to be picked up in clinical diagnosis," she says.

Rating Your Own Health

Researchers say previous studies have already shown that people who rate their own health as poor are more likely to die or develop a disease than those who consider themselves healthy. But few studies have looked at the implications of poor self-rated health on the risk of dementia.

In the study, researchers followed a group of 8,169 people in France aged 65 and over for an average of about seven years. The participants were asked to rate their own health at the start of the study and then were screened for dementia at the end of the study.

The people in the study were not in a hospital or living in other types of institutions.

The results, published in Neurology, showed those who rated their health as poor were 70% more likely to develop dementia than those who considered their health good. Those who rated their health as fair were 34% more likely to develop dementia.

Researchers found self-rated poor health was an even stronger predictor of future dementia risk in people without any memory problems. Those without any memory complaints who rated their health as poor were twice as likely to develop dementia as those who said their health was good.

The study also showed poor self-rated health was associated with an increased risk of dementia caused by Alzheimer's disease as well as vascular or stroke-related dementia.