(Agencies)
Updated: 2007-12-29 17:08

NEW YORK - Results of a brain autopsy study indicate that most older adults have significant brain pathology (disease), regardless of the presence or absence of outward signs of dementia.

An elderly man in a file photo. Forgot where you put your keys? Or your car? If you are over 60, it may just be a normal part of aging, US researchers said on Wednesday in a study that suggests brain structures deteriorate with age in otherwise healthy people. [Agencies]

As part of the long-term Rush Memory and Aging Project, researchers evaluated the spectrum of abnormalities found in the brains of 141 older adults, with and without clinically evident dementia.

At the time of death, only 20 persons (14.2 percent) were free of brain disease, Dr. Julie A. Schneider, from Rush University Medical Center, Chicago, and colleagues found.

Most older persons with dementia (i.e., memory and other cognitive impairments) had more than one type of pathology in their brain causing the impairment, Schneider told Reuters Health.

"This most commonly was Alzheimer's disease pathology and cerebral infarcts (strokes), followed by Alzheimer's disease and Lewy body disease, a disease related to Parkinson's disease," she said.

Older persons without dementia also frequently had brain disease, most commonly Alzheimer's-like disease, but also multiple other abnormalities, Schneider noted. Having more than one disease in the brain significantly increased the likelihood that symptoms of dementia will be present.

"Older persons can often handle one pathology in their brain, but the burden of more than one pathology may tip them over the threshold of clinical dementia," Schneider said.

Therefore, prevention of not only Alzheimer's disease but these other pathologies, particularly stroke and those things that may increase the risk of stroke, like high blood pressure, high cholesterol, cigarette smoking, obesity, "are likely to significantly decrease the prevalence of dementia," Schneider added.

The findings are published in the journal Neurology.

Based on this study, write two neurologists in an accompanying editorial, "we may wish to maximize medical management of vascular risk factors in the growing elderly population, regardless of whether cognition is still normal or there are signs of overt dementia."