(PhysOrg.com) -- People who are not aware they are developing mild memory problems as they age may develop Alzheimer's disease at a faster rate than those who do notice their memory is slipping.
Studying the part of the brain that appraises and makes decisions could help predict who is at risk for rapidly advancing Alzheimer's disease, according to a University of Wisconsin School of Medicine and Public Health researcher.
"The disease is a significant public health concern with the number of cases rising dramatically," says Dr. Michele Ries, a neuropsychologist and researcher at the UW Alzheimer's Disease Research Center.
According to the Alzheimer's Association, 5.3 million Americans live with the disease. There will be half a million new cases this year alone.
In Ries' study, published by the Journal of the International Neuropsychological Society, a group of people with mild cognitive impairment (MCI) were compared to a group of healthy older adults. All were given a battery of neuropsychological tests and performed a series of tasks during functional magnetic resonance imaging (fMRI).
Ries found that the brain's cortical midline area showed activity during self-assessment exercises and that MCI participants with less insight into their impairment had considerably less brain activity than those who were aware of their mental difficulties. Ries says with mild cognitive impairment is always a precursor to Alzheimer's disease, but people with MCI don't always develop Alzheimer's.
"Anosognosia, or unawareness of function loss, is beginning to be recognized as an important clinical symptom of MCI, and with studies like this one, we are starting to understand how these symptoms develop," says Ries.
Alzheimer's disease causes memory problems and also makes it difficult for patients to carry out basic activities of daily living, while with mild cognitive impairment doesn't cause those kinds of problems. Ries says while there is some debate over whether there are memory difficulties that are associated with healthy aging, there is no clinical single tool that reliably distinguishes MCI from Alzheimer's disease.
Ries says health providers should be educated about the potential Alzheimer's disease connection to anosognosia and the safety concerns over those who are not aware of progressing impairment.
"You build a life, relationships, wisdom and knowledge. And then to have Alzheimer's disease take that all away in a gradual progressive fashion is a tragedy," says Ries.
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