Ability to Identify Celebrities Might Uncover Early Alzheimer's

If you're 65 or older, how well can you identify a photo of movie star John Wayne or singer Kate Smith? And can you recall the names of more recent celebrities, such as Leonardo DiCaprio or Martha Stewart?

At the Medical College of Wisconsin, researchers are using older patients' ability to recognize celebrities and advanced imaging technology to help identify - or rule out - Alzheimer's at an earlier and more treatable stage.

"Our goal is to identify the earliest brain abnormalities associated with Alzheimer's, as much as 10 or 15 years before patients are diagnosed," says Stephen M. Rao, PhD, Professor of Neurology and Neuropsychology at the Medical College and Director of the Functional Imaging Research Center. "By detecting the disease at an earlier stage, it may be possible to prevent or delay the brain changes with novel drug therapies. If you could delay the onset by just five years, it is possible to prevent 50% of deaths from Alzheimer's."

After cancer and heart disease, Alzheimer's is the most common cause of death in the United States and the most expensive illness to care for.

Dr. Rao's study subjects are healthy volunteers 65 and older both with and without memory problems. Using functional magnetic resonance imaging (fMRI), he and his colleagues scan the volunteers' brains to measure neural activity involved in long-term memory.

The Medical College was one of three medical centers to pioneer the development of fMRI technology in the early 1990s. fMRI uses magnetic resonance imaging to measure tiny metabolic changes that take place when areas of the brain become active as people perform a task in the scanner. By knowing the general areas of the brain where speech, sensation, movement, memory and other cognitive functions originate, physicians can pinpoint the exact locations of the brain affected by injuries and disease.

Recent Events, Names More Difficult to Retain
For Dr. Rao's study, which is funded by a $1.8 million grant from the National Institute on Aging plus additional funding from the Advancing a Healthier Wisconsin initiative, patients are scanned while being shown images of celebrities from different eras and pictures of unfamiliar individuals. Patients are asked to determine if the person is famous or not.

In the normal brain, when patients are shown images of famous people, two areas of the brain become active: the medial temporal lobe and the posterior cingulate gyrus in the parietal lobe. No activity is seen in these brain structures when a person is shown an unfamiliar face. If damaged by injury or disease, these structures can result in severe memory loss. It is these precise structures that are the first to be affected by Alzheimer's disease, Dr. Rao says.

Because the scan can pick up these areas of altered activation long before a noticeable decline in memory becomes apparent, Dr. Rao and his colleagues hope the results can help identify the disease early and lead to preventive treatment long before patients exhibit symptoms.

Dr. Rao is also Chief Science Officer of Neurognostics, a company using fMRI technology developed at the Medical College and patented by the MCW Research Foundation. Neurognostics is conducting research, in partnership with pharmaceutical companies, to determine the effectiveness of fMRI for evaluating new therapies.

Who's At Risk?
Alzheimer's is a progressive disorder that causes memory loss. It afflicts an estimated 4.5 million people in the United States and millions more globally. In its later stages, patients lose other functions.

The major risk factor for Alzheimer's is age. The risk of Alzheimer's nearly doubles every five years; by age 95 nearly 50% will have Alzheimer's disease. At 65 to 70, the risk is about 1.5%. Between 70 and 74, the risk rises to about 3.5%. From 75 to 79, the risk goes up to about 6.8%.

Subjects in Dr. Rao's study are between the ages of 65 and 85, have not experienced memory loss, and fall into three groups: those with no risk factors for developing Alzheimer's, those at risk because they have a close family relative with Alzheimer's, and those who might be at risk because of a genetic predisposition to Alzheimer's by virtue of having the epsilon 4 allele of apolipoprotein E (ApoE), a gene that helps metabolize cholesterol. A fourth group consists of patients who have begun to experience memory problems but do not yet meet criteria for Alzheimer's.

Other conditions can mimic Alzheimer's. For instance, depression, which is common in the elderly, may include Alzheimer's-like symptoms, such as forgetfulness and withdrawal. In addition, there are other forms of dementia, although Alzheimer's is by far the most common. Other types of dementia may result from vascular and alcohol-related causes.

Detecting Alzheimer's at an earlier stage and developing drugs that can postpone its effects is an area of keen interest by the National Institute on Aging (one of the National Institutes of Health), Dr. Rao says. His work is one of a number of areas of research into Alzheimer's disease taking place at the Froedtert & the Medical College.

In the Neurology Department, where the Memory Disorders Clinic is located, researchers are conducting clinical trials and testing other options for treatment and earlier diagnosis of Alzheimer's. And since 1986, Medical College researchers have been studying early-life risk factors that may predict who is likely to develop Alzheimer's. Subjects for this research include nuns from the School Sisters of Notre Dame. A goal of this research is to help pinpoint risk factors, unrecognized today, that may cause the development of Alzheimer's disease.

Those interested in participating in Dr. Rao's study may obtain further information by calling 414-456-4492.

Barbara Abel
HealthLink Contributing Writer

MCW Health News presents up-to-date information on patient care and medical research by the physicians of the Medical College of Wisconsin.