Mayo Clinic renewed five more years as an Alzheimer's Disease Research Center

Thursday, July 15, 2004

The National Institute on Aging renewed Mayo Clinic's designation as one of the country's 29 Alzheimer's Disease Research Centers for an additional five years. The renewal comes with a $7.5 million grant to support research at Mayo Clinic in Jacksonville, Fla., and Rochester, Minn. Since 1991, Jacksonville investigators have been at the forefront of Alzheimer's research in African-Americans.

About 330 cognitively normal, African-American volunteers participate in important, ongoing research at the clinic. And although they have traditionally been underrepresented in Alzheimer's disease research, the disease is widely thought to disproportionately affect African-Americans. Many researchers have looked for differences in genetic predisposition without convincing results.

Mayo Clinic researchers believe if African-Americans are disproportionately affected, it may be because diseases, such as diabetes and hypertension, which may put people at risk for developing Alzheimer's, affect African-Americans more than other racial groups. They also believe that standardized neurocognitive tests probably contribute to misdiagnosing numbers of African-Americans. Physicians use these tests to help them diagnose Alzheimer's by comparing a person's cognitive abilities to what's considered normal. However, data for determining what normal memory is for older African-Americans did not exist. So Mayo Clinic researchers, working with their large group of volunteers, determined soon-to-be-published standards.

As they've recruited cognitively normal, older African-Americans to participate in this research, Mayo Clinic physicians have also provided free dementia evaluations and follow-up treatment for more than 350 African-Americans. One of them was Jane Freeman.

In the early 1990s, Pamela Quarles began noticing changes in her mother's behavior that she couldn't attribute to normal forgetfulness that comes with age. "You hope against hope that it wasn't going to be what you thought it was going to be," Quarles says. "Unfortunately it was." Freeman was diagnosed at Mayo Clinic with probable Alzheimer's. She was treated and followed until her death in May by Mayo Clinic neurologist Dr. Neill Graff-Radford and family practice physician Dr. Floyd Willis.

Freeman's husband committed to taking care of his wife at home until he, too, became ill. Then Quarles began taking care of both her parents. "For awhile I literally ran a hospital in their home," she says. "It was 24/7 care. Dr. Graff-Radford and Dr. Willis were great. Having them as a sounding board and being able to call them if we were having a crisis was invaluable."

Quarles says unfortunately her father, who predeceased his wife, denied she had a problem for too long. If Freeman had been diagnosed sooner, she may have benefited from some of the newer treatments for early-stage Alzheimer's.

Willis and other researchers are beginning to study early memory loss, in part, for that reason. Now that there are standards defining what normal memory is in older African- Americans, Willis wants to know if early memory loss is the beginning of Alzheimer's. If it is, by identifying these people early, they'd be the ones to benefit most from existing or yet-to-be-discovered therapies that slow progression of the disease.

On the other hand, Willis says knowing that early memory loss isn't due to the Alzheimer's disease process can help direct physicians to the real cause. "As a primary care physician it's extremely important to me," he says. "That's because significantly more African-Americans are theorized to have memory problems from little strokes. Where do these little strokes come from? Hypertension and diabetes. So if there are large numbers of African-Americans who actually have their memory loss because of these small strokes, that's significant, because you can fix these problems. We can't yet arrest and correct Alzheimer's disease, but it is possible to correct hypertension and diabetes, or at least find them much earlier before they start causing problems."

Willis says people generally don't know if a slight memory problem is part of normal aging or if it could be a sign of dementia. "One way to gain insight is to decide whether a memory problem is worse than in friends and relatives who are the same age," Willis says. He is currently enrolling African-Americans over 70 in such a study. If individuals are getting complaints about their memory from friends or relatives, they might consider calling Mayo Clinic to find out how to participate in the study. Those interested may call (904) 953-2677.

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