The statistics are startling and unnerving: Fill a room with 20 people in their 60s, and by current measurements, one person in that room will have Alzheimer's disease. But have them reunite
every five years and that number will consistently double, to the point that perhaps half will be afflicted by the time they're in their 80s.
With a cure for Alzheimer's still elusive, cognitive neuroscientist Marilyn Albert thinks the answers may lie not in the future, but in the past. By studying and following thousands of patients with common memory impairment over her distinguished career, Albert is piecing together which people will go on to develop full-blown Alzheimer's. Currently, it's very difficult to diagnose Alzheimer's before serious memory impact has occurred. Finding behavioral and biological markers that determine risk perhaps decades before onset could have profound implications.
"The reason accurate, early diagnosis is important is that,even though we don't currently have terribly effective drugs - drugs that reverse the disease's progression - we believe they will be found soon and that are going to be more effective if they're given early," says Albert. "It's also much easier for families to plan caregiving if they can get an accurate, early diagnosis.
From a humanistic point of view, that's crucial."
Albert, who directs the Division of Cognitive Neuroscience,is pursuing several lines of research with her colleagues. Traditionally, an Alzheimer's diagnosis has "been one of exclusion," says Albert. As in, if everything else from urinary tract infections to stroke to vitamin deficiency is ruled out in the case of progressive memory loss, the only thing left is Alzheimer's. Instead, Albert's group is looking for markers unique to the disease. Albert used to put patients through 10 tests of memory and executive function - the ability of the brain to multitask to accomplish a goal, such as preparing a meal with several dishes so they all come out hot at the same time. "Now I know, years later," she says, "that only two or three of those tests are any good," as a predictor of Alzheimer's onset.
On the biomedical side, by imaging the brain regions that Alzheimer's attacks early, Albert's group noted that the volume shrank as the disease progressed. Albert is now hoping to look at amyloid build-up in the brain. In the past, testing for amyloid increase, which is linked to Alzheimer's, could only be done after people had died. Now, with a PET scan and a substance known as PIB, it is possible to see when amyloid is present. The fact that 25 percent of people with increased amyloid don't yet have symptoms is leading researchers to examine mechanisms that may protect against the disease.
Albert intuits that only teamwork will yield real movement in her field. "We've been at this long enough to know the answers are not likely to come from one person in a lab doing work alone," she says. "Everyone believes you need an interdisciplinary team. You need expertise from different departments - neurology, psychiatry, neuropathology, radiology, molecular genetics - to solve this incredibly terrible disease."
And that's why, with her pick of institutions and more than 170 publications to her credit, Albert chose to continue her work at Johns Hopkins. "Certain environments," she notes, "lend themselves to collaborative interactions. Hopkins is one of those rare places."