A Very Precious Gift of Time
Alzheimer's patients, with no cure in sight, still benefit from an early diagnosis
Unpreventable, incurable, and largely untreatable--that's the grim picture of Alzheimer's disease. But, surprisingly, patients who find out they have the illness are not completely lost in the dark. "I've spent the past year and a half sitting with these people," says Renee Beard, a medical sociologist at the University of California-San Francisco. "Yes, they're afraid when they hear the news. But they see positive things, too: They have time to plan, to take vacations with their families, to find support groups. And they're grateful for the time to do all this."
To gain that precious time, the disease needs to be detected--and the sooner the better. Last week, at a major Alzheimer's research conference in Washington, D.C., doctors described simple, five-minute tests that general physicians can use to screen people for possible signs of the disease--something few doctors do now. Scientists also highlighted new ways to scan for Alzheimer's years before obvious symptoms appear: by measuring changes in the brain. Raising these prospects for detection has also raised researchers' optimism, even if medical options are limited. "If we want to be able to intervene as early as possible, we need to be able to identify people who are at high risk," says Marilyn Albert, codirector of the Johns Hopkins Alzheimer's Disease Research Center in Baltimore.
Early warnings. Identifying such people nearly a decade before their memories begin to go is a promising start, and that's what a new type of positron emission tomography scan, or PET, seems able to do. It focuses on energy levels in the hippocampus, a brain region crucial to memory. Lisa Mosconi and Mony de Leon, brain researchers at New York University, and their colleagues took 53 people, ranging in age from 50 to 84, who showed no overt signs of dementia, and gave them scans. The scientists were then able to follow some of these people for many years. Eventually, 19 of them showed signs of mild cognitive impairment, a precursor of Alzheimer's, and another six developed Alzheimer's itself. And when Mosconi went back and looked at the PET scans, the energy in the hippocampus was indeed lower in the people who became ill. The scans, taken an average of nine years before diagnosis, predicted mild impairment with an accuracy rate of 71 percent and Alzheimer's with an accuracy rate of 85 percent.
"If I had 100 patients, I'd be able to accurately predict who is going to get sick and who is going to stay normal in 85 of them, nine years in advance," Mosconi says. "That's pretty good." At the moment, this kind of advanced PET is not ready for the doctor's office; it's best suited for evaluating drug effectiveness in research trials.
What is being used in the doctor's office right now is not working very well. General physicians are the doctors most likely to see someone just beginning to show Alzheimer's. "Unfortunately, few physicians actually screen their patients for the disease," says Henry Brodaty, a neuropsychiatrist at the University of New South Wales in Australia. Only about a third administer simple memory tests in their offices. Since available Alzheimer's drugs like Aricept work better the earlier they are given, this is a lost window of opportunity.
The problem, Brodaty says, is that the most common office test, the Mini-Mental State Examination, takes about 10 minutes to give. "Since the average office visit doesn't last much longer than that, physicians just don't have the time," he says. So after searching scientific literature, Brodaty came up with three other tests that are as accurate as the Mini-Mental. All of these tests ask the patient to recall the names of a few items and sometimes to draw something like the hands of a clock. So what's the advantage? "Five minutes," says Brodaty. "These other tests take five minutes or less to give, so doctors should have an easier time fitting them in." If a test indicates memory problems, the patient can be referred to a memory clinic for more-specialized testing to confirm the diagnosis.
Once people hear the diagnosis, Beard's study showed, they do show fear, and shame, and they worry about things like losing their driver's licenses. Yet there were positive reactions, too. "With support groups, I no longer feel like I'm in it alone," one man told her. And, said another, "I was just glad to know what was causing my problems. Now I could do something about it."
This story appears in the July 4, 2005 print edition of U.S. News & World Report.
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