Effective treatments for Alzheimer's disease appear several years away at best. But, in what could be considered a painful irony, scientists have become increasingly adept at spotting the illness in its earliest stages. Magnetic resonance imaging, PET scans, spinal fluid analyses and other techniques have enabled physicians to reliably detect the disease -- often years before symptoms appear.
These detection methods identify mild cognitive impairment, a condition that many scientists consider a high-risk precursor to Alzheimer's disease. The impairment is marked by a pattern of forgetfulness that's unusual for the person, though it doesn't necessarily interfere with daily activities. Of the several million Americans thought to have the condition (the figure might be higher because it can be written off as common aging), roughly 15% advance to full-fledged Alzheimer's every year. "Even since five years ago, there's been a huge technical jump," says Dr. William Jagust, a professor of public health and neuroscience at UC Berkeley. "I think for the first time, we have the idea that we might be able to predict what happens to normal older people who aren't having symptoms -- to predict who among that group is destined to develop Alzheimer's disease could be possible."
