Researchers are looking for ways to spot early warning signs in the brain of developing Alzheimer's disease.

Baylor College of Medicine is taking part in a nationwide initiative, funded primarily by the National Institutes of Health, which uses neuroimaging techniques to understand the evolution of brain changes from normal aging to mild cognitive impairment and Alzheimer's disease. Finding early markers may lead to the advancement of treatments for patients with Alzheimer's disease and mild cognitive impairment, both of which cause memory loss in aging populations.

"What the study is meant to do is find out whether different types of neuroimaging are useful for following people over time and for tracking clinical changes in those people," says Dr. Rachelle Doody, a professor of neurology and director of the Alzheimer's Disease Center at Baylor College of Medicine in Houston. "If we can perform neuroimaging scans and pick out the markers of neurological disorders, even before there are clinically significant symptoms, we could treat patients earlier."

The National Institute of Aging, part of the NIH, will provide most of the $60 million in funding over five years to use neuroimaging in three groups of study participants - adults with mild cognitive impairment, Alzheimer's patients and a control group of people with no cognitive disorders - whose progress will be tracked for 2-3 years. The consortium includes approximately 50 institutions across the U.S. and Canada, with the University of California - San Francisco and UC - San Diego as the directing and coordinating sites, respectively.

The study will be the most comprehensive effort to date to examine such a large sample of patients with Alzheimer's disease and mild cognitive impairment using neuroimaging. In addition, potential biomarkers for Alzheimer's disease obtained from blood tests, urine samples, and in some cases, cerebrospinal fluid will be correlated with neuroimaging over an extended period of time. The study is also the first to use a publicly accessible data repository over the Internet, whereby researchers can compare results as the study progresses.

"It will not be like most studies where we have to wait until the very end for anyone to start looking at the data," said Doody, the principal investigator of the Baylor site. "Researchers will be able to access the data right away."

Doody says this particular study has the potential to trigger a number of advances in the field, ranging from improved early diagnosis to more efficient clinical trials and ultimately faster approval of new treatments.

"This study will address many of the deficiencies in our use and understanding of neuroimaging and dementia," Doody said. "We have to design ways to standardize our assessments, which is not an easy achievement because researchers do not really understand what the deficiencies in the field are right now."

"If we can find markers in people who have cognitive diseases even before they have symptoms, then we can design prevention trials in the future," she added.