Scans can show beta amyloid, a protein associated with Alzheimer’s disease (right)
For the first time in 25 years, medical experts are proposing new diagnostic criteria aimed at better and earlier detection of Alzheimer’s disease (AD).
The guidelines, proposed by the National Institute on Aging (NIA) and the Alzheimer’s Association, update and revise the current Alzheimer’s criteria with modern technologies and the latest research advances.
According to the Alzheimer’s Association, an estimated 5.3 million Americans have AD, most of them 65 and older. The disease is thought to begin years, possibly even decades, before symptoms are noticeable. But there is no single, generally accepted way to identify the disease in its earliest stages before symptoms are evident.
The new diagnostic guidelines focus on advances in detecting biomarkers for the disease, such as substances found in spinal fluid or appearing on cutting-edge brain imaging scans conducted with PET or MRI.
Emphasis will be on diagnosing early stages of the disease as soon as possible so that patients can take measures to slow the progression or prevent further damage.
Allan Levey, MD, PhD
Allan Levey, MD, PhD, professor and chair of the Department of Neurology, Emory University School of Medicine, and director of the Emory Alzheimer’s Disease Research Center (ADRC) is an internationally recognized AD clinician and researcher.
Levey shares his thoughts and those of key members of the Emory ADRC related to the proposed diagnostic guidelines:
“The proposed changes could be useful and applicable in both clinical practice and in specialized research settings. The most important changes relevant to clinical practice are more simple criteria that can be used to diagnose dementia based on a careful history and examination, rather than requiring thorough neuropsychological testing which can be time-intensive, exhausting to patients, and not readily accessible to all patients.
The most extensive and exciting changes are the incorporation of biomarkers that can be measured in the spinal fluid or by advanced brain MRI and PET imaging methods. Inclusion of these new biomarkers is very likely to emerge as an important way to improve the accuracy of diagnosis in the near future. Their incorporation into the diagnostic criteria may offer accuracy comparable to autopsy but could be used while patients are still alive.  These biomarkers will also enable earlier diagnosis and more effective therapies. Application of these new methods is critical to advance clinical trials and essential for the development of preventive treatments.
While use of these biomarkers is now almost standard practice for clinical trials and other research studies, these biomarker-based methods are either not readily available or not approved for use in clinical settings, and they still need validation in clinical practice.”
The Alzheimer’s Association and the NIA have launched a web site at www.alz.org/research/diagnostic criteria to invite comments from the research community and other stakeholders until September 2010. The proposals will eventually be published in medical journals and tested in clinical trials.
