A New Look at Diagnosing Alzheimer’s Disease

More than years ago, the National Institute of Neurological and Communicative Disorders and Stroke and the Alzheimer’s and Related Disorders Association (now the Alzheimer’s Association) released diagnostic criteria for Alzheimer’s disease (AD). At the time, AD was thought of only as a dementia. The 1984 criteria stated that the ultimate AD diagnosis was dependent on pathology. Since that time, the basic concepts of AD have changed significantly, and researchers have uncovered important clues on the diagnosis of AD and dementia. Updating Diagnostic Criteria for Alzheimer’s The National Institute of Aging of the NIH and the Alzheimer’s Association recently called a meeting to discuss whether or not the diagnostic criteria required updating. Three subgroups were established to discuss the criteria, based on what would be the biggest changes in the concepts of AD (Table 1). These included that AD starts years and perhaps decades before dementia develops and symptoms are visible. The result of this collaboration was the establishment of new guidelines based on four articles collectively called the “National Institute on Aging/ Alzheimer’s Association Diagnostic Guidelines for Alzheimer’s Disease.” The document was published in the April 22, 2011 online edition of Alzheimer’s & Dementia. “The field is changing rapidly, and the hope is biomarkers will become more widely available and used in diagnoses.” “The pre-symptomatic phase of AD includes people who have laboratory evidence of the disease but no symptoms,” explains Guy M. McKhann, MD, who was a member of the group that updated the diagnostic criteria. “The minimal cognitive impairment (MCI) phase includes people with memory problems who haven’t reached the stage of being demented. The final phase includes those...