Alzheimer's diagnostic guidelines updated

WASHINGTON, April 19 (UPI) -- For the first time in 27 years, clinical diagnostic criteria for Alzheimer's disease have been revised, but only for researcher purposes, U.S. officials say.

The National Institute on Aging/Alzheimer's Association Diagnostic Guidelines for Alzheimer's Disease are a major change in how experts think about and study Alzheimer's disease.

Dr. Richard J. Hodes of the National Institute on Aging says the guidelines -- largely for the purposes of research -- describe three distinct stages of Alzheimer's disease:

-- The preclinical stage. Brain changes, including amyloid buildup and other early nerve cell changes, may already be in process, but symptoms are not yet evident.

-- Mild cognitive impairment with symptoms of memory problems, enough to be noticed and measured, but not compromising a person's independence. Patients may or may not progress to Alzheimer's dementia.

-- Alzheimer's dementia. A decline in cognition occurs, such as word-finding. Vision/spatial issues and impaired reasoning or judgment may be the first symptom to be noticed.

The guidelines, published in Alzheimer's & Dementia: The Journal of the Alzheimer's Association, were developed by expert panels convened last year by the National Institute on Aging, part of the National Institute of Health and the Alzheimer's Association.