Scientists at 26 Alzheimer's Disease Centers have collaborated on a study that concludes that a test for a form of an Alzheimer's-related gene, called ApoE, when administered after an initial clinical evaluation, reduces the number of false positive diagnoses of Alzheimer's disease by approximately 30 percent. The researchers, who were supported by the National Institute on Aging (NIA), also reported that testing only for the E4 form of the gene, although strongly associated with Alzheimer's disease, is not sufficient to be used as a diagnostic tool by itself. In fact, nearly 40 percent of Alzheimer's patients with a confirmed diagnosis did not have the E4 form of the APOE gene.
The researchers suggest that, following a thorough evaluation by a trained physician and using recommended criteria and other diagnostic tests such as MRIs, a test for the E4 form of ApoE might be a helpful supplemental tool for physicians trying to make clinical diagnoses of different types of dementias. According to Dr. Creighton Phelps of the NIA, "we cannot underestimate the usefulness of increasing a physician's confidence in diagnosing a disease of this magnitude. When facing a family who must bear the weight of such devastating news, most doctors would appreciate as many tools as possible to help them in their certainty of diagnosis. ApoE testing may be such a tool."
The study appears in the February 19, 1998 issue of The New England Journal of
Medicine and represents the largest cooperative investigation to date among 26
Federally-funded U.S. Alzheimer's Disease Centers (ADCs). Dr. Phelps, who
supervises the ADCs Program for the NIA, points out that the ADCs have been
established by the NIA over the past 15 years at academic institutions
nationwide to enroll patients for research studies related to Alzheimer's
disease in the hope of improving diagnosis, and to create and test new therapies
for the disease. F
Contact: Michael Miller
NIH/National Institute on Aging