NEW YORK (GenomeWeb News) – Genetic biomarker-based tests designed to predict individual risk for Alzheimer's disease may be valuable in research projects and potential treatments, but they are not ready to provide valuable information for use in predicting disease risk in the clinic, according to a new set of Alzheimer's diagnostic guidelines issued Tuesday.
The National Institute on Aging and the Alzheimer's Association has incorporated decades-worth of new knowledge in its Diagnostic Guidelines for Alzheimer's Disease publication, which includes new ways of diagnosing the disease and risk earlier and when patients have milder symptoms. The new guidelines, updated and revised for the first time in 27 years, reflect the "major change" about how the disease is understood and viewed by experts, according to NIA.
Although several new methods to diagnose and monitor the disease, including tests using biomarkers, genetic risk tests for APOE e4, for example, currently are only useful for research purposes, according to the guidelines.
"Alzheimer's research has greatly evolved over the past quarter of a century," said NIA Director Richard Hodes said in a statement. "Bringing the diagnostic guidelines up to speed with those advances is both a necessary and rewarding effort that will benefit patients and accelerate the pace of research."
In its guidelines, NIA said that preclinical AD is an "emerging concept," but detection and tracking in this stage of disease could "have important implications for the development of effective treatments."
Using APOE e4–based tests or other tests using other biomarkers could speed up the progress of clinical trials for AD treatments, according to the guidelines, but regulators need to be assured that a given biomarker is "reasonably likely" to predict a clinically meaningful outcome before they should approve their use with treatments.
"We envision the time when the scientific means and accelerated regulatory approval pathway support multiple preclinical AD trials using biomarkers to identify subjects and provide shorter term outcomes, such that demonstrably effective treatments to ward off the clinical stages of AD are found as quickly as possible," the guidelines state.
While the guidelines conclude that "many questions remain to be answered" about how biomarkers may be used in diagnosing AD early, the progress made over the past two decades may be moving the field "toward earlier intervention, and ultimately, toward the prevention of AD dementia."