A group of medical researchers working at Georgetown University, the University of Rochester and UC-Irvine have developed a blood test which predicts with 90 percent accuracy if an individual will develop Alzheimer's disease or mild cognitive impairment (MCI) within three years. The test, which looks for a set of ten lipid markers, will allow treatments to be sought that may be effective during this early, asymptomatic stage of the disease.
Alzheimer's disease (memory-related MCI is thought to consist of early Alzheimer's symptoms) is a scourge ravishing the elderly among us, with 35 million currently afflicted worldwide, a number that is expected to grow to 115 million by mid-century. Alzheimer's is universally fatal, with life expectancy of about seven years after diagnosis. Diagnosis is generally indirect, largely based on symptoms and ruling out other causes of dementia.
There exist no treatments to cure or slow the inexorable progress of Alzheimer's. Some possibilities, however, have appeared in epidemiological studies, which show that people undergoing long term therapy with NSAIDS (non-steroidal antiinflammatory drugs) are less likely to develop Alzheimer's.
The lack of success in finding effective treatments may be that by the time a clear diagnosis can be made, the disease process is too far advanced to be interrupted. Medical researchers have previously found signatures of early Alzheimer's, but these have required examination of brain tissue or extraction of cerebrospinal fluid, preventing wide use as screening techniques.
The new blood test detects the breakdown products of nerve cell membranes. The signature is a set of ten metabolic products of such disintegration, two of which are highly specific for prediction of Alzheimer's. The test requires determination of the concentration of the ten lipid biomarkers, as all of them are seen in blood of test subjects who do not develop Alzheimer's or MCI. Carried out on the blood plasma, the current version of the blood test requires a good deal of special equipment (including mass spectrographs). Research is ongoing to develop a simpler version that can be used for clinical research, and eventually for screening purposes.
While the new Alzheimer's test has the potential for improving treatment and palliation of the disease, it will pose a new psychological hurdle associated with aging. Some people will want to know their fate, good or bad, so they can plan ahead for their future and the future of those close to them. Others will not be able to face the chance of discovering that they will experience the peculiar loss of self and dignity that is characteristic of Alzheimer's. We can only hope that effective treatment of incipient Alzheimer's disease is found.
Dr. Howard J. Federoff of Georgetown University outlines the research in the video below.
Source: Georgetown University
