The research found that among 85 participants in the study with mild cognitive impairment, those with low scores on a memory recall test and low glucose metabolism in particular brain regions, as detected through positron emission tomography (PET), had a 15-fold greater risk of developing Alzheimer's disease within two years, compared with the others in the study.
The results, reported by researchers at the University of California, Berkeley, on Tuesday, July 14, at the Alzheimer's Association 2009 International Conference on Alzheimer's Disease in Vienna, Austria, are a major step forward in the march toward earlier diagnoses of the debilitating disease.
"Not all people with mild cognitive impairment go on to develop Alzheimer's, so it would be extremely useful to be able to identify those who are at greater risk of converting using a clinical test or biological measurement," said the study's lead author, Susan Landau, a post-doctoral fellow at UC Berkeley's Helen Wills Neuroscience Institute and the Lawrence Berkeley National Laboratory.
"The field, in general, is moving toward ways to select people during earlier stages of Alzheimer's disease, including those who show no outward signs of cognitive impairment," said Dr. William Jagust, a faculty member of UC Berkeley's Helen Wills Neuroscience Institute and principal investigator of the study. "By the time a patient is diagnosed with Alzheimer's disease, there is usually little one can do to stop or reverse the decline. Researchers are trying to determine whether treating patients before severe symptoms appear will be more effective, and that requires better diagnostic tools than what is currently available."
In the latest study, researchers compared a variety of measurements that had previously shown promise as early detectors of Alzheimer's. The measurements included scores on the Auditory Verbal Learning Test; the volume of the hippocampus, the part of the brain associated with the formation of new memory; the presence of the apolipoprotein E4 gene, which has been linked to increased risk of Alzheimer's; certain proteins found in the cerebrospinal fluid; and glucose metabolism detected in PET brain scans. A low rate of glucose metabolism in a particular brain region is considered a sign of poor neural function, most likely due to the loss of synapses in that area.
"What's really novel about our study is that we evaluated all of these biomarkers in the same subjects, so we could more easily compare the predictive value of any one measure over the others," said Landau. "The Auditory-Verbal Learning Test, which measures memory recall ability, and the PET scans measuring glucose metabolism were the two markers that clearly stood out over the others."
The researchers pointed out that other measurements - in particular, hippocampus volume and the cerebrospinal fluid markers - also showed promise in predicting disease progression. However, when considering all the measurements together, PET scans and memory recall ability were the most consistent predictors. The researchers expect to have more complete information about which measures serve as the best predictors in a year as they continue to gather data for this ongoing study.
An earlier study led by Jagust, a professor with joint appointments at UC Berkeley's School of Public Health and the Lawrence Berkeley National Laboratory, found that PET scans and magnetic resonance imaging (MRI) could detect neurological changes in asymptomatic people who subsequently developed dementia or mental impairment, although it was too soon to say if those people would go on to develop Alzheimer's.
The research is part of the nationwide Alzheimer's Disease Neuroimaging Initiative, a 60-center study funded by the National Institute on Aging. The ultimate goal of the initiative is to find a biomarker for Alzheimer's that would predict individuals who will later develop Alzheimer's disease. Ideally, this marker would be identifiable very early, even in individuals who do not yet show signs of mental impairment.
Jagust heads the initiative's research on PET imaging. The UC Berkeley study includes those patients who had measures for all biomarkers.
Sarah Yang | EurekAlert!
Scientists develop tiny tooth-mounted sensors that can track what you eat
22.03.2018 | Tufts University
NIH scientists describe potential antibody treatment for multidrug-resistant K. pneumoniae
14.03.2018 | NIH/National Institute of Allergy and Infectious Diseases
An international team of researchers has discovered a new anti-cancer protein. The protein, called LHPP, prevents the uncontrolled proliferation of cancer cells in the liver. The researchers led by Prof. Michael N. Hall from the Biozentrum, University of Basel, report in “Nature” that LHPP can also serve as a biomarker for the diagnosis and prognosis of liver cancer.
The incidence of liver cancer, also known as hepatocellular carcinoma, is steadily increasing. In the last twenty years, the number of cases has almost doubled...
In just a few weeks from now, the Chinese space station Tiangong-1 will re-enter the Earth's atmosphere where it will to a large extent burn up. It is possible that some debris will reach the Earth's surface. Tiangong-1 is orbiting the Earth uncontrolled at a speed of approx. 29,000 km/h.Currently the prognosis relating to the time of impact currently lies within a window of several days. The scientists at Fraunhofer FHR have already been monitoring Tiangong-1 for a number of weeks with their TIRA system, one of the most powerful space observation radars in the world, with a view to supporting the German Space Situational Awareness Center and the ESA with their re-entry forecasts.
Following the loss of radio contact with Tiangong-1 in 2016 and due to the low orbital height, it is now inevitable that the Chinese space station will...
Fraunhofer Institute for Organic Electronics, Electron Beam and Plasma Technology FEP, provider of research and development services for OLED lighting solutions, announces the founding of the “OLED Licht Forum” and presents latest OLED design and lighting solutions during light+building, from March 18th – 23rd, 2018 in Frankfurt a.M./Germany, at booth no. F91 in Hall 4.0.
They are united in their passion for OLED (organic light emitting diodes) lighting with all of its unique facets and application possibilities. Thus experts in...
A new scenario seeking to explain how Mars' putative oceans came and went over the last 4 billion years implies that the oceans formed several hundred million...
For the first time, an interdisciplinary team from the University of Basel has succeeded in integrating artificial organelles into the cells of live zebrafish embryos. This innovative approach using artificial organelles as cellular implants offers new potential in treating a range of diseases, as the authors report in an article published in Nature Communications.
In the cells of higher organisms, organelles such as the nucleus or mitochondria perform a range of complex functions necessary for life. In the networks of...
19.03.2018 | Event News
16.03.2018 | Event News
13.03.2018 | Event News
22.03.2018 | Trade Fair News
22.03.2018 | Earth Sciences
22.03.2018 | Earth Sciences