Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Memory test and PET scans detect early signs of Alzheimer's

15.07.2009
A large study of patients with mild cognitive impairment revealed that results from cognitive tests and brain scans can work as an early warning system for the subsequent development of Alzheimer's disease.

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!
Further information:
http://www.berkeley.edu

More articles from Health and Medicine:

nachricht Team discovers how bacteria exploit a chink in the body's armor
20.01.2017 | University of Illinois at Urbana-Champaign

nachricht Rabies viruses reveal wiring in transparent brains
19.01.2017 | Rheinische Friedrich-Wilhelms-Universität Bonn

All articles from Health and Medicine >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Traffic jam in empty space

New success for Konstanz physicists in studying the quantum vacuum

An important step towards a completely new experimental access to quantum physics has been made at University of Konstanz. The team of scientists headed by...

Im Focus: How gut bacteria can make us ill

HZI researchers decipher infection mechanisms of Yersinia and immune responses of the host

Yersiniae cause severe intestinal infections. Studies using Yersinia pseudotuberculosis as a model organism aim to elucidate the infection mechanisms of these...

Im Focus: Interfacial Superconductivity: Magnetic and superconducting order revealed simultaneously

Researchers from the University of Hamburg in Germany, in collaboration with colleagues from the University of Aarhus in Denmark, have synthesized a new superconducting material by growing a few layers of an antiferromagnetic transition-metal chalcogenide on a bismuth-based topological insulator, both being non-superconducting materials.

While superconductivity and magnetism are generally believed to be mutually exclusive, surprisingly, in this new material, superconducting correlations...

Im Focus: Studying fundamental particles in materials

Laser-driving of semimetals allows creating novel quasiparticle states within condensed matter systems and switching between different states on ultrafast time scales

Studying properties of fundamental particles in condensed matter systems is a promising approach to quantum field theory. Quasiparticles offer the opportunity...

Im Focus: Designing Architecture with Solar Building Envelopes

Among the general public, solar thermal energy is currently associated with dark blue, rectangular collectors on building roofs. Technologies are needed for aesthetically high quality architecture which offer the architect more room for manoeuvre when it comes to low- and plus-energy buildings. With the “ArKol” project, researchers at Fraunhofer ISE together with partners are currently developing two façade collectors for solar thermal energy generation, which permit a high degree of design flexibility: a strip collector for opaque façade sections and a solar thermal blind for transparent sections. The current state of the two developments will be presented at the BAU 2017 trade fair.

As part of the “ArKol – development of architecturally highly integrated façade collectors with heat pipes” project, Fraunhofer ISE together with its partners...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Sustainable Water use in Agriculture in Eastern Europe and Central Asia

19.01.2017 | Event News

12V, 48V, high-voltage – trends in E/E automotive architecture

10.01.2017 | Event News

2nd Conference on Non-Textual Information on 10 and 11 May 2017 in Hannover

09.01.2017 | Event News

 
Latest News

Helmholtz International Fellow Award for Sarah Amalia Teichmann

20.01.2017 | Awards Funding

An innovative high-performance material: biofibers made from green lacewing silk

20.01.2017 | Materials Sciences

Ion treatments for cardiac arrhythmia — Non-invasive alternative to catheter-based surgery

20.01.2017 | Life Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>