Diagnosis & assessment of Alzheimer's Disease: Brief summaries of research reports

Diagnosis & assessment

Dementia often undiagnosed

Life expectancy following diagnosis of Alzheimer’s depends on age at diagnosis

July 2004

Dementia often undiagnosed

A study involving 553 patients of 34 primary care physicians affiliated with three Portland-area managed health care plans has confirmed previous research finding that many older patients showing signs of dementia are not being diagnosed. The study found that only 18% of mildly impaired patients and 34.8% of moderately-to-severely impaired patients were clinically evaluated for dementia, and that none of the mildly impaired patients and just 4.3% of the more severely impaired patients were offered dementia medication.
The study was published in the June issue of the Journal of Gerontology: Medical Sciences.
http://www.eurekalert.org/pub_releases/2004-07/ohs-sdo071504.htm

November 2002

Life expectancy following diagnosis of Alzheimer’s depends on age at diagnosis

A new study reveals that the life span of people with Alzheimer's disease depends greatly on the age of the person when Alzheimer's disease is diagnosed. The study indicates that the median survival of patients with Alzheimer's disease could range from 8.3 years for those diagnosed at age 65 to 3.4 years for those diagnosed at age 90. There were no significant differences between men and women. The average length of time between the onset of symptoms and the diagnosis of Alzheimer's was 2.8 years.
The findings are published in the November 18 edition of Archives of Neurology. Full reference
http://www.eurekalert.org/pub_releases/2002-11/jhub-lef111502.htm

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New tests

Computers better at diagnosing Alzheimer's

Portable device quickly detects early Alzheimer's

New diagnostic criteria for Alzheimer's disease

Protein 'fingerprint' in spinal fluid could spot Alzheimer's disease early

New reliable test for Alzheimer's

New diagnostic marker for Alzheimer's disease

A new portable device might be able to screen for Alzheimer's

New home-safety assessment scale for people with dementia living at home

Diagnosing Alzheimer's

New guidelines for diagnosis and treatment of Alzheimer's

February 2008

Computers better at diagnosing Alzheimer's

A new method has been developed that allows a standard computer to spot the differences between brain scans from patients with proven Alzheimer’s disease and people with no signs of the disease at all. The accuracy is better than the 86% correct diagnostic rate of best clinical practice. The method was also better at distinguishing Alzheimer’s from fronto-temporal dementia. The findings may help ensure that patients are diagnosed earlier, increasing treatment options.
The research was published in the March issue of Brain. Full reference
http://www.eurekalert.org/pub_releases/2008-02/wt-ccb022108.php

January 2008

Portable device quickly detects early Alzheimer's

A new device may allow patients to take a brief, inexpensive test that could be administered as part of a routine yearly checkup at a doctor’s office to detect mild cognitive impairment (MCI) — often the earliest stage of Alzheimer’s. The device, called DETECT, takes about ten minutes to run through a battery of visual and auditory stimuli such as pictures and words that assess cognitive abilities relative to age, gauging reaction time and memory capabilities. Its software can track cognitive capabilities year to year during annual appointments. Moreover, because the device blocks outside sound and light from the patient’s environment, it can be administered in virtually any setting, providing more consistent results. Preliminary analysis gives the test similar accuracy to the 90-minute “Gold Standard” pen and paper test. The device is expected to be commercialized later this year.
http://www.eurekalert.org/pub_releases/2008-01/giot-pdq011608.php

July 2007

New diagnostic criteria for Alzheimer's disease

An international group of Alzheimer’s disease (AD) experts have proposed new diagnostic criteria for Alzheimer’s. The existing criteria were published in 1984. To meet the new criteria for probable AD, patients must show progressive memory loss over more than six months, plus at least one or more of the supportive biomarker criteria. These include: atrophy in a particular part of the brain shown by MRI, abnormal biomarker proteins in the cerebrospinal fluid, a specific pattern on PET of the brain, and a genetic mutation for AD within the immediate family.
The proposal was published early Online and in the August edition of The Lancet Neurology. Full reference
http://www.eurekalert.org/pub_releases/2007-07/l-ndc070607.php

December 2006

Protein 'fingerprint' in spinal fluid could spot Alzheimer's disease early

In a pilot study, a panel of 23 protein biomarkers in cerebrospinal fluid has been found to be over 90% sensitive in identifying people with Alzheimer's disease.
The research was published online December 13 in Annals of Neurology. Full reference
http://www.eurekalert.org/pub_releases/2006-12/cuns-pi120706.htm

May2004

New reliable test for Alzheimer's

A new test for Alzheimer’s promises a reliable means of diagnosing Alzheimer’s in a living patient. Combined with clinical assessment, testing blood flow in a specific region of the brain may boost the degree of diagnostic certainty in difficult cases from 90% to almost 100%. The test involves use of single-photon emission computed tomography (SPECT) — a radioisotope test that produces a three-dimensional picture of the amount of blood flowing in certain regions of the brain — to identify a characteristic sign of Alzheimer's disease (reduced blood flow in the posterior cingulate cortex) and distinguish it from a group of illnesses known as frontotemporal diseases, which comprise the second-leading cause of dementia in the elderly. The test did fail to identify Alzheimer’s patients with an atypical form of Alzheimer’s known as tangle-predominant AD. This form of Alzheimer’s also appears to be resistant to drugs currently used to help treat Alzheimer’s. Evidence of shrinkage in brain structures such as the hippocampus and parietal cortex is also central to diagnosing Alzheimer's. This atrophy can be seen on a standard MRI.
The study appeared in the May edition of the Journal of Nuclear Medicine. Full reference http://www.eurekalert.org/pub_releases/2004-05/uots-rin050404.htm
http://www.eurekalert.org/pub_releases/2004-05/sonm-sis050504.htm

June 2003

New diagnostic marker for Alzheimer's disease

A mouse study has unexpectedly revealed that a protein that senses changes in calcium levels can be used to estimate the extent of cognitive deficits caused by toxic amyloid peptides found in Alzheimer brains. The discovery came about when researchers found that those mice with learning and memory deficits had not only the expected high level of amyloid peptides in their brains, but also had very low levels of a protein called calbindin that binds calcium and regulates functions in granule cells, located in the dentate gyrus (a region that plays an important role in memory formation). Examination of autopsy brain tissue from Alzheimer sufferers has confirmed this finding. It is hoped that this will prove a valuable diagnostic marker.
The findings were reported in the Proceedings of the National Academy of Sciences. Full reference
http://www.eurekalert.org/pub_releases/2003-07/uoc--bcs071003.htm

September 2001

A new portable device might be able to screen for Alzheimer's

NeuroGraph™, a portable device that provides an almost instantaneous reading of brain activity and can swiftly detect differences from the norm, offers enormous commercial potential as a screening device for Alzheimer’s disease. It might also be useful in pharmaceutical trials, to test the efficacy of new drugs on brain activity against drugs already on the market.
http://www.eurekalert.org/pub_releases/2001-09/oonr-da091901.htm

New home-safety assessment scale for people with dementia living at home

A pan-Canadian team of researchers designed, tested and validated the first "Home-safety Assessment Scale for People with Dementia Living at Home" (S.A.S.). The SAS has been tested and validated among 175 patients in English and French, in both urban and rural areas. "Thanks to the SAS, physicians, nurses, family helpers, social workers, physiotherapists and occupational therapists can now evaluate in a few minutes the risks of accidents in any particular home."
http://www.eurekalert.org/pub_releases/2001-09/mu-nha091401.htm

July 2001

Diagnosing Alzheimer's

It is not always easy for doctors to know whether a patient is suffering from Alzheimer's disease or some other form of dementia. A new study suggests tracking a patient's circadian rhythm (the daily cycle of body temperature change and activity) may lead not only to better diagnosis but also to better therapy for the devastating sleep disturbances that often accompany dementia. The study looked at the circadian rhythms of 38 dementia patients over six years. Some had Alzheimer's; others had what is known as fronto-temporal degeneration. Patients with Alzheimer's reached their temperature peak much later in the day than healthy people. People with fronto-temporal dementia had a normal temperature rhythm, but their activity levels peaked much earlier compared with levels of healthy people. And while people with fronto-temporal degeneration did have restful periods, these were much rarer with Alzheimer's. Their work, the researchers said, may help doctors who have tried to treat insomnia in dementia patients with melatonin and light therapy, in an effort to "reset" their biological clocks.
The study appeared in The Archives of General Psychiatry.
http://www.nytimes.com/2001/04/17/health/17VITA-5.html

May 2001

New guidelines for diagnosis and treatment of Alzheimer's

Experts reviewed more than a thousand studies to develop new guidelines for physicians for diagnosis and treatment of Alzheimer's. The recommendations include topics ranging from how to recognize early signs of Alzheimer's, how to diagnose, when medication is most effective and what types of support can improve the quality of life for patients and caregivers.
"It's important to remember there are choices available that can make a difference in your life or the life of your husband, grandmother, neighbor or anyone you care about who has Alzheimer's disease," said neurologist Steven DeKosky, MD, co-author of the guidelines. Early diagnosis is important because research shows current medication and care options are most effective in people with mild to moderate Alzheimer's disease. While Alzheimer's disease has no cure, medication can improve quality of life and cognitive functions–including memory, thought and reasoning– particularly among people who are mildly to moderately affected. Regular routines and activities such as mild exercise or walking can help with behavioral symptoms. In addition, education and support for caregivers can improve the well-being of both the person with Alzheimer's disease and the caregiver.
While the comprehensive guidelines were developed for physician use, a summary is available to help patients and their families better understand the options to discuss with their doctor.
The guidelines are published in the May 8 issue of Neurology, the scientific journal of the American Academy of Neurology, and online at www.aan.com.
http://www.eurekalert.org/pub_releases/2001-05/AAoN-Ngee-0605101.htm

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Scans

Study validates Pittsburgh Compound-B in identifying Alzheimer's disease toxins

Brain scans show early Alzheimer's disease in people with memory problems

Compound shows promise for early detection of Alzheimer's disease

Non-invasive MRI technique distinguishes between Alzheimer's and frontotemporal dementia

New computer program may enable early prediction of Alzheimer's risk

Expert system gives non-experts diagnostic accuracy of Alzheimer's disease from PET scans

Pet scans detect brain differences in people at risk for Alzheimer's

Rate of brain volume loss predicts dementia

New PET technique improves accuracy of early diagnosis of Alzheimer's

New technique allows sight of amyloid plaque in living brains

Hippocampal damage seen in those with alcoholic memory disorder and those with Alzheimer's

Imaging techniques help distinguish between Alzheimer's and vascular dementia

Activity in the mediotemporal lobe lower in elderly with poor memory

PET scans can help early diagnosis of Alzheimer's

Value of PET scans in diagnosing Alzheimer’s

MRI brain scan may detect Alzheimer's disease decades before first symptoms

Brain scans predict cognitive impairment

March 2008

Study validates Pittsburgh Compound-B in identifying Alzheimer's disease toxins

Previous research demonstrating that Pittsburgh Compound-B (PiB) binds to beta-amyloid deposits has involved only the autopsied brains of patients afflicted with Alzheimer’s. A new study correlated PiB-identified beta-amyloid deposits in a living patient with post-mortem autopsy results 10 months later, confirming that PiB allows accurate assessment of the amount of beta-amyloid plaques in brains of people afflicted with Alzheimer’s. A further study of the autopsied brains of 27 other patients with confirmed Alzheimer’s confirmed that PiB binds almost exclusively to beta-amyloid.
The findings were reported online March 12 in Brain. Full reference
Full text at http://brain.oxfordjournals.org/cgi/content/abstract/awn016v1
http://www.eurekalert.org/pub_releases/2008-03/uops-svp032608.php

May 2007

Brain scans show early Alzheimer's disease in people with memory problems

PET scans performed on the brains of 13 elderly men and women with mild cognitive impairment (MCI) and 14 elderly people without memory problems found that those with MCI had as much as 39% more PIB uptake in some parts of the brain than people without MCI, and about half of the MCI patients had PIB uptake in the Alzheimer's disease range. MCI subjects with at least one APOE 4 allele tended to have higher PIB uptake than MCI subjects without APOE 4. PIB is an imaging agent that allows amyloid plaque to be seen and measured.
The study was published in the May 8 issue of Neurology. Full reference
http://www.eurekalert.org/pub_releases/2007-05/aaon-bs050107.htm

December 2006

Compound shows promise for early detection of Alzheimer's disease

A new molecular marker called FDDNP has been found to track the progression of Alzheimer’s in PET scans more effectively than other markers, giving hope of earlier, more accurate diagnosis of the disease.
The study was published in the December 21 issue of the New England Journal of Medicine. Full reference
http://www.eurekalert.org/pub_releases/2006-12/nioa-nic121906.htm
http://www.eurekalert.org/pub_releases/2006-12/uoc--nit121506.htm

June 2005

Non-invasive MRI technique distinguishes between Alzheimer's and frontotemporal dementia

A new study has found that a non-invasive imaging technique called arterial spin labeling is just as accurate and much faster and cheaper compared to invasive scanning techniques in distinguishing Alzheimer's disease from frontotemporal dementia (FTD). Frontotemporal dementia is the second-most common dementia after Alzheimer's disease. The present study aimed simply at differentiating the two types of dementia; further research needs to be done to confirm that the technique can be used to diagnose an individual patient.
The results were presented at the first International Conference on Prevention of Dementia, held June 18-21 in Washington, D.C.
http://www.eurekalert.org/pub_releases/2005-06/uoc--nmt061605.htm

New computer program may enable early prediction of Alzheimer's risk

Researchers have developed a brain scan-based computer program that quickly and accurately measures metabolic activity in the hippocampus, a key brain region that shrinks with the development of Alzheimer’s. The study followed 53 normal subjects aged 54 to 80 for at least 9 years and in some cases for as long as 24 years, and found that hippocampal glucose metabolism was significantly reduced on the first scan of those 25 individuals who would later experience cognitive decline related to either mild cognitive impairment or to Alzheimer's. The findings bring hope of being able to predict who will develop Alzheimer’s at least 9 years ahead of symptoms.
The technical details of the program were published in the June issue of Neurology. Full reference
http://www.eurekalert.org/pub_releases/2005-06/nyum-ncp061505.htm

Expert system gives non-experts diagnostic accuracy of Alzheimer's disease from PET scans

A computer program has been developed that enhances the diagnostic accuracy of PET scans with Alzheimer's patients. A PET scan is a very reliable noninvasive test, but only in the hands of an experienced investigator. The new program enables even inexperienced doctors to diagnose reliably, hopefully enabling diagnosis to occur earlier.
The findings were presented at the Society of Nuclear Medicine's 52nd Annual Meeting in Toronto. Reference
http://www.eurekalert.org/pub_releases/2005-06/sonm-esd061605.htm

November 2004

Pet scans detect brain differences in people at risk for Alzheimer's

Brain imaging of 32 participants, mostly in their 60s and 70s, has found clear differences in brain function between healthy people who carry a genetic risk factor for Alzheimer's disease and those who lack the factor. More research is needed before it's known for certain if the difference is an early sign of Alzheimer's.
The study appeared in the Nov.-Dec. 2004 issue of the American Journal of Geriatric Psychiatry. Full reference
http://www.eurekalert.org/pub_releases/2004-11/cuco-psd111904.htm

April 2004

Rate of brain volume loss predicts dementia

A new study has found that rates of total brain volume loss may help identify patients with mild cognitive impairment who are at high risk of developing dementia. The study followed 55 people over 14 years, and found that loss of volume in the hippocampus predicted which mildly cognitively impaired individuals would stay stable and which would decline to Alzheimer's with 70% accuracy, while the rate of total brain volume loss was 62% accurate in predicting cognitive outcome. Combining both variables produced the strongest model: 75% accuracy. The discovery could help doctors plan early treatment strategies and prevention studies.
The study was presented at the 56th annual meeting of the American Academy of Neurology in San Francisco.
http://www.eurekalert.org/pub_releases/2004-04/ohs-osr042804.htm

March 2004

New PET technique improves accuracy of early diagnosis of Alzheimer's

A new study identifies a new Positron Emission Tomography (PET) scanning technique that may increase the already high accuracy of PET in diagnosing Alzheimer’s at a very early stage. Altered brain connections between the entorhinal cortex and both hemispheres of the brain can be clearly identified with 18F-FDG PET. The entorhinal cortex is a critical site for learning and memory. It now appears that most of its connections to the neocortex in both hemispheres are destroyed at a very early stage of Alzheimer’s.
The study appeared in the March issue of The Journal of Nuclear Medicine. Full reference
http://www.eurekalert.org/pub_releases/2004-03/sonm-nss031104.htm

January 2004

New technique allows sight of amyloid plaque in living brains

The first human study has now been completed of a compound that, through PET scanning, enables researchers to see the amyloid plaque deposits in the brains of Alzheimer’s sufferers. The compound has been dubbed Pittsburgh Compound B (PIB), and should be a very useful new tool in Alzheimer’s research.
The study was reported in the March issue of Annals of Neurology. Full reference
http://www.eurekalert.org/pub_releases/2004-01/uopm-uop012104.htm

December 2003

Hippocampal damage seen in those with alcoholic memory disorder and those with Alzheimer's

A comparison between the brains of five men with alcoholic Korsakoff's syndrome and the brains of men with Alzheimer's disease as well as the brains of healthy men, found that the brains of all Korsakoff's patients and Alzheimer's patients were comparable in significant volume loss in the hippocampus. Greater hippocampal damage (for Korsakoff's patients) and smaller hippocampal size (for Alzheimer’s) was correlated with poorer memory performance. It is suggested that, although there are of course a number of differences between these disorders, the nature of the memory impairment may be the same. Awareness of the similarities may help detection of both disorders.
The study was published in the December 23 issue of Neurology. Full reference
http://www.eurekalert.org/pub_releases/2003-12/aaon-seu121503.htm

July 2003

Imaging techniques help distinguish between Alzheimer's and vascular dementia

A combination of magnetic resonance imaging (MRI) and MR spectroscopy has enabled researchers to differentiate between Alzheimer’s and dementia caused by poor blood flow (vascular dementia). Comparison of the brains of those with Alzheimer’s, those who had suffered subcortical ischemic vascular dementia (SIVD), and those belonging to cognitively normal older adults, also found significant differences in the chemical signature of various brain regions, leading researchers to suggest that in patients with SIVD, there may only be neuronal dysfunction rather than neuronal loss, offering hope for recovery of neuronal function in these areas. More research is needed to confirm these results.
The study appeared in the August 12 issue of Neurology. Full reference

March 2003

Activity in the mediotemporal lobe lower in elderly with poor memory

An imaging study has revealed that, although there is no difference on standard MRI scans,scans showing the amount of oxygen (and thus activity) find that elderly persons with a poor memory have less activity in the mediotemporal lobe when storing new information than elderly persons with a normally functioning memory.This more sensitive scan may help early diagnosis of Alzheimer's. You can see an image of the brain scans at www.nwo.nl/news.
The research was done as part of a doctoral thesis by Dr Sander Daselaar.
http://www.eurekalert.org/pub_releases/2003-03/nofs-svp032103.htm
http://www.nwo.nl/NWOHome.nsf/pages/NWOP_5KRH7V?OpenDocument&g=NWO&n=ACPP_4WMESE&rc=1

November 2002

PET scans can help early diagnosis of Alzheimer's

Early diagnosis of Alzheimer’s is becoming more and more important, with the arrival of drugs and therapies which can help slow the progression of the disease, if caught early. A new study reveals that PET scans may be able to identify Alzheimer’s, and distinguish it from other dementias.
Initial results were presented recently at the International Conference on Alzheimer's Disease and Related Disorders.
http://www.eurekalert.org/pub_releases/2002-11/uomh-sit110102.htm

October 2002

Value of PET scans in diagnosing Alzheimer’s

A new study has measured the advantage of early diagnosis of Alzheimer’s using PET scanning. The study compared the use of two strategies for diagnosing Alzheimer's: clinical evaluation using the American Academy of Neurology (AAN) 2001 recommendations, and the same with the addition of a PET scan. They concluded that, although both approaches accurately diagnosed most Alzheimer's patients, the appropriate use of PET reduced erroneous diagnoses by half. A review of the literature suggested conventional methods would falsely attribute symptoms to early Alzheimer's in 23 cases out of 100, and overlook eight cases. Analysis suggested that incorporating PET scans would have prevented 11 of the 23 false positives and five of the eight false negatives. The researchers estimated that PET could cut unnecessary drug therapy by half (48%) and reduce months in a nursing home by 62%.
The study was reported in the Nov/Dec issue of Molecular Imaging and Biology. Full reference
http://www.eurekalert.org/pub_releases/2002-10/uoc--uss100402.htm

May 2002

MRI brain scan may detect Alzheimer's disease decades before first symptoms

MRI scans of the brain may detect Alzheimer’s disease decades before the first clinical signs of dementia occur, according to a study revealing that shrinkage of the hippocampus occurs very early in the disease process.
The report appeared in the May 28 issue of Neurology. Full reference
http://www.eurekalert.org/pub_releases/2002-05/uosf-mbs052302.htm

September 2001

Brain scans predict cognitive impairment

A three-year study of 48 healthy people from 60 to 80 years old, by New York University School of Medicine researchers, predicted which healthy elderly men and women would develop memory impairment based on scans of their brains. At the beginning of the study, everyone scored within the normal range on a battery of tests typically used to detect early loss of memory and other mental skills. However, PET scans revealed a reduction in glucose metabolism in an area of the brain called the entorhinal cortex among 12 people. Three years later, 11 of these people had experienced mild cognitive impairment and one had developed Alzheimer's disease. "Our work extends the use of PET scanning to identifying in normal aging subjects the earliest metabolic abnormalities that may lead to the memory losses referred to as mild cognitive impairment (MCI). The diagnosis of MCI carries a high risk for future Alzheimer's disease."
The study is published in the September 11 issue of The Proceedings of the National Academy of Sciences.
http://www.eurekalert.org/pub_releases/2001-09/nyum-bps090701.htm

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