Detection Tools for Alzheimer

I posted earlier on the Behaviors of Alzheimer patients. Here is an article on the detection tools.

Early Detection Alzheimer’s Tests: What’s New

By Sarah Stevenson on January 26, 2013

Read about the growing arsenal of Alzheimer’s tests, from simple memory testing for mild cognitive impairment to brand-new brain imaging applications.

Photo credit: Akira Ohgaki

When it comes to diagnosing Alzheimer’s disease, the prevailing mantra is “the earlier the better.” The problem, of course, is that there are many potential causes for dementia, and by the time doctors are able to detect mental decline, Alzheimer’s has already begun to irreversibly damage the brain. Not only that, until recently it was only possible to confirm an Alzheimer’s diagnosis through posthumous brain examination.
Cutting-edge research in the field of Alzheimer’s testing promises to change the way we diagnose the disease, and that’s encouraging news. With a new battery of tests in the arsenal, doctors are hoping to begin pinpointing the warning signs of Alzheimer’s disease before patients start to show symptoms.

Common Tests for Alzheimer’s Focus on Symptoms and Risk Factors

If you’re worried about cognitive changes or memory loss in an elderly loved one, a good first step is an interview with your family doctor or general practitioner. He or she will probably ask a variety of questions about their memory difficulties as well as their general health, medical history, and whether or not anyone else in the family has ever been diagnosed with Alzheimer’s or other dementia.
If your loved one is determined to be at risk for Alzheimer’s, the doctor may refer you to a specialist for further testing—usually a psychiatrist and/or a neurologist. The specialist will look for particular patterns that tend to distinguish Alzheimer’s and dementia symptoms from other types of memory loss.
Standard tests include:

• Physical and neurological: Measures reflexes, balance, even vision and hearing (Mayo Clinic). Something as simple as looking at how a patient walks can point to problems with their cognitive faculties. Blood or urine tests may be suggested in order to rule out other possible causes of cognitive problems such as anemia or malnutrition.
• Cognitive: Measures the ability to solve simple problems as well as Long-term and short-term memory testing. The results may help a doctor determine if more testing is needed.
• Neuropsychological:  Time-intensive assessment of thinking and memory performed by a psychologist or psychiatrist, usually conducted if a physician thinks early-stage dementia is present.
  

The Latest News on Early Detection

Right now there is no single test that can indicate Alzheimer’s early enough for truly effective treatment. However, cutting-edge research is pointing to some promising avenues of detection in the area of biomarkers, which are biological indicators that reliably predict disease:

• Brain imaging as a way to look for brain changes caused by Alzheimer’s, such as shrinkage in brain volume, reductions in brain activity, or the presence of telltale beta-amyloid, would be useful markers for early diagnosis. Research suggests that brain imaging technologies such as MRI, CT, and PET scans may help doctors with early detection. There’s even a new PET scan test for amyloid plaques that uses a radioactive dye, or tracer, to show deposits of beta-amyloid.
• Cerebrospinal fluid (CSF) protein levels may show changes in the early stages of Alzheimer’s—researchers are still gathering information on this possibility, but the test would potentially be a simple spinal tap.
• Proteins in the blood or other areas of the body may provide helpful clues to early-stage Alzheimer’s. Scientists are investigating biomarkers in blood, urine, and even the lens of the eye.
• Genetic markers are genes that indicate increased risk for Alzheimer’s, and many of these genes have already been identified. There are even a few rare genes that directly cause Alzheimer’s. However, genetic testing is limited largely to the research setting.
  

A recent article on the use of PET scans to detect amyloid plaques emphasizes that brain imaging and other methods are just one tool used by doctors to diagnose Alzheimer’s–the presence of amyloid on its own does not necessarily mean Alzheimer’s disease. When properly used, the PET scan is the second step in a process that starts with full evaluation of the patient’s memory and cognitive difficulties. A dementia expert will then assess the need for brain imaging or further tests in those who show a specific pattern of symptoms. All of the available information, including PET scan results, will be used in diagnosis.

Should Mom Get Tested?

Many of these new tests are not yet covered by Medicare or other insurance, and they are not cheap—the PET scan for amyloid plaques, for instance, costs $3,250, according to CBS News. And genetic testing carries its own risks aside from the price tag—it’s possible that the presence of an Alzheimer’s gene could affect insurance eligibility, notes the Alzheimer’s Association.

Nevertheless, it’s likely that the next few years will continue to see major advances in early diagnosis and testing for Alzheimer’s disease, and that’s good news for families and caregivers concerned about the risk of dementia.
What’s your experience with Alzheimer’s testing? If you had the opportunity for genetic testing or other early tests to diagnose Alzheimer’s disease, would you take it? Let us know in the comments.

A response to this article from a reader is also very interesting.

Len Hudyma

Are your readers aware of this most recent discovery by a small Canadian company.

TORONTO, Ontario - November 21, 2012 - In response to interest from the drug development industry, Amorfix Life Sciences Ltd. announced today that it is offering the EP-AD assay service to customers and that a number of pharmaceutical companies are currently evaluating the test in several pilot studies.

Amorfix previously announced that the EP-AD test has shown a significant increase in aggregated Abeta levels in CSF samples from AD patients and patients with mild cognitive impairment (MCI) compared to age-matched control subjects. More recently, the Company announced that it has found a statistically significant correlation between aggregated Abeta levels and minimental state examination (MMSE) scores in normal aged individuals suggesting that the EP-AD test may be able to capture the transition from normal aging to MCI. In a study conducted by the Company, the ED-AD CSF test was more sensitive at identifying individuals with MCI (94% sensitivity) than current biomarkers (monomeric Abeta 42 and phospho-tau). The Amorfix diagnostic offers several distinct advantages over the other tests. It measures small aggregates of Abeta (called oligomers) which are thought to be responsible for the major part of Abeta toxicity, and are regarded as the most relevant molecule in disease pathogenesis. In addition, the ED-AD CSF test can identify early-stage patients before they progress into frank AD.

Alzheimers disease progresses through three defined phases: a stage characterized by amyloid buildup in the brain without any symptoms of the disease, MCI predominantly affecting memory function, and full-blown Alzheimers disease. Loss of memory is common in normal aging. Diagnostic tools are needed to differentiate between mere age related loss of memory and early onset of AD.

Len Hudyma
Edmonton Alberta Canada.

(Courtesy: aplaceformom.com)