A company has begun selling the first blood test to help diagnose Alzheimer’s disease. This is a leap in the field, and it can make it easier for people to know if they have dementia. This also arouses people’s attention to the accuracy and impact of this life-changing news.
Independent experts are opposed to this because the key test results have not yet been released and the test has not yet been approved by the US Food and Drug Administration-for sale under the more general rules of commercial laboratories. But they agree that simple tests that can be performed in a doctor̵
This may have saved Tammy Maida from a decade of futile travel by doctors who attributed her symptoms to depression, anxiety, or menopause, and then a $5,000 brain scan performed last year ended up Shows that she suffers from Alzheimer’s disease.
“I have an answer now,” said the 63-year-old former nurse from San Jose, California.
She said that if a blood test can be performed, “I might be afraid of the result” but would “jump on this” to find it.
There are more than 5 million people in the United States, and millions of people around the world suffer from Alzheimer’s, which is the most common form of dementia. To be diagnosed with this disease, people must have symptoms such as memory loss and evidence of a buildup of a protein called beta-amyloid in the brain.
The best way to measure protein now is an expensive PET brain scan, which is usually not covered by insurance. This means that most people get nothing and just want to know if their problem is caused by normal aging, Alzheimer’s disease or other reasons.
The blood test of C2N Diagnostics in St. Louis aims to fill this gap. The company’s founders include Drs. David Holtzman and Randall Bateman of Washington University School of Medicine led the research that led to the trial, and the patent was included in the patents granted by St. Louis University to C2N licenses .
The test is not suitable for general screening or asymptomatic people, but for people 60 years and older who have thinking problems and are being evaluated for Alzheimer’s disease. It is not included in insurance or medical insurance; the company charges $1,250 and offers discounts based on income. Only doctors can order tests, and test results will appear within 10 days. It is available in all countries except the United States (except for a few states) and has just been sold in Europe.
It can measure two types of amyloid particles and various forms of proteins, which can reveal whether someone has genes that increase the risk of the disease. Combining these factors into a formula that includes age and scoring the patient indicates that the likelihood of amyloid accumulation in the brain is low, medium or high.
Bateman said that if the test puts them in the lower category, then “a strong reason to look for other things besides Alzheimer’s disease.”
Holtzman said: “There are thousands of things that can cause someone’s cognitive impairment,” from vitamin deficiencies to medications.
He said: “I don’t think this is any different from the test we are doing now,” except that it comes from a blood test rather than a brain scan. “And it’s not 100% accurate.”
Is it accurate?
Although doctors have released amyloid studies that led to the test, the company has not released any data on the accuracy of the test. The company’s promotional materials cited the results of comparing test results with PET brain scans (the current gold standard). The study compared 686 people aged 60-91 with cognitive impairment or dementia. .
The company’s chief executive, Dr. Joel Braunstein, said that if a PET scan shows amyloid buildup, the blood test is likely to happen in 92% of cases, and 8% are missing.
If the PET scan is negative, the blood test can rule out amyloid accumulation 77% of the time. Braunstein said the other 23% had a positive result, but that does not necessarily mean that the blood test was incorrect. Published research suggests that it may detect amyloid accumulation before scanning.
Braunstein said the company will seek FDA approval and the agency has assigned a name that can speed up the review process. He said the results of the study will be published, and he defended the decision to start selling the test now.
He asked: “When the technology may have a significant impact on patient care, should we keep it?”
Dr. Eliezer Masliah, head of neuroscience at the National Institute of Aging, said the government funded some work that led to the test and other types of blood tests.
Speaking of the company’s proposition, he said: “I will be cautious about explaining any of these things.” “We are very encouraged, we are very interested, we are funding this work, but we want to see results. “
Heather Snyder of the Alzheimer’s Association said the test would not be approved without FDA approval. The test also needs to be studied in a larger and diverse population.
She said: “It is not yet clear whether the results are accurate or generalizable.”