New blood test method to warn the elderly, the accuracy rate of dementia reaches 94%:
The new study found a simple blood test method that can make an early warning before the elderly dementia symptoms have not appeared, and the best PET at present. The accuracy of the scan results has reached 94%. More importantly, this screening method will significantly advance the clinical research rate of elderly dementia drugs.
- 20 years before the onset of symptoms
Old-age dementia (also known as Alzheimer’s disease ) has been documented for more than a hundred years, and there are no drugs that can effectively delay or control the deterioration of memory, and there is no cure for drugs. Recently, some new drugs that were originally optimistic about the industry are disappointing in clinical performance.
One difficulty in developing drugs to treat the disease is that when the symptoms are manifested, damage to the brain’s neurons has been caused, almost irreversible. Therefore, many researchers now focus on how to predict this disease early.
In fact, in the 20 years before the onset of symptoms of memory loss in the elderly, dementia has begun to accumulate in the brain. Early detection will greatly reduce the chance of disease progression.
- Blood detection mechanism
According to the investigator, this method identifies patients as “amyloid-positive” or “amylase-negative” by detecting the ratio of two amyloid proteins, amyloid 42 and amyloid 40, in the blood. If the accumulation of amyloid in the brain increases, the researchers found that the ratio of these two proteins will decrease. The earliest version of this method appeared two years ago, which improves the accuracy of the test.
The study involved 158 adults over 50 years of age. Except for 10 people, other people’s cognition is normal. Everyone had a blood test and a PET scan of the brain. The results showed that 88% of the blood test results were consistent with the PET scan results.
As a means of clinical testing, such accuracy is not enough. The researchers combined several other factors.
The first is age. According to the study, the chance of suffering from dementia in the elderly after the age of 65 doubles every five years. In addition, the APOE4 variant gene also increases the risk of disease by 3 to 5 times. Finally, gender is also very relevant, and two-thirds of the patients are women.
Randall J. Bateman, one of the main investigators at the University of Washington School of Medicine, said that after combining the first two factors, the accuracy of the test evaluation increased to 94%, while the gender factor had no significant effect on accuracy.
The blood test successfully intercepted the “fish that leaked the net”
What is even more exciting for researchers is that this assay is more accurate than PET brain scans at the beginning of the accumulation of amyloid in the brain. PET brain scans are currently considered the “gold standard” for the diagnosis of dementia in the elderly.
In this study, some patients with positive initial blood tests were negative for PET scans, so researchers began to think that blood tests were inaccurate. However, after the average of four years, the brain was detected again on the subject, and a positive result was obtained. This means that blood tests alert the disease earlier than brain scan detection.
The study also showed that blood tests were performed first, and if a positive result was obtained and a PET brain examination was performed, the number of appointments for PET examinations would be reduced by nearly two-thirds.
Blood tests can greatly speed up drug development
This blood test can be put into use at the clinic within a few years. If an effective drug that delays the progression of the disease can be developed, the combination of the two will be more effective.
The blood test will be helpful for the latter study. The current clinical study of drugs for delaying dementia in the elderly is largely limited by the difficulty in finding subjects with some signs of aura in the brain but who have not yet developed symptoms. Blood testing is an effective way to find these objects.
Bateman said: “Now we use brain scans to screen clinical subjects, which is time-consuming and costly. Patients who are waiting to be examined are queued for several years. With blood tests, we can screen thousands of people in a month. This means that We will speed up the identification of patients involved in drug clinical trials and accelerate drug development.”
Be aware that PET inspections can cost up to $4,000 each time. In addition, a single hospital facility can only schedule a few PET exams per month. Because these facilities must first meet the patient’s reservation, and then accept the study-oriented appointment.
“If you want to screen the subjects involved in the clinical study, about 10,000 people will be scanned for 1,500 to 2,000 people,” Bateman said. “Reducing the number of PET tests will allow us to double the clinical budget within the same budget and time. Research. Not reluctant to spend $4,000 on a scan, we worry that millions of patients suffer from this disease, and we have no effective treatment. If we can speed up clinical trials, we will find treatment faster. Program.”