According to Ynet news reports, A new blood test that combines two Alzheimer’s biomarkers shows a 90% accuracy in diagnosing the disease, outperforming neurologists and primary care physicians. Researchers noted that further studies are required to confirm its effectiveness.
In comparisons with neurologists and primary care doctors, who diagnosed Alzheimer’s accurately in only 73% and 61% of cases respectively, the blood test proved superior. This study, involving 1,213 participants with an average age of 74, was conducted in Sweden and involved cognitive assessments in both primary care and specialist clinics.
The blood test integrates two key biomarkers for early Alzheimer’s detection: p-tau217 and the amyloid beta 42/40 ratio. The amyloid beta 42/40 ratio helps detect amyloid beta proteins in the brain, indicating Alzheimer’s risk, while p-tau217 is used to diagnose cognitive impairment and early-stage Alzheimer’s. According to Dr. Sebastian Palmqvist, a senior neurologist at Lund University in Sweden, p-tau217 levels are significantly elevated in Alzheimer’s patients, more than eight times higher than in those without the disease.
A previous study in January found that the p-tau217 test is about 96% accurate in detecting elevated amyloid beta levels and 97% accurate for tau protein. The new study’s combined approach, using the p-tau217 test and the amyloid beta 42/40 ratio, enhances diagnostic accuracy for Alzheimer’s.
Although the test is not yet available for widespread use and requires further validation, researchers believe it has the potential to transform Alzheimer’s diagnosis and treatment. Current diagnostic methods, including interviews, short cognitive tests, and CT scans, are often inaccurate and may lead to misdiagnosis.
Experts also pointed out that new dementia medications, like Lecanemab and Donanemab, target amyloid beta but are less effective against advanced tau tangles, a core aspect of Alzheimer’s pathology. Accurate blood tests could significantly reduce diagnosis wait times, potentially from six years to between six and 13 months, according to projections based on the U.S. aging population.
In the meantime, a similar blood test, AD-Detect, has been available in Israel since March. Developed by Quest Diagnostics and exclusively represented in Israel by Medical Link, AD-Detect identifies high amyloid beta concentrations, indicating Alzheimer’s. It has shown 89% accuracy in clinical trials. This test, along with the p-tau 181 test and the AD-Detect ApoE genetic test, forms a comprehensive diagnostic package.
The AD-Detect ApoE test assesses genetic risk for amyloid beta accumulation and Alzheimer’s, specifically identifying the E4 allele variant in the ApoE gene. This test is nearly 100% accurate and helps match treatments with anti-amyloid drugs.
The tests are available in Israel with prices starting at 3,450 shekels for the amyloid test, 4,850 shekels when including the p-tau test, and 5,850 shekels for the comprehensive test. Most private health insurance plans cover the costs. Blood samples are collected nationwide, with results typically available within two weeks.
