The blood test for Alzheimer's is now being used in hospitals.
The test has been tested in Catalonia, Sweden and Italy and would reduce diagnostic costs by at least 60%.
BarcelonaThe future of early detection of Alzheimer's, the world's leading neurodegenerative disease, lies in blood tests. The international scientific community has long since made this a reality by proposing, designing, and marketing several examples of biomarker tests—any biological molecule that can be identified and quantified—in blood. Now, their arrival in hospitals is closer than ever. Five hospitals and university centers in Barcelona, Sweden, and Italy conducted a study with more than 1,700 people with early symptoms of the disease, validating the usefulness of a test for highly accurate detection of the disease; a test that is already beginning to be used in centers such as Hospital del Mar.
The magazine Nature Medicine has published an article this Wednesday with the results of this tool made in Europe (but designed by a Japanese company), which states that "it can be useful and applicable in routine medical practice." It was led by researchers from the Barcelona Beta Brain Research Center (BBRC), the Pasqual Maragall Foundation research center, and the Hospital del Mar Research Institute. The hospital and university of Brescia (Italy) and the universities of Gothenburg and Lund (Sweden) also participated in the study, validating its ability to predict the risk of Alzheimer's in people with symptoms of cognitive decline based on blood tests. The test is around 90% effective, similar to the standard test (lumbar puncture), and its promoters claim that it can significantly reduce the costs associated with diagnosis: at least 60% (and up to 81%) compared to current tests.
In this case, the experts used a biomarker called phospho-tau217, which is easily detectable in blood. This test can also be performed in any clinical laboratory; that is, highly sophisticated systems or those different from those used in clinics are not required. This reduces costs, and, together with its large-scale applicability, this new tool "can contribute to democratizing access to early diagnosis and, in the medium term, improve the clinical approach to the disease," its creators insist.
The test, designed by Fujirebio, is called Lumipulse p-tau217 and allows for establishing levels at which it can be determined that a person will develop the disease or is at risk. "This may allow us to determine which people should undergo other tests, such as a lumbar puncture or positron emission tomography (PET) with beta-amyloid, and which ones no longer require further testing, as it allows for very precise early detection of Alzheimer's," explains doctor Marco Suárez-Calvet. The authors admit that further studies will be needed to implement it in clinical practice, but emphasize that the study combined populations from different countries, allowing for conclusions to be drawn that can be extrapolated to several groups, which were followed up in primary care and hospitals.
Useful at younger ages
According to the neurologist, the test establishes two cutoff points (a range of values) by which the patient's symptoms can be considered to be caused by Alzheimer's. It also determines whether the disease can be ruled out or whether further testing is necessary to determine this. Thus, those who present a biomarker level between these two values are indicated for further diagnostic testing.
The researchers have taken into account both the patients' possible underlying diseases (diabetes or kidney function, for example) and their age, and have concluded that the test is more reliable the younger the user is (under 80 years old). "These results should always be interpreted by a neurologist or other specialized healthcare professional, after an appropriate neurological assessment. Never as a stand-alone test," insists Suárez-Calvet.
"This is a very well-conducted study of high scientific quality," says Eloy Rodríguez Rodríguez, head of the Neurology Department at the Marqués de Valdecilla University Hospital-IDIVAL, in a statement to SMC. "The results point to the clinical utility of this marker and the potential for its use to extend from specialized clinics, where they are just beginning to be used and are already recommended by the Dementia Group of the Spanish Society of Neurology (SEN), to less specialized clinics," he adds.
A new study suggests that the risk of Alzheimer's is higher if the father has it. Published in the journal Neurology of the American Academy of Neurology, the article doesn't prove the link, but suggests that if a father has Alzheimer's, his offspring may have a higher concentration of tau protein in the brain, a sign of dementia, especially if the children are girls.
The study was conducted using data from 243 people with a family history of Alzheimer's but no symptoms. Seven years later, 71 of them presented mild cognitive impairment, the majority of them women. Furthermore, their parents had suffered from Alzheimer's. The female participants also had a stronger accumulation of tau protein in their brains.
"Better understanding these vulnerabilities could help us design tailored interventions," says study author Sylvia Villeneuve of McGill University in Montreal, Canada.
