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This Simple Blood Test Could Determine if You Have Dementia

Researchers have discovered levels of a protein called neurofilament light chain (NfL) in the blood.
FACT CHECKED BY Emilia Paluszek

What if you could just test your blood and determine if you have, or may get, dementia? Or Parkinson's? Or Down Syndrome? Researchers, in a new study just published in Nature Communications, say this may be possible. They studied levels of a protein called neurofilament light chain (NfL) in the blood, and found that they could be predictive of disease—even if the patient is showing no symptoms. The study's promise could have wide-ranging effects. Read on to find out if this test may be for you—and to ensure your health and the health of others, don't miss these Sure Signs You Have "Long" COVID and May Not Even Know It.

The Simple Blood Test May Be "Clinically Useful" in Identifying Diseases, Including Dementia

"We demonstrate that plasma NfL is clinically useful in identifying atypical parkinsonian disorders in patients with parkinsonism, dementia in individuals with Down syndrome, dementia among psychiatric disorders, and frontotemporal dementia in patients with cognitive impairment," say the authors, who were part-funded by the NIHR Maudsley Biomedical Research Centre.

"For the first time we have shown across a number of disorders that a single biomarker can indicate the presence of underlying neurodegeneration with excellent accuracy," said study author Dr Abdul Hye. "Though it is not specific for any one disorder, it could help in services such as memory clinics as a rapid screening tool to identify whether memory, thinking or psychiatric problems are a result of neurodegeneration."

"For neurodegenerative diseases like Alzheimer's, Parkinson's or motor neuron disease, a blood test to allow early diagnosis and help us monitor disease progression and response to treatment would be very helpful," said Co-author Professor Ammar Al-Chalabi from at King's College London and co-lead of the Psychosis and Neuropsychiatry research theme at the NIHR Maudsley BRC. "Neurofilament light chain is a promising biomarker that could speed diagnosis of neurodegenerative diseases and shorten clinical trials."

Those With Dementia Had Higher Levels Than Those That Did Not

For their research, the authors studied subjects from the King's College London, Lund University and Alzheimer's Disease Neuroimaging Initiative, including those with no symptoms. "This study shows that neurofilament light chain levels were particularly increased in adults with Down syndrome who have a genetic predisposition for Alzheimer's disease," said co-author Andre Strydom, Professor in Intellectual Disabilities at King's College London. "Furthermore, we showed that those individuals with a dementia diagnosis following onset of Alzheimer's disease had higher levels than those who did not. This suggests that the new marker could potentially be used to improve the diagnosis of Alzheimer's in people with Down syndrome, as well as to be used as biomarker to show whether treatments are effective or not. It is exciting that all that could be needed is a simple blood test, which is better tolerated in Down syndrome individuals than brain scans."

"In conclusion, in two large independent datasets, we have detailed the meaningful strengths and weaknesses of utilizing plasma NfL as a biomarker for neurodegeneration that could be useful in a primary care setting," they wrote. "Plasma NfL concentrations are increased across multiple neurodegenerative disorders but are highest in samples from individuals with ALS, FTD, and DSAD….Furthermore, plasma NfL can differentiate between moderate/severe depression from neurogenerative disorders, which has direct implications for many disorders." So cross your fingers that this test becomes widely available, and don't miss these 7 Ways You're Ruining Your Body After 60, Say Experts.

Alek Korab
Alek Korab is a Co-Founder and Managing Editor of the ETNT Health channel on Eat This, Not That! Read more