A study published in the Journal of the American Medical Association on July 29 now shows that a new blood test may be helpful for detecting Alzheimer’s disease as early as 20 years before the onset of cognitive impairment.
A study published in the Journal of the American Medical Association on July 29 now shows that a new blood test may be helpful for detecting Alzheimer’s disease as early as 20 years before the onset of cognitive impairment.
For years, the diagnosis of Alzheimer’s disease has been based on tau tangles in the brain and amyloid plaques, which are typically not observable until after a patient dies. According to new research, measurements of phospho-tau217 (p-tau217) – one of the tau proteins of the brain – can potentially provide a sensitive, accurate indicator of both plaques and tangles in patients who are still living.
“The p-tau217 blood test has great promise in the diagnosis, early detection and study of Alzheimer’s,” said Oskar Hansson, MD, PhD, Professor of Clinical Memory Research at Lund University, Sweden, who leads the Swedish BioFINDER Study and senior author on the study who spearheaded the international collaborative effort. “While more work is needed to optimize the assay and test it in other people before it becomes available in the clinic, the blood test might become especially useful to improve the recognition, diagnosis, and care of people in the primary care setting.”
To conduct their study, the researchers evaluated a new p-tau217 blood test in 1,402 cognitively impaired and unimpaired subjects from studies in Arizona, Sweden and Colombia. The participants from Arizona were a part of Banner Sun Health Research Institute’s Brain Donation program, and had clinical assessments and blood samples taken in the last years of their life. In addition, they had neurological assessments after they died.
The participants from Sweden were a part of the Swedish BioFINDER Study and had clinical brain imaging, cerebrospinal fluid (CSF) and blood-based biomarker assessments. Finally, the Colombian participants had autosomal dominant Alzheimer’s disease (ADAD)-causing mutation carriers and non-carriers from the world’s largest ADAD cohort.
After analyzing each of these groups, the p-tau217 blood test appeared to perform better than the p-tau181 test.
“Blood tests like p-tau217 have the potential to revolutionize Alzheimer’s research, treatment and prevention trials, and clinical care,” said Eric Reiman, MD, Executive Director of Banner Alzheimer’s Institute in Phoenix and a senior author on the study. “While there’s more work to do, I anticipate that their impact in both the research and clinical setting will become readily apparent within the next two years.”
A drug candidate that has been previously shown to slow aging in brain cells recently demonstrated that it could potentially reverse memory loss in a mouse model. A study published in the July 2020 edition of Redox Biology showed that the drug, CMS121, works by changing how brain cells metabolize lipids in the body.
After three months on CMS121 (at 12 months old), the mice – both treated and untreated – were given a series of memory and behavior tests. All of the mice performed equally well, including those who had an Alzheimer’s-like disease.
“This was a more rigorous test of how well this compound would work in a therapeutic setting than our previous studies on it,” says Pamela Maher, a senior staff scientist in the lab of Salk Professor David Schubert and the senior author of the new paper. “Based on the success of this study, we’re now beginning to pursue clinical trials.”
More than 5 million Americans are living with Alzheimer’s disease, according to the Alzheimer’s Association.
